XRF & XRD Analysis Principle

XRF & XRD Analysis XRF & XRD Analysis PrinciplePrinciple

BY: Muhammad Nohman Mahmud Sr.AM (QC)

Presented to the Quality Control /Assurance staff of Bestway Cement

Group

History of X-rays:History of X-rays:

History of X-Rays :History of X-Rays :• X-rays were discovered in 1895 by the German scientist Wilhelm Conrad Roentgen X-rays were discovered in 1895 by the German scientist Wilhelm Conrad Roentgen

(1845-1923).(1845-1923).• Working with a cathode ray tube (CRT) in a dark room he discovered a white spot on a Working with a cathode ray tube (CRT) in a dark room he discovered a white spot on a photographic film after development. As he did not know what kind of rays came from the photographic film after development. As he did not know what kind of rays came from the

CRT he called those rays X-rays. Later he put his wife’s hand between the CRT and the CRT he called those rays X-rays. Later he put his wife’s hand between the CRT and the photographic plate and after developing the photographic plate he saw the structure of his photographic plate and after developing the photographic plate he saw the structure of his wife’s hand, including finger bones and the wedding ring, on the photographic plate. So wife’s hand, including finger bones and the wedding ring, on the photographic plate. So the application of X-rays for medical diagnostics were apparent from the beginning. For the application of X-rays for medical diagnostics were apparent from the beginning. For his discovery he was awarded the his discovery he was awarded the first Nobel Prize for physics.first Nobel Prize for physics.

• The properties of these X-rays were investigated and by 1912 the principles of diffraction The properties of these X-rays were investigated and by 1912 the principles of diffraction physics and reciprocal space were developed by Rontgen, von Laue, Ewald,Sommerfeld physics and reciprocal space were developed by Rontgen, von Laue, Ewald,Sommerfeld and Brentano in Munich, Germany. It was in 1914 that father and son Bragg (Leeds and and Brentano in Munich, Germany. It was in 1914 that father and son Bragg (Leeds and Manchester, UK) introduced the crystallography. The principles of powder diffractometry Manchester, UK) introduced the crystallography. The principles of powder diffractometry were described in 1916 by Debye and Sheerer (Gottingen, Germany). In that same year were described in 1916 by Debye and Sheerer (Gottingen, Germany). In that same year the structure of LiF was reported. Hull (New Haven, USA) published the structure of -Fe the structure of LiF was reported. Hull (New Haven, USA) published the structure of -Fe in 1917.The first principles of size-strain analysis were published in 1918 by Sherrer.in 1917.The first principles of size-strain analysis were published in 1918 by Sherrer.

DiscovererDiscoverer

History of X-rays:History of X-rays:

• From 1917 to 1919 Brentano developed in Zürich, Switzerland the ideas of the bent From 1917 to 1919 Brentano developed in Zürich, Switzerland the ideas of the bent monochromator and focusing optics, monochromator and focusing optics, but only in 1947 the first commercial but only in 1947 the first commercial powder diffractometer was introduced by Phil ips in the USApowder diffractometer was introduced by Phil ips in the USA , after earlier , after earlier developments of Le Galley (1935), Friedman (1945, Washington, USA) and Parrish and developments of Le Galley (1935), Friedman (1945, Washington, USA) and Parrish and Gordon (1947, USA).The Powder Diffraction File (PDF) from Dow Chemical Company, Gordon (1947, USA).The Powder Diffraction File (PDF) from Dow Chemical Company, started in the late 1930s, was continued from 1950 onwards by the former Joint started in the late 1930s, was continued from 1950 onwards by the former Joint Committee for Powder Diffraction Systems (JCPDS), now called Committee for Powder Diffraction Systems (JCPDS), now called International International Centre for Diffraction Data (ICDD),Centre for Diffraction Data (ICDD), and issued yearly the PDF database on cards and issued yearly the PDF database on cards and in books and later on micro-fiche, tape and now CD-ROM. Starting with a 1000 and in books and later on micro-fiche, tape and now CD-ROM. Starting with a 1000 patterns, that database now contains a number of patterns in the order of magnitude of patterns, that database now contains a number of patterns in the order of magnitude of 100000 and is the most important database in X-ray powder diffraction. The 100000 and is the most important database in X-ray powder diffraction. The development of calculation machines and computers in the 1950s and 1960s brought development of calculation machines and computers in the 1950s and 1960s brought about the full potential of the application of single crystal and powder diffractometry, about the full potential of the application of single crystal and powder diffractometry, which also allowed a great deal of automation. In the 1980s and 1990s new X-ray which also allowed a great deal of automation. In the 1980s and 1990s new X-ray optics, like parallel beam collimators, multi-crystal monochromators, graded mirrors and optics, like parallel beam collimators, multi-crystal monochromators, graded mirrors and capillary lenses were introduced, enabling an even larger range of applications.capillary lenses were introduced, enabling an even larger range of applications.

What are X-rays:What are X-rays:• WHATWHAT AREARE X-RAYS?X-RAYS?• X-rays can be seen as electromagnetic (EM) waves with their associated wavelengths, X-rays can be seen as electromagnetic (EM) waves with their associated wavelengths,

or as beams of photons with associated energies. Both views are correct, but one or the or as beams of photons with associated energies. Both views are correct, but one or the other is easier to understand depending on the phenomena to be explained. Other other is easier to understand depending on the phenomena to be explained. Other electromagnetic wave includes light, radio waves, and gamma rays. The wave lengths electromagnetic wave includes light, radio waves, and gamma rays. The wave lengths of x-rays are in the range from 0.01 to 10nm, which corresponds to energies in the of x-rays are in the range from 0.01 to 10nm, which corresponds to energies in the range from 0.125 to 125 keV. This region is bounded on the short wavelength side by range from 0.125 to 125 keV. This region is bounded on the short wavelength side by Gamma rays and on the long wavelength side by Ultra-Violet radiation. The wave length Gamma rays and on the long wavelength side by Ultra-Violet radiation. The wave length of X-rays is inversely proportional to its energy, according to E*λ= hc, E is the energy in of X-rays is inversely proportional to its energy, according to E*λ= hc, E is the energy in keV and λ the wavelength in nm. The term is the product of Planck’s constant and the keV and λ the wavelength in nm. The term is the product of Planck’s constant and the velocity of light and has, using keV and nm as units, a constant value of 1.23985.The X-velocity of light and has, using keV and nm as units, a constant value of 1.23985.The X-ray wavelength is given in (nm) or, more commonly in the crystallographic world, in the ray wavelength is given in (nm) or, more commonly in the crystallographic world, in the older unit Angstrom (Å).1 Å = 0.1 nm 1 nm = 10 Å older unit Angstrom (Å).1 Å = 0.1 nm 1 nm = 10 Å

What are X-rays:What are X-rays:

X-rays Safety:X-rays Safety:• RADIATIONRADIATION• All kinds of radiation exists in and around us at all times. The question arises what effect All kinds of radiation exists in and around us at all times. The question arises what effect

radiation has on us.radiation has on us.• But first we have to answer the question what is radiation.But first we have to answer the question what is radiation.• Radiation is phenomenon, which can be described as having wave properties, but can Radiation is phenomenon, which can be described as having wave properties, but can

also be described as particles. Some are ionising. also be described as particles. Some are ionising. • For some types of radiation we prefer the wave description, like Electro-magnetic waves For some types of radiation we prefer the wave description, like Electro-magnetic waves

(photons), other radiation is best described as an emission of particles from an atom or (photons), other radiation is best described as an emission of particles from an atom or nucleus, like electrons, protons, neutrons or complete atomic nuclei.nucleus, like electrons, protons, neutrons or complete atomic nuclei.

• A lot of radiation types are harmless, but the more energetic radiation is dangerous A lot of radiation types are harmless, but the more energetic radiation is dangerous because of its ionising nature and other properties, see the next section. because of its ionising nature and other properties, see the next section.

• WARNING X-RAYSWARNING X-RAYS AREARE DANGEROUS!!!DANGEROUS!!!• THEYTHEY CANCAN CAUSECAUSE SERIOUSSERIOUS PERSONALPERSONAL INJURYINJURY IFIF SAFETYSAFETY • INSTRUCTIONSINSTRUCTIONS ANDAND RECOMMENDATIONSRECOMMENDATIONS AREARE NOTNOT FULLYFULLY CARRIEDCARRIED

OUTOUT• PROPERTIESPROPERTIES OFOF SHORTSHORT WAVELENGTHWAVELENGTH ELECTRO-MAGNETICELECTRO-MAGNETIC

RADIATIONRADIATION

X-rays Safety:X-rays Safety:• The following properties make short wavelength (high-energy) Electro-magnetic The following properties make short wavelength (high-energy) Electro-magnetic

radiation a dangerous phenomenon:radiation a dangerous phenomenon:• _ They are not physically detectable by the human senses like smell, taste, touch or _ They are not physically detectable by the human senses like smell, taste, touch or

visionvision• _ They are always transmitted in a straight line_ They are always transmitted in a straight line• _ They travel at the speed of light_ They travel at the speed of light• _ There is almost no refraction by means of normal lenses or prisms_ There is almost no refraction by means of normal lenses or prisms• _ They penetrate in and through matter_ They penetrate in and through matter• _ They are ionising (generate charged particles)_ They are ionising (generate charged particles)• _ They destroy and damage human tissue (burning, damage of the cell genetic material, _ They destroy and damage human tissue (burning, damage of the cell genetic material,

which can cause cancer) which can cause cancer) • RADIATIONRADIATION DOSEDOSE• Since it is known that radiation can be dangerous people have been searching for Since it is known that radiation can be dangerous people have been searching for

criteria, which describe an amount of radiation that is still safe or has to be considered criteria, which describe an amount of radiation that is still safe or has to be considered dangerous. For this the general term dose is used. The following terms and units have dangerous. For this the general term dose is used. The following terms and units have been or are still used for this:been or are still used for this:

X-rays Safety:X-rays Safety:• _ _ ActivityActivity• This only describes the activity of radioactive material, being the number of atom changes This only describes the activity of radioactive material, being the number of atom changes

(emissions) per unit of time.(emissions) per unit of time.• The unit in which the activity is expressed is Becquerel per second or Bq/s. The old unit is The unit in which the activity is expressed is Becquerel per second or Bq/s. The old unit is

the Curie or Ci (1 Ci=3.7·1010 Bq/s).the Curie or Ci (1 Ci=3.7·1010 Bq/s).• _ _ ExposureExposure• Exposure is the quantity of released charge per kilogram of air.Exposure is the quantity of released charge per kilogram of air.• The unit in which exposure is expressed is Coulomb per kilogram air or C/kg.The unit in which exposure is expressed is Coulomb per kilogram air or C/kg.• The old unit is the Roentgen or R. (1 R=2.58·10-4 C/kg).The old unit is the Roentgen or R. (1 R=2.58·10-4 C/kg).• _ _ AbsorbedAbsorbed dosedose• The absorbed dose is the absorbed energy per kilogram of material. The unit in which The absorbed dose is the absorbed energy per kilogram of material. The unit in which

absorbed dose is expressed is Gray or Gy (1 Gy =1 J/kg).The old unit is the Radiation absorbed dose is expressed is Gray or Gy (1 Gy =1 J/kg).The old unit is the Radiation absorbed dose or Rad (1 Rad=0.01 Gy). absorbed dose or Rad (1 Rad=0.01 Gy).

• -Dose-Dose equivalentequivalent• The dose equivalent is the absorbed dose multiplied by a quality factor.This quality factor is The dose equivalent is the absorbed dose multiplied by a quality factor.This quality factor is

depending on the type of radiation and its relative damaging potential:depending on the type of radiation and its relative damaging potential:• The unit in which dose equivalent is expressed is the Sievert or Sv (1 Sv =1 Gy=1 J/kg).The unit in which dose equivalent is expressed is the Sievert or Sv (1 Sv =1 Gy=1 J/kg).• The old unit is the Röntgen Equivalent Men or REM The old unit is the Röntgen Equivalent Men or REM • (1 REM=0.01 Sv).(1 REM=0.01 Sv).

X-rays Safety:X-rays Safety:• EFFECTSEFFECTS ONON THETHE HUMANHUMAN BODYBODY• The overall effects on the human body depending on the total dose received are of course The overall effects on the human body depending on the total dose received are of course

very important. The following table gives an overview of the effects and chance of survival very important. The following table gives an overview of the effects and chance of survival after an exposure to a radiation source.after an exposure to a radiation source.

• TotalTotal bodybody exposure Effectexposure Effect onon humanhuman body Chancesbody Chances ofof survivalsurvival

• 100 Sv Damage to central nerve system No chance/Only few hours100 Sv Damage to central nerve system No chance/Only few hours• 10 Sv Damage to stomach, guts, bone marrow Little, <50%10 Sv Damage to stomach, guts, bone marrow Little, <50%• 1 Sv Change in blood composition Reasonable, >50%1 Sv Change in blood composition Reasonable, >50%• 0.1 Sv no physical damage Complete recovery after about 6 weeks0.1 Sv no physical damage Complete recovery after about 6 weeks

X-rays Legislation:X-rays Legislation:• LEGISLATIONLEGISLATION• Country OfficialCountry Official DocumentsDocuments ContainingContaining RegulationsRegulations• GermanyGermany Verordnung über den Schutz vor Schaden durch Röntgenstrahlen Verordnung über den Schutz vor Schaden durch Röntgenstrahlen• UKUK The Ionising Radiation Regulation, 1985, United Kingdom The Ionising Radiation Regulation, 1985, United Kingdom• USA USA Radiation Safety for X-ray Diffraction and Fluorescence Analysis Equipment, (NBS Radiation Safety for X-ray Diffraction and Fluorescence Analysis Equipment, (NBS

hand book 1977)Department of Health Education and Welfare (DHEW), FDA 75 8003hand book 1977)Department of Health Education and Welfare (DHEW), FDA 75 8003• CanadaCanada Radiation Emitting Devices Act, SOR/DORS/81-545, Radiation Emitting Devices Act, SOR/DORS/81-545,• Part XVIII: Cabinet of X-ray Equipment Consultative Document,Part XVIII: Cabinet of X-ray Equipment Consultative Document,• Part XIV: X-ray Diffraction EquipmentPart XIV: X-ray Diffraction Equipment• Austral ia Austral ia Code of Practice for Protection against Ionising Radiation Emitted Code of Practice for Protection against Ionising Radiation Emitted • from X-ray Analysis Equipment, (1984)from X-ray Analysis Equipment, (1984)• The approach of Philips is to take care of the user (customer) and provide equipment that The approach of Philips is to take care of the user (customer) and provide equipment that

is better than the lowest permissible dose limit. These dose limits are described in the is better than the lowest permissible dose limit. These dose limits are described in the legislation of the USA and the Netherlands and is currently 2.5 micro Sv/hour.legislation of the USA and the Netherlands and is currently 2.5 micro Sv/hour.

Theory of XRF:Theory of XRF:• Theory of XRF:Theory of XRF:• In XRF X-rays produced by a source irradiate a sample. In most case the source is an X-In XRF X-rays produced by a source irradiate a sample. In most case the source is an X-

ray tube. The element present in the sample will emit the fluorescent x-ray radiation with ray tube. The element present in the sample will emit the fluorescent x-ray radiation with discrete energies equivalent to color for optical light that are characteristics for these discrete energies equivalent to color for optical light that are characteristics for these elements. A different energy is equivalent to a different color. By measuring the energies elements. A different energy is equivalent to a different color. By measuring the energies determining the color of the radiation emitted by the sample it is possible to determine determining the color of the radiation emitted by the sample it is possible to determine which elements are present this step is called qualitative analysis. By measuring the which elements are present this step is called qualitative analysis. By measuring the intensities of the emitted energies (colors) it is possible to determine how much of each intensities of the emitted energies (colors) it is possible to determine how much of each element is present in the sample. This step is called quantitative analysis.element is present in the sample. This step is called quantitative analysis.

• Interaction of X-rays with matter:Interaction of X-rays with matter:• There are three main interactions of x-rays with matter: There are three main interactions of x-rays with matter: Fluorescence, Compton Fluorescence, Compton

scatter and Rayleigh scatterscatter and Rayleigh scatter . If X-ray fall on a material a fraction will pass . If X-ray fall on a material a fraction will pass through the sample, a fraction is absorbed into the sample and produce fluorescent through the sample, a fraction is absorbed into the sample and produce fluorescent radiation, and a fraction is scattered back. Scattering can occur with loss of energy and radiation, and a fraction is scattered back. Scattering can occur with loss of energy and with out loss of energy. The first is called with out loss of energy. The first is called Compton scatter Compton scatter and the second and the second RayleighRayleigh scatterscatter . The fluorescence and scatter depends upon the thickness (d) and density (ρ) . The fluorescence and scatter depends upon the thickness (d) and density (ρ) and composition of the material and on the energy of the X-rays. and composition of the material and on the energy of the X-rays.

Theory of XRF:Theory of XRF:• Production of Characterist ic f luorescent radiation:Production of Characterist ic f luorescent radiation:• The classical model of an atom is a nucleus with positively charged protons and non-The classical model of an atom is a nucleus with positively charged protons and non-

charged neutrons, surrounded by electrons grouped in shells or orbitals. The innermost charged neutrons, surrounded by electrons grouped in shells or orbitals. The innermost shell is called the K-shell, followed by l-shells, M-shells etc travelling outwards. The L-shell shell is called the K-shell, followed by l-shells, M-shells etc travelling outwards. The L-shell has 3 sub shells called L1, L11 and LIII. The M shell has 5 sub shells. The K shell can has 3 sub shells called L1, L11 and LIII. The M shell has 5 sub shells. The K shell can contain 2 electrons, the L-shell 8 and the M-shell 18. The energy an electron has depends contain 2 electrons, the L-shell 8 and the M-shell 18. The energy an electron has depends on the shell it is in, and on the element to which it belongs. Irradiating an atom, particles like on the shell it is in, and on the element to which it belongs. Irradiating an atom, particles like X-ray photons and electrons with sufficient energy can expel an electron from the atom.X-ray photons and electrons with sufficient energy can expel an electron from the atom.

• This produces a hole in a shell, in the example a hole in the K-shell, putting the atom in an This produces a hole in a shell, in the example a hole in the K-shell, putting the atom in an unstable situation with a higher energy. The atom wants to restore the original unstable situation with a higher energy. The atom wants to restore the original configuration, and this is done by transferring an electron from an outer shell e.g. the l-shell configuration, and this is done by transferring an electron from an outer shell e.g. the l-shell to the hole in the K-shell. An L-shell electron has a higher energy than a K-shell electron to the hole in the K-shell. An L-shell electron has a higher energy than a K-shell electron and when the L-shell electron is transferred to the K-shell, the energy surplus is emitted as and when the L-shell electron is transferred to the K-shell, the energy surplus is emitted as X-rays. In a spectrum, this is seen as a line. The energy of the emitted X-rays depends on X-rays. In a spectrum, this is seen as a line. The energy of the emitted X-rays depends on the difference in energy of the shell with the initial hole and the energy of the electron that the difference in energy of the shell with the initial hole and the energy of the electron that fills the hole. Each atom has its specific energy levels, so the emitted radiation is fills the hole. Each atom has its specific energy levels, so the emitted radiation is characteristic for that atom. An atom emits more than just one energy (or line), because characteristic for that atom. An atom emits more than just one energy (or line), because different holes can be produced and different electrons can fill up these holes. The different holes can be produced and different electrons can fill up these holes. The collection of emitted lines is characteristic for the element and is more or less a fingerprint collection of emitted lines is characteristic for the element and is more or less a fingerprint of the element.of the element.

Theory of XRF:Theory of XRF:• To expel an electron from an atom, the x-rays must have a higher energy than the binding To expel an electron from an atom, the x-rays must have a higher energy than the binding

energy of the electron. If an electron is expelled, the incoming radiation is absorbed and the energy of the electron. If an electron is expelled, the incoming radiation is absorbed and the higher the absorption the higher the fluorescence. If on the other hand the energy is too higher the absorption the higher the fluorescence. If on the other hand the energy is too high, many photons will pass the atom and only a few electrons will be removed. If the high, many photons will pass the atom and only a few electrons will be removed. If the energy is lower and comes closer to the binding energy of the K-shell electrons, more and energy is lower and comes closer to the binding energy of the K-shell electrons, more and more radiation is absorbed. The highest yield is reached when the energy of the photon is more radiation is absorbed. The highest yield is reached when the energy of the photon is just above the binding energy of the electron to be expelled. If the energy becomes lower just above the binding energy of the electron to be expelled. If the energy becomes lower than the binding energy, a jump or edge can be seen: the energy is too low to expel than the binding energy, a jump or edge can be seen: the energy is too low to expel electrons from that shell, but is too high to expel electrons from the lower energetic shells. electrons from that shell, but is too high to expel electrons from the lower energetic shells.

• Not all incoming photons produce fluorescent photons. The fluorescence yield is the ratio of Not all incoming photons produce fluorescent photons. The fluorescence yield is the ratio of the emitted fluorescent photons and the number of incoming photons. the yield is low for the emitted fluorescent photons and the number of incoming photons. the yield is low for the very light elements, explaining why it is so difficult to measure these elementsthe very light elements, explaining why it is so difficult to measure these elements..

Types of XRF’s:Types of XRF’s:Types of Spectrometer Systems:Types of Spectrometer Systems:There are two types of XRF Systems ,Energy Dispersive XRF & Wave length There are two types of XRF Systems ,Energy Dispersive XRF & Wave length

Dispersive XRFDispersive XRFEDXRF :EDXRF :• EDXRF Spectrometer have a detector that is able to measure the different energies of EDXRF Spectrometer have a detector that is able to measure the different energies of

the characteristics' radiation coming directly from the sample.The detector can separate the characteristics' radiation coming directly from the sample.The detector can separate the radiation from the sample into the radiation from the elements in the sample.the radiation from the sample into the radiation from the elements in the sample.

• WDXRD:WDXRD:• WDXRF Spectrometer use an analyzing crystal to disperse the different energies. All WDXRF Spectrometer use an analyzing crystal to disperse the different energies. All

radiation coming from the sample fall on the crystal. The crystal diffracts the different radiation coming from the sample fall on the crystal. The crystal diffracts the different energies into different radiations ,similar to a prism that disperses colors into different energies into different radiations ,similar to a prism that disperses colors into different directions.directions.

Is also possible to mount the detector on a goniometer and move it through an angular range Is also possible to mount the detector on a goniometer and move it through an angular range to measure the intensities of many different wave lengths. This system is called as to measure the intensities of many different wave lengths. This system is called as sequential systems because they measure the intensities of the different wavelengths sequential systems because they measure the intensities of the different wavelengths one After another. Simultaneous spectrometers are equipped with a set of fixed detection one After another. Simultaneous spectrometers are equipped with a set of fixed detection system. Each detection system has its crystal and detector ,and each system measures system. Each detection system has its crystal and detector ,and each system measures the radiation of a specific element .the intensities are measured all at the same the radiation of a specific element .the intensities are measured all at the same time,explaning why they are termed as simultaneous systems. combined systems having time,explaning why they are termed as simultaneous systems. combined systems having an moving detector and fixed detectors are also available.an moving detector and fixed detectors are also available.

Instrumentation:Instrumentation:• As XRF Present in BCL CHK is WDXRF ,therefore we wil l focus on WDXRF:As XRF Present in BCL CHK is WDXRF ,therefore we wil l focus on WDXRF:• Cubix 2300 XRF :Cubix 2300 XRF :• The spectrometer comprises the following major assemblies.The spectrometer comprises the following major assemblies.• Analyzer Containing:Analyzer Containing:• Measuring ChamberMeasuring Chamber• Element Channels & detectorsElement Channels & detectors• Sample Transport AssembleySample Transport Assembley• Vacumn PumpVacumn Pump• TT X-Ray Tube:TT X-Ray Tube:• Controller Containing:Controller Containing:• HT SupplyHT Supply• Internal Water Cooling SystemInternal Water Cooling System• CPU BoardCPU Board• Controller BoardController Board• Counting ElectronicsCounting Electronics

Instrumentation :Instrumentation :• Measuring Chamber :Measuring Chamber :• Measuring chamber is located in the analyzer.It consists of the measuring chamber itself Measuring chamber is located in the analyzer.It consists of the measuring chamber itself

and 14 fixed measuring channels ,or optionally with a maximum of 11 fixed channels.and 14 fixed measuring channels ,or optionally with a maximum of 11 fixed channels. • Element Channel :Element Channel :• A fixed element channel comprises the following ,A fixed element channel comprises the following ,• Entrance Slit Entrance Slit • DiaphragmDiaphragm• Curved Crystal AssembleyCurved Crystal Assembley• Exit slitExit slit• DetectorDetector• Scaler Circuit Scaler Circuit • Connecting CablesConnecting Cables• Each channel has a high tension supply for the detector and when a gas flow detector is Each channel has a high tension supply for the detector and when a gas flow detector is

used ,a controlled gas supply.used ,a controlled gas supply.

Instrumentation :Instrumentation :• Detector & Mult i Channel Analyzer :Detector & Mult i Channel Analyzer :• EDXRF mainly use solid state detector ,while WDXRF use gas filled detectors and EDXRF mainly use solid state detector ,while WDXRF use gas filled detectors and

scintillation detectors.EDXRF detector is a wide range detector and measures all scintillation detectors.EDXRF detector is a wide range detector and measures all elements from Na up to U.Gas filled detectors measures elements from Be upto Cu and elements from Na up to U.Gas filled detectors measures elements from Be upto Cu and scintilllation detector from Cu upto U.All these detectors' produce an electrical pulse scintilllation detector from Cu upto U.All these detectors' produce an electrical pulse when an X-Ray photon enters the detector ,and height of this pulse is proportional to the when an X-Ray photon enters the detector ,and height of this pulse is proportional to the energy of the incoming photon. The pulses are amplified and than counted by Multi energy of the incoming photon. The pulses are amplified and than counted by Multi Channel analyzer. Channel analyzer.

• There are 03 important parameters of detection system:There are 03 important parameters of detection system:• Resolution :Resolution :• Is the ability of the detector to distinguish between different energy levels. A high Is the ability of the detector to distinguish between different energy levels. A high

resolution means the detector can distinguish between different energies level.resolution means the detector can distinguish between different energies level.• Sensitivity :Sensitivity :• Indicates how efficiently incoming photons are counted. Sensitivity is high if the ratio of Indicates how efficiently incoming photons are counted. Sensitivity is high if the ratio of

number of pulses against the number of incoming photons is high.number of pulses against the number of incoming photons is high.• Dispersion :Dispersion :• Indicates the ability of the detector to separate X-rays with different energies. high Indicates the ability of the detector to separate X-rays with different energies. high

dispersion means different energies are separated well.dispersion means different energies are separated well.• As in our XRF System there is gas filled detector system, therefore well focus on them :As in our XRF System there is gas filled detector system, therefore well focus on them :

Instrumentation :Instrumentation :• Gas Fi l led Detector System:Gas Fi l led Detector System:• The sealed gas detector is a hollow metal cylinder with an anode wire running in the axial The sealed gas detector is a hollow metal cylinder with an anode wire running in the axial

centre of the cylinder. The cylinder is sealed of and has a gas mixture inside, containing centre of the cylinder. The cylinder is sealed of and has a gas mixture inside, containing the inert counting gas (Ne,Ar,Kr ,Xe and occasionally He) and the quench gas Methane. the inert counting gas (Ne,Ar,Kr ,Xe and occasionally He) and the quench gas Methane. On one side of the cylinder a Be window is mounted through which the X-ray photons can On one side of the cylinder a Be window is mounted through which the X-ray photons can enter. When an X-ray photon enters the detector and collides with an inert gas atom an enter. When an X-ray photon enters the detector and collides with an inert gas atom an outer electron may be knocked out forming an ion-electron pair. The number of ion-outer electron may be knocked out forming an ion-electron pair. The number of ion-electron pairs is depending on the energy of the X-ray photon. The electrons from the electron pairs is depending on the energy of the X-ray photon. The electrons from the ion-electron pair are then accelerated towards the anode wire by its high potential. In its ion-electron pair are then accelerated towards the anode wire by its high potential. In its path such an accelerating electron can again knock out an electron from an atom, path such an accelerating electron can again knock out an electron from an atom, forming another ion-electron pair etc.This will cause an avalanche of electrons, the so-forming another ion-electron pair etc.This will cause an avalanche of electrons, the so-called gas amplification. When this avalanche of electrons reaches the anode wire, a called gas amplification. When this avalanche of electrons reaches the anode wire, a small voltage pulse is produced. This voltage pulse is proportional to the energy of the X-small voltage pulse is produced. This voltage pulse is proportional to the energy of the X-ray photon and the applied HT.If negative ions are produced also positive ions are ray photon and the applied HT.If negative ions are produced also positive ions are produced. These positive ions are attracted to the detector case at earth potential and produced. These positive ions are attracted to the detector case at earth potential and they will also cause an avalanche. To prevent this, the inert gas is mixed with a quench they will also cause an avalanche. To prevent this, the inert gas is mixed with a quench gas, such as Methane. The quench gas has the effect of neutralizing the positive ions gas, such as Methane. The quench gas has the effect of neutralizing the positive ions without any other reactions.without any other reactions.

Instrumentation :Instrumentation :• Gas Flow Proportional Detector:Gas Flow Proportional Detector:• It is used for X-Rays having energies between 0.28 KeV & 3 KeV.It is operated with a It is used for X-Rays having energies between 0.28 KeV & 3 KeV.It is operated with a

continuous flow of gas .P10 Gas is used 90 % Argon & 10 % Methane .The gas flow continuous flow of gas .P10 Gas is used 90 % Argon & 10 % Methane .The gas flow must be between 0.5 & 1 LITRE / HOUR.must be between 0.5 & 1 LITRE / HOUR.

• The recommended use is for lighter elements from C to Mg.It is also possible to use this The recommended use is for lighter elements from C to Mg.It is also possible to use this detector for Al to Cr.detector for Al to Cr.

• Neon Sealed Proportional Detector :Neon Sealed Proportional Detector :• It is used for X-Rays having energies between 1.5 KeV & 3 KeV.The detector is filled & It is used for X-Rays having energies between 1.5 KeV & 3 KeV.The detector is filled &

sealed with Neon gas mixture.sealed with Neon gas mixture.• The Neon sealed detector fitted with 25 Um window can be used to analyze elements The Neon sealed detector fitted with 25 Um window can be used to analyze elements

from Al upto P.A detector with a 50 um window is used to analyze elements from S upto from Al upto P.A detector with a 50 um window is used to analyze elements from S upto Cl.Cl.

• Krypton Sealed Proportional Detector :Krypton Sealed Proportional Detector :• It is used for X-Rays having energies between 3 KeV & 8 KeV.The detector is filled & It is used for X-Rays having energies between 3 KeV & 8 KeV.The detector is filled &

sealed with Krypton gas mixture.sealed with Krypton gas mixture.• The Krypton sealed detector can be used to analyze elements from K upto Cu (K Line).A The Krypton sealed detector can be used to analyze elements from K upto Cu (K Line).A

& for the L-Line analysis of elements from Te to Ta.& for the L-Line analysis of elements from Te to Ta.

Instrumentation :Instrumentation :• Xenon Sealed Proportional Detector :Xenon Sealed Proportional Detector :• It is used for X-Rays having energies between 6 KeV & 16 KeV.The detector is filled & It is used for X-Rays having energies between 6 KeV & 16 KeV.The detector is filled &

sealed with Xenon gas mixture.sealed with Xenon gas mixture.• The Xenon sealed detector can be used to analyze elements from Zn upto Y (K Line). & The Xenon sealed detector can be used to analyze elements from Zn upto Y (K Line). &

for the L-Line analysis of elements from Ta to U.for the L-Line analysis of elements from Ta to U.• COMPARISON OF DIFFERENT DECTECTORS COMPARISON OF DIFFERENT DECTECTORS • The resolution of gas filled and scintillation detectors are very poor, and they are not The resolution of gas filled and scintillation detectors are very poor, and they are not

suited for energy dispersive spectrometers. They can however be used in wavelength suited for energy dispersive spectrometers. They can however be used in wavelength dispersive spectrometers, because in these instruments the resolution is achieved by the dispersive spectrometers, because in these instruments the resolution is achieved by the diffraction crystal. The sensitivity depends on the type of detector and on the energy of diffraction crystal. The sensitivity depends on the type of detector and on the energy of the incoming X- rays. Gas –filled detectors have a high sensitivity for low energy and a the incoming X- rays. Gas –filled detectors have a high sensitivity for low energy and a low sensitivity for high energies and are so best suited to detect low energies. The low sensitivity for high energies and are so best suited to detect low energies. The opposite applies for scintillation detectors ,which are better suited for high energies than opposite applies for scintillation detectors ,which are better suited for high energies than low energies .Solid state detectors in general have a very low sensitivity for low energies low energies .Solid state detectors in general have a very low sensitivity for low energies and high resolution for the higher energies.EDXRF Spectrometer commonly use solid and high resolution for the higher energies.EDXRF Spectrometer commonly use solid state detector ,while WDXRF spectrometers use a combination of gas filled and state detector ,while WDXRF spectrometers use a combination of gas filled and scintillation detector.scintillation detector.

Instrumentation :Instrumentation :

• Lif 220 Crystal 2d = 0.2848 nm: used for elemental range V-U, high Lif 220 Crystal 2d = 0.2848 nm: used for elemental range V-U, high resolution analysis resolution analysis

• LiF200 Crystal :2d=0.4027 nm : used for elemental K-U ,routine analysis. LiF200 Crystal :2d=0.4027 nm : used for elemental K-U ,routine analysis. • Insb (111) Crystal 2d= 0.7477 : this is only used for si l icon and gives a Insb (111) Crystal 2d= 0.7477 : this is only used for si l icon and gives a

higher sensit ivity than PE with also an improved resolutionhigher sensit ivity than PE with also an improved resolution• PE (002) Crystal 2d=0.8742 nm : Elemental range Al-Cl. Routine analysisPE (002) Crystal 2d=0.8742 nm : Elemental range Al-Cl. Routine analysis• PX1 Synthetic Mult i layer 2d = 5 nm: Analysis range O-MgPX1 Synthetic Mult i layer 2d = 5 nm: Analysis range O-Mg• PX4 Synthetic Mult i layer : 2d = 12nm used for analysis of carbon.PX4 Synthetic Mult i layer : 2d = 12nm used for analysis of carbon.

• Counting & Control Electronics :Counting & Control Electronics :• The Dual scaler board is used to count the detected pulses. This data is passed to the The Dual scaler board is used to count the detected pulses. This data is passed to the

SuperQ analytical software as raw count rate. The Dual scaler board also sets the SuperQ analytical software as raw count rate. The Dual scaler board also sets the detector high voltage level detector high voltage level ..

Instrumentation :Instrumentation :• Detector High Voltage Supplies :Detector High Voltage Supplies :• A high voltage supply is required for each type of detector.A high voltage supply is required for each type of detector.• A gas -flow or sealed detector is supplied with between 1000 to 3000 volts.A gas -flow or sealed detector is supplied with between 1000 to 3000 volts.• The detector high voltage supply is controlled by the Dual Scaler Board.The detector high voltage supply is controlled by the Dual Scaler Board.• Chamber Atmosphere:Chamber Atmosphere:• The inside of the chamber is kept under vacuum ,the vacuum ensures the highest The inside of the chamber is kept under vacuum ,the vacuum ensures the highest

possible intensity for light elements. Whole of the sample transport system and the possible intensity for light elements. Whole of the sample transport system and the measuring chamber is under vacuum.measuring chamber is under vacuum.

• HV Generator :HV Generator :• The high voltage supply is basical ly a 200 Watt high voltage converter with The high voltage supply is basical ly a 200 Watt high voltage converter with

negative polarity.negative polarity.• Routine X Rays Check :Routine X Rays Check :• Cleaning the Loading OpeningCleaning the Loading Opening• Cleaning the air dust FilterCleaning the air dust Filter• Vacumn Pump Oil level CheckVacumn Pump Oil level Check• Vacumn Pump Oil Condit ions CheckVacumn Pump Oil Condit ions Check• Fore l ine Trap CheckFore l ine Trap Check

Instrumentation :Instrumentation :• X-Rays Tubes:X-Rays Tubes:• The basic design of X-Ray Tube contains a filament (wire) and an anode (target) placed The basic design of X-Ray Tube contains a filament (wire) and an anode (target) placed

in an vacuum housing. An electrical current heats up the filament and electrons are in an vacuum housing. An electrical current heats up the filament and electrons are emitted, which hit the atoms in the anode which will expel the electrons from theses emitted, which hit the atoms in the anode which will expel the electrons from theses atoms, causing emission of characteristics radiation. The energy of this radiation is atoms, causing emission of characteristics radiation. The energy of this radiation is determined by the elements in the anode. The X-Rays emitted escape through Be determined by the elements in the anode. The X-Rays emitted escape through Be Window .There are two types of X-Ray Tube Side-Window tubes & Target transmission Window .There are two types of X-Ray Tube Side-Window tubes & Target transmission Tubes .A high voltage (20….100Kv ) is applied across the filamentTubes .A high voltage (20….100Kv ) is applied across the filament t and the anode ,and t and the anode ,and this high voltage accelerates the electrons towards the anode.this high voltage accelerates the electrons towards the anode.

• The conversion of electrons into X-rays is a very inefficient process. About 1% of the The conversion of electrons into X-rays is a very inefficient process. About 1% of the applied energy is converted to X-rays. The remainder of the energy is converted to heat applied energy is converted to X-rays. The remainder of the energy is converted to heat within the anode. Therefore, the backside of the anode is cooled with a high-speed within the anode. Therefore, the backside of the anode is cooled with a high-speed water jet of about 4 litres/ minute. A number of electrons are scattered from the anode water jet of about 4 litres/ minute. A number of electrons are scattered from the anode and strike other parts of the tube such as the window.and strike other parts of the tube such as the window.

• Therefore, the temperature of the window can rise to hundreds of degrees C.Therefore, the temperature of the window can rise to hundreds of degrees C.• The window is made of Beryllium (atomic weight 4) in order to minimize the absorption The window is made of Beryllium (atomic weight 4) in order to minimize the absorption

of X-rays. The thickness of the window depends on the ability to conduct heat from the of X-rays. The thickness of the window depends on the ability to conduct heat from the window to the tube body to avoid fracture of the windowwindow to the tube body to avoid fracture of the window

•

InstrumentationInstrumentation

Channels SpecificationsChannels Specifications

Element Crystal Type AngleSi Insb111 Flow 144.75Al PE002 Flow 144.86Fe LiF200 Sealed Kr 57.52Ca LiF200 Sealed Kr 113.08Mg PX1 Flow 22.56K LiF200 Sealed Kr 136.69Na PX1 Flow 27.48S Ge111 Sealed Ne 110.68Cl PE002 Sealed Ne 65.49

Equipment Details:Equipment Details:

Max MinGas Flow 3.0 l /

hrs,1300 hpa0.5 l/hrs ,600 hpa

X-Ray Tube 50 kv,4 ma Cr 200 WVacumn 100 pa 0 paTemp 36.40 C 35.90 CCompressed Air

6 Bar 4 Bar

Standardization of XRF:Standardization of XRF:

• STANDARDIZATION OF XRF ANALYSISSTANDARDIZATION OF XRF ANALYSIS

• Several standards are available to monitor quality assurance and certification of XRF Several standards are available to monitor quality assurance and certification of XRF equipment performance and accuracy. A brief description of select materials is given equipment performance and accuracy. A brief description of select materials is given below:below:

• Standard Reference MaterialsStandard Reference Materials• A number of Certified Reference Materials (CRMs) and Reference Materials (RMs) A number of Certified Reference Materials (CRMs) and Reference Materials (RMs)

are available from many sources. The definitions for CRM and RM as listed in the are available from many sources. The definitions for CRM and RM as listed in the International Organization for Standardization's ISO Guide 30:1992, “Terms and International Organization for Standardization's ISO Guide 30:1992, “Terms and Definitions Used in Connection with Reference Materials,” are listed below.Definitions Used in Connection with Reference Materials,” are listed below.

• Certif ied Reference Material (CRM). Certif ied Reference Material (CRM). Reference material, accompanied by a Reference material, accompanied by a certificate, one or more of whose property values are certified by a procedure which certificate, one or more of whose property values are certified by a procedure which establishes its traceability to an accurate realization of the unit in which the property establishes its traceability to an accurate realization of the unit in which the property values are expressed, and for which each certified value is accompanied by an values are expressed, and for which each certified value is accompanied by an uncertainty at a stated level of confidence. CRMs are certified by a recognized uncertainty at a stated level of confidence. CRMs are certified by a recognized certifying organization using approved certification procedures as instructed incertifying organization using approved certification procedures as instructed in


• ISO Guide 35:1989, “Certification of Reference Materials – General and Statistical ISO Guide 35:1989, “Certification of Reference Materials – General and Statistical Principles.” The organization is usually a function of a federal government or Principles.” The organization is usually a function of a federal government or recognized by a federal government .A CRM is the highest level to which an recognized by a federal government .A CRM is the highest level to which an analytical reference material can be elevated.analytical reference material can be elevated.

• Reference Material (RM): Reference Material (RM): A material substance one or more of whose property A material substance one or more of whose property values are sufficiently homogeneous and well established to be used for the values are sufficiently homogeneous and well established to be used for the calibration of an apparatus, the assessment of a measurement method, or assigning calibration of an apparatus, the assessment of a measurement method, or assigning values to materials. The RMs usually have been through inter laboratory testing using values to materials. The RMs usually have been through inter laboratory testing using many analysts and supplied with a certificate of analysis but do not strictly follow the many analysts and supplied with a certificate of analysis but do not strictly follow the procedures of certification as indicated in ISO Guide 35:1989.procedures of certification as indicated in ISO Guide 35:1989.

• It is interesting to note that no cement raw mix standards exist – and for good reason. It is interesting to note that no cement raw mix standards exist – and for good reason. Mineralogy of the kiln feed is variable at different cement plants; some use clay and Mineralogy of the kiln feed is variable at different cement plants; some use clay and limestone and others contain quartz, fly ash, bottom ash, and many other materials. limestone and others contain quartz, fly ash, bottom ash, and many other materials. Significantly different results may result depending on the ingredients when using Significantly different results may result depending on the ingredients when using pressed powders in analyses. However, if the fusion technique is used, cement pressed powders in analyses. However, if the fusion technique is used, cement calibrations can be used effectively to analyze raw feed andcalibrations can be used effectively to analyze raw feed and

Standardization of XRF :Standardization of XRF :

• clinker as well. Careful attention to sulfur, alkalis , and chloride is still required. Cement clinker as well. Careful attention to sulfur, alkalis , and chloride is still required. Cement standards, available from NIST, vary in composition so they can be used in calibration standards, available from NIST, vary in composition so they can be used in calibration or qualification under ASTM C 114.3. Supplies usually last 15 years or more as or qualification under ASTM C 114.3. Supplies usually last 15 years or more as thousands of samples are packaged and randomly tested for homogeneity and thousands of samples are packaged and randomly tested for homogeneity and composition to produce a Certificate of Analysis (COA).composition to produce a Certificate of Analysis (COA). Other reference material Other reference material suppliers have one or two standards, which will add to the number of samples used for suppliers have one or two standards, which will add to the number of samples used for calibration, or can supplement the qualification of the test methods. Because the calibration, or can supplement the qualification of the test methods. Because the Cement and Concrete Reference Laboratory (CCRL) samples are analyzed by 100 Cement and Concrete Reference Laboratory (CCRL) samples are analyzed by 100 laboratories or more and statistically evaluated, it is not uncommon for these samples to laboratories or more and statistically evaluated, it is not uncommon for these samples to be used as standards in calibration work. Caution is warranted in this practice because be used as standards in calibration work. Caution is warranted in this practice because the results are averages of many labs’ results, not “certificate values.” Nettles (1998) the results are averages of many labs’ results, not “certificate values.” Nettles (1998) proposed using pure compounds formulated to mimic the composition of the 1800 proposed using pure compounds formulated to mimic the composition of the 1800 series cements using the fusion technique. Other sources of reference materials can be series cements using the fusion technique. Other sources of reference materials can be found in Appendix E.found in Appendix E.

• Drift standards. Drift standards. Drift standards correct for any instrumental changes such as x-ray Drift standards correct for any instrumental changes such as x-ray tube agingtube aging, , detector sensitivity, etc. Such drift standards should be stable materials free detector sensitivity, etc. Such drift standards should be stable materials free from changes due to exposure to x-rays and aging. Typically, driftfrom changes due to exposure to x-rays and aging. Typically, drift


standards are fused beads for cement. Currently available are glass standards made by A.S.O. standards are fused beads for cement. Currently available are glass standards made by A.S.O. Design specifically formulated for Portland cement manufacture concentration ranges. Breitlander Design specifically formulated for Portland cement manufacture concentration ranges. Breitlander also supplies glass drift standards. In any case, the drift correction must be used if chemical also supplies glass drift standards. In any case, the drift correction must be used if chemical results indicate substantial evidence that the method is not providing results in accordance with results indicate substantial evidence that the method is not providing results in accordance with ASTM permissible limits. ASTM permissible limits. If the required accuracy on a major element is 0.1% relative and the If the required accuracy on a major element is 0.1% relative and the measured count rate fluctuates between -0.4% and +0.4% during a period of one week, then one measured count rate fluctuates between -0.4% and +0.4% during a period of one week, then one measurement a day is likely to be sufficient to obtain the required accuracy.measurement a day is likely to be sufficient to obtain the required accuracy.

• The PHD The PHD is the energy distribution of the pulses produced by a detector. The detector count is the energy distribution of the pulses produced by a detector. The detector count rates are displayed as a function of energy using the Check PHD function. Only those signals rates are displayed as a function of energy using the Check PHD function. Only those signals which originate from the element of interest need to be processed from all the signals which are which originate from the element of interest need to be processed from all the signals which are detected. To define the appropriate signals, you must measure a pulse height distribution and set detected. To define the appropriate signals, you must measure a pulse height distribution and set the the upper and lower levels upper and lower levels between which the signal will be integrated for further processing. between which the signal will be integrated for further processing. The remaining signals are disregarded and only used for dead time correction.The remaining signals are disregarded and only used for dead time correction.

• Different settings are recommended for the upper and lower levels depending on which signal Different settings are recommended for the upper and lower levels depending on which signal you want to measure.you want to measure.

• Pulse shift Pulse shift is an effect that is caused by incoming X-rays. At very high count rates the analyte is an effect that is caused by incoming X-rays. At very high count rates the analyte signal partially shifts outside the selected PHD window. The electronics in the spectrometer signal partially shifts outside the selected PHD window. The electronics in the spectrometer correct for this effect using pulse shift correction which is designed to maintain stability. This correct for this effect using pulse shift correction which is designed to maintain stability. This ensures linearity between the measured or reported count rate and the actually absorbed count ensures linearity between the measured or reported count rate and the actually absorbed count rate. The magnitude of pulse shift depends on both the energy and the count rate of the rate. The magnitude of pulse shift depends on both the energy and the count rate of the absorbed flux (including the part which is not measured) in the detector.absorbed flux (including the part which is not measured) in the detector.

•

Theory of XRDTheory of XRDDiffract ion Crystals & Coll imators :Dif fract ion Crystals & Coll imators :

• A crystal can be seen as a stack of thin layers all having the same thickness. If a A crystal can be seen as a stack of thin layers all having the same thickness. If a parallel beam of X-Rays falls on the crystal ,the first layer reflects a fraction of the X-parallel beam of X-Rays falls on the crystal ,the first layer reflects a fraction of the X-Ray. The remaining radiation penetrates the crystal and is reflected by the Ray. The remaining radiation penetrates the crystal and is reflected by the subsequent layers. If the difference in path length between reflections from layers is subsequent layers. If the difference in path length between reflections from layers is multiple of half the wave length of the radiation, the two reflected beams vanish. If the multiple of half the wave length of the radiation, the two reflected beams vanish. If the difference is exactly an integer times the wavelength ,the two reflected beams re difference is exactly an integer times the wavelength ,the two reflected beams re inforce.The difference in path length is an integer times ,the wavelength if the inforce.The difference in path length is an integer times ,the wavelength if the following relation ,called Braggs law ,holds. Nλ= 2d sin (Ф)following relation ,called Braggs law ,holds. Nλ= 2d sin (Ф)

• At an angle ,all reflected radiation with a wavelength and obeying braggs law are in At an angle ,all reflected radiation with a wavelength and obeying braggs law are in phase and add up. All other wavelengths at the same angle will vanish,phase and add up. All other wavelengths at the same angle will vanish,

• A detector placed at angle can therefore measure the intensity of the corresponding A detector placed at angle can therefore measure the intensity of the corresponding wavelength. Reflected wavelengths obeying braggs law for n=1 are called first order wavelength. Reflected wavelengths obeying braggs law for n=1 are called first order reflection ,for n=2 second order .At any specific angle ,only radiation with a reflection ,for n=2 second order .At any specific angle ,only radiation with a wavelength obeying braggs law is reflected. Radiation with slightly different wavelength obeying braggs law is reflected. Radiation with slightly different wavelength will be reflected at slightly different angles ,but will still reach the detector wavelength will be reflected at slightly different angles ,but will still reach the detector and will interfere with the energy to be measured. A collimator ,which is set of parallel and will interfere with the energy to be measured. A collimator ,which is set of parallel plates ,is used to obtain a parallel X-Ray beam that falls exactly at the required angle plates ,is used to obtain a parallel X-Ray beam that falls exactly at the required angle on the crystal. the primary collimator is placed between the sample and crystal ,and on the crystal. the primary collimator is placed between the sample and crystal ,and on secondary collimator can be placed between the crystal and the detector.on secondary collimator can be placed between the crystal and the detector.

XRD: XRD:

Goniometer ,X Ray Tube (Ø1)-5 to 85 Ø ,Detector (-5 to 85 Ø ) 2Ø 0---167ØGoniometer ,X Ray Tube (Ø1)-5 to 85 Ø ,Detector (-5 to 85 Ø ) 2Ø 0---167Ø

X-Ray Tube (Ø----Ø Geometry) (Copper ,2200 W)X-Ray Tube (Ø----Ø Geometry) (Copper ,2200 W)

• ß Filter (Ni )ß Filter (Ni )

• Diversion Slit (1Ø)Diversion Slit (1Ø)

• Solar Slit (0.04 Radians)Solar Slit (0.04 Radians)

• Width Mask (10mm)Width Mask (10mm)

• SampleSample

• Fixed Anti scatter Slit (2Ø)Fixed Anti scatter Slit (2Ø)• Programmable Receiving Slit (0.1mm-3mm),Opening Increment 0.01 mmProgrammable Receiving Slit (0.1mm-3mm),Opening Increment 0.01 mm• Solar Slit (0.04 Radians)Solar Slit (0.04 Radians)• X-Celerator Detector (Combination of 100 Solid State detectors ,therefore X-Celerator Detector (Combination of 100 Solid State detectors ,therefore

processing time is 100 times fast)processing time is 100 times fast)

Equipment DetailsEquipment Details

Max MinWater Flow 6.0 l / min 3.5 l/minWater Input Pressure

50 PSI 115 PSI

Water Temperature

+ 35 c + 20 C

Compressed Air

6 Bar 4 Bar

Why use X-raysWhy use X-rays• There are various reasons why a choice is made for X-ray analysis:There are various reasons why a choice is made for X-ray analysis:• _ _ UniquenessUniqueness ofof thethe methodmethod• X-ray diffraction is very often the only technique available to analyse material X-ray diffraction is very often the only technique available to analyse material

properties, certainly when these depend on the crystalline state.properties, certainly when these depend on the crystalline state.• _ _ SpeedSpeed ofof analysisanalysis• Each measurement (analysis) can take only a few minutes, which allows a high Each measurement (analysis) can take only a few minutes, which allows a high

through-put of samples.through-put of samples.• XRF only takes XRF only takes one minute one minute for analysis of 09 elementsfor analysis of 09 elements• While XRD Takes While XRD Takes f ive & Half minutes f ive & Half minutes for analysis of for analysis of

C3S,C2S,C3A,C4AF,MaO.fCaO,KC3S,C2S,C3A,C4AF,MaO.fCaO,K22SOSO4 4 CLASSICAL CLASSICAL Method takes Method takes 06 Hrs 06 Hrs for Cement / for Cement / Clinker ,while at least Clinker ,while at least 12 Hours 12 Hours for Raw Materials. (Excluding Alkalis)for Raw Materials. (Excluding Alkalis)

• Non-destructiveNon-destructive analysisanalysis• Samples remain unchanged during and after measurement, which means that other Samples remain unchanged during and after measurement, which means that other

analysis techniques may be used on the same samples, or samples may be analysis techniques may be used on the same samples, or samples may be preserved when needed.preserved when needed.

• _ _ LargeLarge rangerange ofof materialsmaterials• All element from atomic weight 4 (Beryllium) with the exception of Nitrogen can be All element from atomic weight 4 (Beryllium) with the exception of Nitrogen can be

analysed with X-ray fluorescence.analysed with X-ray fluorescence.• All crystalline and semi-crystalline structures can be tested with X-ray diffraction, All crystalline and semi-crystalline structures can be tested with X-ray diffraction,

however no liquids can be analysed.however no liquids can be analysed.

Why use X-raysWhy use X-rays

• _ _ AccurateAccurate analysisanalysis• Relative accuracies of 0.1% to 0.3% are attainable.Relative accuracies of 0.1% to 0.3% are attainable.• _ _ Sensit ivitySensit ivity• With X-ray fluorescence elements can be detected in concentrations from 0.1 PPM up With X-ray fluorescence elements can be detected in concentrations from 0.1 PPM up

to 100 % (PPM = parts per million).to 100 % (PPM = parts per million).• With X-ray diffraction, crystalline structures can be analysed with a concentration of With X-ray diffraction, crystalline structures can be analysed with a concentration of

typically 0.1% up to 100%. In exceptional situations concentrations below 0.1% are typically 0.1% up to 100%. In exceptional situations concentrations below 0.1% are attainable.attainable.

• _ _ RangeRange ofof samplesample typestypes• Samples may be in many forms and shapes, with dimensions ranging from tens of Samples may be in many forms and shapes, with dimensions ranging from tens of

microns to meters.microns to meters.• _ _ EaseEase ofof useuse• Routine analyses do not require a high level of operator skills.Routine analyses do not require a high level of operator skills.• _ _ AutomatedAutomated operationoperation• The whole process of sample taking, sample preparation and the final measurement The whole process of sample taking, sample preparation and the final measurement

can can • sometimes be highly automated ensuring a high throughput of samples.sometimes be highly automated ensuring a high throughput of samples.

Uses of XRD & XRF :Uses of XRD & XRF :

1. Calculation of actual C3S,C2S,Ortho C3A,Cubic C3A ,C4AF,Mgo 1. Calculation of actual C3S,C2S,Ortho C3A,Cubic C3A ,C4AF,Mgo (Periclase) , Free Lime & K2S04 in Clinker.(Periclase) , Free Lime & K2S04 in Clinker.

2. Quartz in l imestone. 2. Quartz in l imestone. One major problem in cement manufacturing is achieving One major problem in cement manufacturing is achieving proper grindingproper grinding

and fineness of the material that is to enter the kiln. The presence of coarse quartz in and fineness of the material that is to enter the kiln. The presence of coarse quartz in limestonelimestone

can have an impact on both the parameters. Assessment of coarse quartz in raw can have an impact on both the parameters. Assessment of coarse quartz in raw feed can effectively be made by XRD in conjunction with acid treatment of the sample feed can effectively be made by XRD in conjunction with acid treatment of the sample and particle separation. The raw feed is treated with dilute hydrochloric acid until all and particle separation. The raw feed is treated with dilute hydrochloric acid until all carbonates have been decomposed. The residue is then filtered, dried, and analyzed carbonates have been decomposed. The residue is then filtered, dried, and analyzed by XRD. The XRD pattern showing quartz peaks gives an estimation of insoluble by XRD. The XRD pattern showing quartz peaks gives an estimation of insoluble quartz in the feed. Figure shows the XRD pattern of a raw feed prepared by this quartz in the feed. Figure shows the XRD pattern of a raw feed prepared by this procedure. Reference pattern lines superimposed on the sample’s pattern indicate procedure. Reference pattern lines superimposed on the sample’s pattern indicate the position and intensity for major quartz peaks.the position and intensity for major quartz peaks.

Uses of XRD & XRF:Uses of XRD & XRF: (XRD Pattern of KF treated with HCL Filtered & dried)(XRD Pattern of KF treated with HCL Filtered & dried)

Uses of XRD & XRF:Uses of XRD & XRF:

• Additionally, if the insoluble residue is sieved through a No. 325 sieve, and the XRD Additionally, if the insoluble residue is sieved through a No. 325 sieve, and the XRD pattern of the portion retained on the sieve is obtained, abundance of quartz coarser pattern of the portion retained on the sieve is obtained, abundance of quartz coarser than 45 µm can be estimated from this fraction. Figure shows the XRD pattern of a than 45 µm can be estimated from this fraction. Figure shows the XRD pattern of a coarse fraction obtained after acid treatment of a cement raw feed. It is apparent that coarse fraction obtained after acid treatment of a cement raw feed. It is apparent that this kiln feed sample has a relatively high amount of coarse quartz .Because quartz is this kiln feed sample has a relatively high amount of coarse quartz .Because quartz is harder to grind than other materials in the raw feed and is harder to burn, it is likely harder to grind than other materials in the raw feed and is harder to burn, it is likely that cement produced with this kiln feed will contain belite clusters formed during that cement produced with this kiln feed will contain belite clusters formed during clinkering process. Raw feed containing coarse quartz will require more grinding clinkering process. Raw feed containing coarse quartz will require more grinding energy to produce a quality clinker.energy to produce a quality clinker.

XRD pattern of ki ln feed sample treated with di luted HCl, f i l tered, XRD pattern of ki ln feed sample treated with di luted HCl, f i l tered, dried, and sieved through a 45 µm-size sieve. Reference l ines for dried, and sieved through a 45 µm-size sieve. Reference l ines for quartz are shown.quartz are shown.

Uses of XRD & XRF:Uses of XRD & XRF:• Gypsum RockGypsum Rock

In the sense that gypsum is added to clinker during inter grinding in the finish mill, it is considered a In the sense that gypsum is added to clinker during inter grinding in the finish mill, it is considered a raw material in cement manufacturing. Its purpose is to control setting when the cement starts raw material in cement manufacturing. Its purpose is to control setting when the cement starts to hydrate. Gypsum is generally secured from naturally occuring deposits in the earth In natural to hydrate. Gypsum is generally secured from naturally occuring deposits in the earth In natural gypsum deposits, it is most useful to scan the source for naturally occurring anhydrite(CaSO4) gypsum deposits, it is most useful to scan the source for naturally occurring anhydrite(CaSO4) or anhydrous calcium sulfate. Since this form of calcium sulfate is not as readily soluble in water or anhydrous calcium sulfate. Since this form of calcium sulfate is not as readily soluble in water as is gypsum (CaSO4• 2H2O), anhydrite can fail to control concrete setting appropriately. In as is gypsum (CaSO4• 2H2O), anhydrite can fail to control concrete setting appropriately. In addition, anhydrite is much harder than gypsum and will not be ground as fine during finish addition, anhydrite is much harder than gypsum and will not be ground as fine during finish grinding; this will also reduce its rate of solubility. For these reasons, sources of gypsum grinding; this will also reduce its rate of solubility. For these reasons, sources of gypsum containing high amounts of anhydrite are usually avoided. However, if the finish mill containing high amounts of anhydrite are usually avoided. However, if the finish mill temperature is very high, dehydration of gypsum might produce too much hemihydrate (CaSO4• temperature is very high, dehydration of gypsum might produce too much hemihydrate (CaSO4• 1⁄2H2O), there by causing false set. In such a case, it may be desirable to add some of the 1⁄2H2O), there by causing false set. In such a case, it may be desirable to add some of the needed calcium sulfate as anhydrite. XRD provides a quick method to detect anhydrite together needed calcium sulfate as anhydrite. XRD provides a quick method to detect anhydrite together with coexisting gypsum,hemihydrate, and minor contamination such as calcite and quartz. with coexisting gypsum,hemihydrate, and minor contamination such as calcite and quartz. Figure shows an XRD pattern of a gypsum source. Naturally occurring anhydrite, sometimes Figure shows an XRD pattern of a gypsum source. Naturally occurring anhydrite, sometimes referred to as “insoluble” anhydrite, differs from “soluble” anhydrite in that they have different referred to as “insoluble” anhydrite, differs from “soluble” anhydrite in that they have different crystalline arrangements and therefore have slightly different solubility in water. “Soluble” crystalline arrangements and therefore have slightly different solubility in water. “Soluble” anhydrite can result, for instance when gypsum is exposed to temperatures above around anhydrite can result, for instance when gypsum is exposed to temperatures above around 200°C and loses its chemically bound water. This compound is not200°C and loses its chemically bound water. This compound is not

XRD pattern of gypsum rock source for addit ion to cl inker in cement XRD pattern of gypsum rock source for addit ion to cl inker in cement grinding. In addit ion to gypsum (reference l ines shown), phases identif ied grinding. In addit ion to gypsum (reference l ines shown), phases identif ied include hemihydrate (Hh) and quartz (Qz). I t must be not iced that include hemihydrate (Hh) and quartz (Qz). I t must be not iced that hemihydrate does not usual ly occur naturally. I ts presence in this pattern hemihydrate does not usual ly occur naturally. I ts presence in this pattern may result from sample preparation.may result from sample preparation.


• easily distinguished from plaster by XRD in gypsum sources but is rapidly soluble and easily distinguished from plaster by XRD in gypsum sources but is rapidly soluble and usually causes no interference in controlling concrete setting.usually causes no interference in controlling concrete setting.

• Coal CharacterizationCoal Characterization• The principal solid fuel used in cement manufacture is coal. In addition to clay The principal solid fuel used in cement manufacture is coal. In addition to clay

minerals, common impurities in coal are carbonates, iron sulfides such as pyrite minerals, common impurities in coal are carbonates, iron sulfides such as pyrite (FeS2) and other sulfides, chlorides ,and quartz (Bye, 1999). XRD is a useful tool for (FeS2) and other sulfides, chlorides ,and quartz (Bye, 1999). XRD is a useful tool for detecting these compounds. Sulfides and chlorides can cause a variety of problems detecting these compounds. Sulfides and chlorides can cause a variety of problems when coal is burned in the kiln or in the calciner. The use of coals(and fuels in when coal is burned in the kiln or in the calciner. The use of coals(and fuels in general) is limited by the total sulfur content, and some sulfur is in the form of general) is limited by the total sulfur content, and some sulfur is in the form of crystalline sulfides, XRD will be a useful tool for detecting these compounds. crystalline sulfides, XRD will be a useful tool for detecting these compounds. Chlorides also may be present in crystalline structures like sylvite or halite that can Chlorides also may be present in crystalline structures like sylvite or halite that can easily be detected by XRD. Pyrite is found in coal as a common impurity and in some easily be detected by XRD. Pyrite is found in coal as a common impurity and in some limestone deposits as well. Its XRD peaks are located at 33.0X, 56.27, 37.15, and limestone deposits as well. Its XRD peaks are located at 33.0X, 56.27, 37.15, and 40.74 °2θ.40.74 °2θ.


• Dolomitic LimestonesDolomitic LimestonesDolomite (CaMg(CO3)2) has limited use in cement manufacturing because the clinker Dolomite (CaMg(CO3)2) has limited use in cement manufacturing because the clinker

resulting from its use would be excessively high in free MgO or periclase upon clinker resulting from its use would be excessively high in free MgO or periclase upon clinker cooling. Potential problems may arise with these cements because of their excessive cooling. Potential problems may arise with these cements because of their excessive expansion. However, some cement producers have dealt with high MgO clinkers by expansion. However, some cement producers have dealt with high MgO clinkers by adjusting the raw mix chemistry to produce a clinker with a lower MgO/Fe2O3 ratio. adjusting the raw mix chemistry to produce a clinker with a lower MgO/Fe2O3 ratio. As a rule of thumb, when this ratio is lower, more MgO can be tolerated without failing As a rule of thumb, when this ratio is lower, more MgO can be tolerated without failing the autoclave expansion test. At certain cement-making locations the only limestone the autoclave expansion test. At certain cement-making locations the only limestone readily available may contain appreciable dolomite, and in such cases, careful readily available may contain appreciable dolomite, and in such cases, careful characterization of the limestone is required. In the example shown in Figure, the characterization of the limestone is required. In the example shown in Figure, the limestone contains a rather high proportion of dolomite, whose XRD reference lines limestone contains a rather high proportion of dolomite, whose XRD reference lines are shown in the pattern. A cement or clinker suspected of containing high MgO are shown in the pattern. A cement or clinker suspected of containing high MgO should be analyzed by XRD. Chemical analysis is also desirable. Clinkers or cements should be analyzed by XRD. Chemical analysis is also desirable. Clinkers or cements high in MgO may contain as much as 8% or as little as 3.5% periclase by mass. high in MgO may contain as much as 8% or as little as 3.5% periclase by mass. Figure shows a clinker sample with an unusual amount of periclase, readily identified Figure shows a clinker sample with an unusual amount of periclase, readily identified by the diffraction line at 42.9 °2θ.by the diffraction line at 42.9 °2θ.

XRD pattern of a sample of l imestone high in dolomite used as XRD pattern of a sample of l imestone high in dolomite used as a source in cement manufacturing. Reference l ines for dolomite a source in cement manufacturing. Reference l ines for dolomite are shown. Labels for quartz (Qz) and calcite (Cc)main peaks are shown. Labels for quartz (Qz) and calcite (Cc)main peaks are also shown.are also shown.

XRD pattern of cement containing free MgO or crystal l ine XRD pattern of cement containing free MgO or crystal l ine Periclase (reference l ines shown). The oxide analysis reported a Periclase (reference l ines shown). The oxide analysis reported a total MgO of 3.9 wt.%.total MgO of 3.9 wt.%.


• ClayClay• Clay materials from quarries used in cement manufacturing normally occur together Clay materials from quarries used in cement manufacturing normally occur together

with feldspars,quartz, and carbonates (calcite or dolomite). The XRD is an essential with feldspars,quartz, and carbonates (calcite or dolomite). The XRD is an essential tool, aided by optical microscopy and chemical analysis, to characterize and identify tool, aided by optical microscopy and chemical analysis, to characterize and identify clay components in cement raw materials. Clay minerals have a layered crystal clay components in cement raw materials. Clay minerals have a layered crystal structure and often occur as thin sheets parallel to these crystal layers. Clays are structure and often occur as thin sheets parallel to these crystal layers. Clays are often poorly crystalline and often occur as very small grains. For these reasons, their often poorly crystalline and often occur as very small grains. For these reasons, their basal peak (from the crystal layer) is often the only recognizable peak and may be basal peak (from the crystal layer) is often the only recognizable peak and may be quite broad. The d-spacing of the basal peak is usually quite broad, a feature that is quite broad. The d-spacing of the basal peak is usually quite broad, a feature that is very helpful for their identification in the presence of minerals like quartz, feldspars, or very helpful for their identification in the presence of minerals like quartz, feldspars, or carbonates. For instance, a diffraction peak at 12.3 °2θ identifies kaolinite, usually carbonates. For instance, a diffraction peak at 12.3 °2θ identifies kaolinite, usually indicative of kaolin clay present in the overburden of limestone quarries. Another clay indicative of kaolin clay present in the overburden of limestone quarries. Another clay commonly found is illite. An example of the XRD pattern on clay minerals identified commonly found is illite. An example of the XRD pattern on clay minerals identified ina clay source for cement manufacturing is shown in Figure.ina clay source for cement manufacturing is shown in Figure.

XRD pattern showing clay minerals identif ied on a clay source XRD pattern showing clay minerals identif ied on a clay source for cement manufacturing. Cc: calcite, Qz: quartz, Mm: for cement manufacturing. Cc: calcite, Qz: quartz, Mm:

montmoril lonite, Ch: chlorite,Ab: montmoril lonite, Ch: chlorite,Ab: albite, Mt: margarite.albite, Mt: margarite.


• LimestoneLimestone• Limestone is the main raw material used in cement manufacturing. It comprises from Limestone is the main raw material used in cement manufacturing. It comprises from

70% to 95% of the raw meal fed to the kiln. Calcite (CaCO3) is normally the most 70% to 95% of the raw meal fed to the kiln. Calcite (CaCO3) is normally the most abundant phase in limestone; its strongest diffraction peak is produced at 29.4 °2θ abundant phase in limestone; its strongest diffraction peak is produced at 29.4 °2θ with Cu Kα radiation6. Quartz, feldspars, and clay minerals are normally present as with Cu Kα radiation6. Quartz, feldspars, and clay minerals are normally present as minor contaminants in limestone deposits. Dolomite is also found in small amounts in minor contaminants in limestone deposits. Dolomite is also found in small amounts in some limestones , as discussed later in this section. Figure shows a typical XRD some limestones , as discussed later in this section. Figure shows a typical XRD pattern of limestone.pattern of limestone.

XRD pattern of a l imestone sample from a quarry. Calcite XRD pattern of a l imestone sample from a quarry. Calcite (reference l inesshown7) and quartz detected as main phases. (reference l inesshown7) and quartz detected as main phases.

Aluminum line from sample holder is also shownAluminum line from sample holder is also shownas an art ifact.as an art ifact.


• BauxiteBauxite• Bauxite may be used in cement manufacturing in cases where lime and/or silica Bauxite may be used in cement manufacturing in cases where lime and/or silica

sources do not provide enough Al2O3 for the desired clinker formulation. Bauxite’s sources do not provide enough Al2O3 for the desired clinker formulation. Bauxite’s mineralogical composition also includes different polymorphs of aluminum oxide and mineralogical composition also includes different polymorphs of aluminum oxide and hydroxide, such as gibbsite, norstrandite, and bayerite, which are readily identifiable hydroxide, such as gibbsite, norstrandite, and bayerite, which are readily identifiable by XRD. Bauxite may also contain hematite and magnetite, which incorporate iron by XRD. Bauxite may also contain hematite and magnetite, which incorporate iron into the clinker. Corundum (Al2O3), is also readily identifiable. It is a very hard into the clinker. Corundum (Al2O3), is also readily identifiable. It is a very hard mineral and its identification is a decisive factor for raw feed grindability mineral and its identification is a decisive factor for raw feed grindability considerations. Al(OH)3, as the main phase in the sample. particular sample is considerations. Al(OH)3, as the main phase in the sample. particular sample is primarily composed of a mixture of gibbsite (reference lines shown) and hematite primarily composed of a mixture of gibbsite (reference lines shown) and hematite (peaks at 33.1X, 35.67, 24.13 °2θ). It also contains anatase (TiO2), aluminum oxide(peaks at 33.1X, 35.67, 24.13 °2θ). It also contains anatase (TiO2), aluminum oxide

hydroxide, or boehmite (Al O(OH)), and traces of calcite, quartz, and kaolinite.hydroxide, or boehmite (Al O(OH)), and traces of calcite, quartz, and kaolinite.

Bauxite alternative alumina source for cement manufacturing. Bauxite alternative alumina source for cement manufacturing. Reference l ines shown identify gibbsite as the main crystall ine Reference l ines shown identify gibbsite as the main crystall ine

component in the sample.component in the sample.

XRD graph of an alternative alumina source for cement XRD graph of an alternative alumina source for cement manufacturing. The sample consists of a mixture of gibbsite and manufacturing. The sample consists of a mixture of gibbsite and

hematite. Reference l ines shown identify gibbsite.hematite. Reference l ines shown identify gibbsite.

Bauxite PlotBauxite Plot

Clay PlotClay Plot

Gypsum PlotGypsum Plot

Laterite PlotLaterite Plot

Limestone PlotLimestone Plot

Sand stone Low PuritySand stone Low Purity

Sand stone High PuritySand stone High Purity

Raw Mix Quartz TestRaw Mix Quartz Test

XRF & XRD Analysis Principle

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