PROJECT ON PROPYLENE OXIDE MAHATMA GANDHI MISSION’S COLLEGE OF ENGINEERING & TECHNOLOGY KAMOTHE, NAVI MUMBAI. ACADEMIC YEAR: 2011-2012. PROJECT REPORT ON MANUFACTURE OF “PROPYLENE OXIDE” UNDER THE GUIDANCE OF Prof.: CYRUS K MISTRY SUBMITTED BY- MIKHIL MOHAN VINEET G. NAIR 1 MGM COLLEGE OF ENGINEERING AND TECHNOLOGY
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PROJECT ON PROPYLENE OXIDE
MAHATMA GANDHI MISSION’S
COLLEGE OF ENGINEERING & TECHNOLOGY
KAMOTHE, NAVI MUMBAI.
ACADEMIC YEAR: 2011-2012.
PROJECT REPORT
ON
MANUFACTURE OF “PROPYLENE OXIDE”
UNDER THE GUIDANCE OF
Prof.: CYRUS K MISTRY
SUBMITTED BY-
MIKHIL MOHAN
VINEET G. NAIR
1MGM COLLEGE OF ENGINEERING AND TECHNOLOGY
PROJECT ON PROPYLENE OXIDE
Department of Chemical Engineering
MAHATMA GANDHI MISSION’S
COLLEGE OF ENGINEERING & TECHNOLOGY
KAMOTHE, NAVI MUMBAI.
CERTIFICATE
This is to certify that the following students,
MIKHIL MOHAN
VINEET G. NAIR
have successfully completed the project report entitled “PROPYLENE OXIDE” during
the prescribed period in the academic year 2011-12. This Project report is submitted in
the partial fulfillment of “BACHELOR OF CHEMICAL ENGINEERING” of Mumbai
University.
GUIDE EXTERNAL EXAMINER
HEAD OF DEPARTMENT PRINCIPAL
2MGM COLLEGE OF ENGINEERING AND TECHNOLOGY
PROJECT ON PROPYLENE OXIDE
ACKNOWLEDGEMENTS
This project would never have seen the light of the day if it hadn’t been for support and
encouragement of multitude of very exemplary people.
We would like to sincerely thank my guide & Head of Chemical Engineering Department Dr.
CYRUS K MISTRY who is the driving force behind this project and discussion with him
proved to be enlightening.
We express our sincere gratitude toward our principal Dr. GEETHA JAYARAJ, for
providing us with the opportunity to chose this project. We would be failing our duty if we do
not acknowledge the help extended by professors of Chemical Department of MGM’S
college of engineering and technology. Our heartfelt gratitude to library and their staff
member.
MIKHIL MOHAN
VINEET G. NAIR
3MGM COLLEGE OF ENGINEERING AND TECHNOLOGY
PROJECT ON PROPYLENE OXIDE
4MGM COLLEGE OF ENGINEERING AND TECHNOLOGY
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Sr. No. Topic Page No.
1 Introduction 4
2 Physical and Chemical Properties
2.1 Physical Data
2.2 Chemical Reactions
7
3 Manufacturing Processes
3.1 Chlorohydrin Process
3.2 Hydroperoxide Process
12
4 Process Selection And Description
4.1 Raw Materials Used
4.2 Flowsheet and Process Description
16
5 Manufacturers of Propylene Oxide in
India
23
6 Applications And Uses
6.1 Derivatives
25
7 Material Safety Data Sheet
7.1 Hazard Identification
7.2 Primary Routes of Exposure
7.3 Signs and Symptoms of Over Exposure
7.4 Acute Health Effects
7.5 Chronic Health Effects
7.6 First Aid Measures
7.7 Handling and Storage
7.8 Disposal Considerations
29
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Chapter 1
Introduction
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Introduction of Propylene Oxide
Propylene Oxide (PO) is a highly reactive chemical used as an
intermediate for the production of numerous commercial materials. It reacts
readily with compounds containing active hydrogen atoms such as alcohols,
amines and acids.
Its main derivatives include polyether polyols, propylene glycol (PG) and
propylene glycol ethers but it has many other outlets. Propylene oxide is used in
the production of poly-ethers (the primary component of polyurethane foams)
and propylene glycol.
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Acute (short-term) exposure of humans and animals to propylene oxide
has caused eye and respiratory tract Irritation. Dermal contact, even with dilute
solutions, has caused skin irritation and necrosis in humans. Propylene oxide is
also a mild Central Nervous System (CNS) depressant in humans.
Inflammatory lesions of the nasal cavity, trachea, and lungs and neurological
effects have been observed in animals chronically (long-term) exposed to
propylene oxide by inhalation. Propylene oxide has been observed to cause
tumors at or near the site of administration in rodents, causing forestomach
tumors following ingestion via gavage (experimentally placing the chemical in
the stomach) and nasal tumors after inhalation exposure. EPA has classified
propylene oxide as a Group B2, probable human carcinogen.
Other applications for PO include hydroxypropyl acrylates used in UV
curable resins, inks, coatings and varnishes; iso-propanolamines employed as
solvents in natural gas purification, metal working fluids and cosmetics; and
propylene glycol alginates made with sea weed (kelp) for use as food grade
thickeners, emulsifiers and stabilisers.
Global demand for PO had been growing at 4-5%/year. Growth in Europe
and the US had been around 3-4%/year while Asia, in particular China, had
seen the strongest growth at 7-8%/year.
In addition, growth came to an abrupt halt when markets collapsed in the
second half of 2008 due to the economic crisis. Overall sales were said to be 5%
down in 2008 compared to 2007 and a further decline of 5% is expected in
2009. As a result much capacity has been temporarily idled in this period.
Markets are not expected to return to pre-crisis growth levels until 2011,
according to some market sources.
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Chapter 2
CHEMICAL AND
PHYSICAL
PROPERTIES
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2.1 Physical Properties
Propylene oxide is a colorless, low-boiling (34.2 °C) liquid. Table 1 lists
general physical properties. Table 2 provides equations for temperature
variation on some thermodynamic functions. Vapor-liquid equilibrium data for
binary mixtures of propylene oxide and other chemicals of commercial
importance are available. References for binary mixtures include 1, 2-
1999. Catalytic dehydrogenation of the ethylbenzene then gives hydrogen and
styrene:
C6H5CH2CH3 → C6H5CH=CH2 + H2
Properties of Ethylbenzene
Property Value
Appearance Liquid
Odour Sweet, Aromatic
Colour Transparent, Colourless
Molecular Weight 106.17
Density at 20 oC 868 kg/m3
Boiling Point at 1013 hPa 136.2 oC
Freezing Point -95 oC
Kinematic Viscosity at 10 oC 0.9 mm2/s
Dynamic Viscosity at 10 oC 0.78 m-Pas
Critical Pressure 3.701 mPa
Critical Temperature 343.05 oC
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4.2.2 Flowsheet and Process Description:
Figure above shows the process flow sheet for production of propylene
oxide and styrene via the use of ethylbenzene hydroperoxide (EBHP). Liquid-
phase oxidation of ethylbenzene with air or oxygen occurs at 206–275 kPa (30 –
40 psia) and 140 150 oC, and 2–2.5 hrs. are required for a 10–15% conversion to
the hydroperoxide. Recycle of an inert gas, such as nitrogen, is used to control
reactor temperature. Impurities in the ethylbenzene, such as water, are
controlled to minimize decomposition of the hydroperoxide product and are
sometimes added to enhance product formation. Selectivity to by-products
include 8–10% acetophenone, 5–7% 1-phenylethanol, and <1% organic acids.
EBHP is concentrated to 30–35% by distillation. The overhead ethylbenzene is
recycled back to the oxidation reactor. Because the by-product organic acids
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decompose EBHP and decrease epoxidation catalyst activity, an alkali
hydroxide or carbonate wash is used to neutralize the acids.
EBHP is mixed with a catalyst solution and fed to a horizontal
compartmentalized reactor where propylene is introduced into each
compartment. The reactor operates at 95–130◦C and 2500–4000 kPa (360–580
psi) for 1–2 h, and 5–7 mol propylene/1 mol EBHP are used for a 95–99%
conversion of EBHP and a 92–96% selectivity to propylene oxide. The
homogeneous catalyst is made from molybdenum, tungsten, or titanium and an
organic acid, such as acetate, naphthenate, stearate, etc. Heterogeneous catalysts
consist of titanium oxides on a silica support.
After epoxidation, propylene oxide, excess propylene, and propane are
distilled overhead. Propane is purged from the process; propylene is recycled to
the epoxidation reactor. The bottoms liquid is treated with a base, such as
sodium hydroxide, to neutralize the acids. Acids in this stream cause
dehydration of the 1- phenylethanol to styrene. The styrene readily polymerizes
under these conditions. Neutralization, along with water washing, allows phase
separation such that the salts and molybdenum catalyst remain in the aqueous
phase. Dissolved organics in the aqueous phase are further recovered by
treatment with sulfuric acid and phase separation. The organic phase is then
distilled to recover 1-phenylethanol overhead. The heavy bottoms are burned
for fuel. Crude propylene oxide separated from the epoxidation reactor effluent
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is further purified by a series of conventional and extractive distillations to
reduce the content of aldehydes, ethylbenzene, water, and acetone.
The co-product 1-phenylethanol from the epoxidation reactor, along with
acetophenone from the hydroperoxide reactor, is dehydrated to styrene in a
vapor-phase reaction over a catalyst of silica gel or titanium dioxide at 250–280 oC and atmospheric pressure. This product is then distilled to recover purified
styrene and to separate water and high-boiling organics for disposal. Unreacted
1-phenyl ethanol is recycled to the dehydrator.
Acetophenone is separated for hydrogenation to 1-phenylethanol, which
is sent to the dehydrator to produce styrene. Hydrogenation is done over a fixed-
bed copper-containing catalyst at 115–120 oC and pressure of 8100 kPa (80
atm), a 3:1 hydrogen-to-acetophenone ratio, and using a solvent such as ethyl
benzene, to give 95% conversion of the acetophenone and 95% selectivity to 1-
phenyl ethanol.
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Chapter 5
Manufacturers of
Propylene Oxide in
India
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Triveni Interchem Pvt. Ltd. in Vapi, Gujarat, India.
Mulberry Chemicals Pvt. Ltd. in Mumbai, India.
Suyash Herbs Export Private Limited in Surat, India.
Arihant Chemicals in Mumbai, India.
Alpha Chemika in Mumbai, India.
Taj Pharmaceuticals Ltd. in Mumbai, India.
Ksm Intertrade Agencies in Mumbai, India.
Desmo Exports Ltd in Mumbai, India.
N. R. Chemicals Corporation in Dewas, Madhya Pradesh, India.
Chemix Speciality Gases And Equipments in Bangalore, India.
Excel International in Mumbai, India.
Sri Jayalaxmi Traders in Arcot, Tamil Nadu, India.
Intersperse Industries in Ahmedabad, Gujarat, India.
Sunn Chhem in Pune, India.
Bnh Gas Tank in Pune, India.
Darshit Impex in Ahmedabad, India.
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Chapter 6
APPLICATIONS
AND USES
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Propylene oxide is a useful chemical intermediate. Additionally, it has
found use for etherification of wood to provide dimensional stability, for
purification of mixtures of organo-silicon compounds, for disinfection of crude
oil and petroleum products, for sterilization of medical equipment and
disinfection of foods, and for stabilization of halogenated organics.
Propylene oxide has found use in preparation of polyether polyols from
recycled poly (ethylene terephthalate), halide removal from amine salts via
halohydrin formation, preparation of flame retardants, alkoxylation of amines,
modification of catalysts, and preparation of cellulose ethers.
6.1 Derivatives:
6.1.1 Polyether Polyols:
Polyether polyols produced by polymerization of propylene oxide on
polyhydric alcohols account for the largest use of propylene oxide. The starting
polyhydric alcohols have from two to eight hydroxyl groups and can be
mixtures of two or more alcohols. Molecular weights of the products range from
about 400 to about 8000. Some of the polyether polyols may be made with
copolymerization of ethylene oxide. The ethylene oxide can either be in blocks
or randomly distributed in the polymer. The products are useful for making
flexible and rigid urethane foams, adhesives, coatings, sealants, and reaction
moldable products.
6.1.2 Propylene Glycol:
Propylene glycol, the second largest use of propylene oxide, is produced
by hydrolysis of the oxide with water. Propylene glycol has very low toxicity
and is, therefore, used directly in foods, pharmaceuticals, and cosmetics, and
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indirectly in packaging materials. Propylene glycol also finds use as an
intermediate for numerous chemicals, in hydraulic fluids, in heat transfer fluids
(antifreeze), and in many other applications.
Dipropylene glycol is produced in the manufacture of propylene glycol
and finds utility as an indirect food additive, in brake-fluid formulations, cutting
oils, soaps, and solvents. Tripropylene glycol also finds use as a solvent, as
textile soaps, and as lubricants.
6.1.3 Poly (propylene glycol):
Polymers of propylene oxide based on reaction with water or propylene
glycol are liquids of 400 to about 4000 molecular weight. Viscosity increases
and water solubility decreases with increasing molecular weight.
Poly(propylene glycol)s find use in cosmetics, as synthetic lubricants, as
metalworking fluids, antifoam agents, heat transfer fluids, nonionic surfactants,
and chemical intermediates.
6.1.4 Glycol Ethers:
Glycol ethers are produced by reaction of propylene oxide with various
alcohols such as methanol, ethanol, butanol, and phenol. The products are
themono-, di-, and tripropylene glycol ethers. These products are used in