Seminar

11

22

SeminarSeminar

Chemical Methods for Electronic Wastes Chemical Methods for Electronic Wastes RecoveryRecovery

Supervisor: Professor H. S. GhaziaskarSupervisor: Professor H. S. Ghaziaskar

Department of Chemistry Department of Chemistry

Isfahan University of TechnologyIsfahan University of Technology

Gholamhossein Paniri

33

ContentContent

What is electronic wastesWhat is electronic wastes

Why E-Wastes are recyclingWhy E-Wastes are recycling

E-waste recycling stepsE-waste recycling steps

Methods of materials chemical recoveryMethods of materials chemical recovery

ConclusionsConclusions

ReferencesReferences

44

What is Electronic Waste?What is Electronic Waste?

Electronic WasteElectronic Waste E- Waste

55

Why E-Waste Recycling???Why E-Waste Recycling???

H.-Y. Kang, J.M. Schoenung / Resources, Conservation and Recycling 45 (2005)

CRT CRT 12%12%

Metals 49%Metals 49%Plastics 33%Plastics 33%

Others 6%Others 6%

66

Types material of E-WasteTypes material of E-Waste

precious metalsprecious metals

hazardous materialhazardous material

77

Electronic Electronic waste scrapwaste scrap FeFe CuCu AlAl PbPb ZnZn AgAg AuAu PdPd

PCPC 77 2020 55 1.51.5 11 1010 2525 1111

MobileMobile

PhonePhone

55 1313 11 0.30.3 0.10.1 13.813.8 3535 2121

DVDDVD

PlayerPlayer

2323 55 22 0.30.3 0.050.05 11.511.5 1.51.5 44

CalculatorCalculator 6262 33 55 0.10.1 0.50.5 2.62.6 55 55

PrinterPrinter 4.54.5 1010 77 1.21.2 0.850.85 2.82.8 1111 00

TVTV 00 3.43.4 1.21.2 0.20.2 0.0380.038 0.290.29 0.120.12 33

CRTCRT 2828 1010 1010 11 0.30.3 0.280.28 0.20.2 00

Weight Percent of Metals in different Electronic Wastes Weight Percent of Metals in different Electronic Wastes

J. Cui, L. Zhang / Journal of Hazardous Materials 158 (2008) 228–256

88Pri= the current price of metal i

Vi= Value distribution

Wti= Weight precent of metal i in the electronic scrap sample

VVii==100100 WtWtiiPrPrii

WtWtiiPrPrii∑∑

99

Electronic Electronic waste scrapwaste scrap

FeFe CuCu AlAl PbPb ZnZn AgAg AuAu PdPd Sum of Sum of

Prcious Prcious metalsmetals

PricesPrices

($/ ton )($/ ton )

300300 77367736 24752475 35803580 3115031150 430000430000 2449000024490000 1166000011660000 ──

PCPC 00 1616 11 11 33 44 6262 1313 7979

Mobile phoneMobile phone 00 88 00 00 00 55 6767 1919 9191

DVD playerDVD player 1717 3535 11 11 11 44 3333 22 4242

CalculatorCalculator 11 1212 00 00 88 66 6464 44 7373

PrinterPrinter 11 1919 44 11 66 33 6666 88 6969

TVTV 00 8282 99 22 44 33 00 00 33

CRTCRT 44 3939 1313 22 55 66 2525 66 3737

Value-ShareValue-Share(%) (%)

a The metal price data are from London Metal Exchange (LME) official prices for cash seller and settlement on the 24th October, 2007.

1010

Toxic Content of E-waste

1111

7.24 kg7.24 kg PlasticPlastic 14/427/000 kg14/427/000 kg

1.98 kg1.98 kg LeadLead 3/962/700 kg3/962/700 kg

9.92g9.92g BariumBarium 19/845kg19/845kg

4.94g4.94g BerylliumBeryllium 9/891kg9/891kg

2.961g2.961g CadmiumCadmium 5/922 Kg5/922 Kg

1.981 g1.981 g ChromiumChromium 3/969kg3/969kg

0.693g0.693g MercuryMercury 1/386kg1/386kg

0.4095g0.4095g ArsenicArsenic 819kg819kg

E-waste hazardsE-waste hazards

Average pc of approx. 31.5 kgAverage pc of approx. 31.5 kg Two million obsoleteTwo million obsolete

Wt. contains Pcs world meanWt. contains Pcs world mean

www.toxicslink.org

1212

Scope of the problemScope of the problem

Rapidly growing E-waste streamRapidly growing E-waste stream2002 4.52002 4.5

2005 32005 3

2009 22009 2

H.-Y. Kang, J.M. Schoenung / Resources, Conservation and Recycling 45 (2008) 368–400

1313

Why recycling E-waste?Why recycling E-waste?

1.E-Waste large amount of precious1.E-Waste large amount of precious metalsmetals

2.E-Waste contain hazardous material2.E-Waste contain hazardous material

3.E-Waste is a huge secondary3.E-Waste is a huge secondary resourceresource above (mine ground) should notabove (mine ground) should not wastedwasted

1414

E-waste recycling contentE-waste recycling content

1.Ban export and disposal as well as incineration 1.Ban export and disposal as well as incineration landfillinglandfilling

2.Advertisement for recycling2.Advertisement for recycling

3.Collection and transportation3.Collection and transportation

4.Market for reuse4.Market for reuse

5.Materials recovery facility (MRF)5.Materials recovery facility (MRF)

Resources, Conservation and Recycling 45 (2005) 368–400

1515

Ban export and disposalBan export and disposal

The Basel conventionThe Basel convention

Disposal = reuse + recyclingDisposal = reuse + recycling

Hong Hong KongKong

VietnamVietnam ThailandThailand MalaysiaMalaysia ChainaChaina CambodiaCambodia KoreaKorea OthersOthers

13549631354963 197815197815 6532365323 2726427264 1444014440 1301113011 85988598 1801518015

The amount of secondhand The amount of secondhand personal computerpersonal computer exported from Japan in 2005 exported from Japan in 2005

Hong Hong KongKong

VietnamVietnam CambodiaCambodia MalaysiaMalaysia MyenmarMyenmar ChainaChaina ThailandThailand OthersOthers

2835628356 658293658293 281124281124 167723167723 166010166010 9277992779 3546335463 4525945259

The amount of seconhand The amount of seconhand television television exported from Japan in 2005exported from Japan in 2005

1616

Advertisement and sortingAdvertisement and sorting

AdvertisementAdvertisement

Sorting

1717

Collection and transportationCollection and transportation

1818

Market for reuseMarket for reuseMRFMaterials Recovery Facility

1919

Electronic Waste in IRANElectronic Waste in IRAN

2020

2121

Materials recovery of chemical methodsMaterials recovery of chemical methods

1. percious metals Recovery1. percious metals Recovery

2. hazardous materials Recovery2. hazardous materials Recovery

2222

Precious metals recoveryPrecious metals recovery

1.Pyrometallurgical1.Pyrometallurgical

2.Hydrometallurgical2.Hydrometallurgical

2323

Recovery of precios metals from E- waste by Recovery of precios metals from E- waste by pyrometallurgical processingpyrometallurgical processing

1.Incineration1.Incineration

2.Smelting in a blast furnace2.Smelting in a blast furnace

3.Drossing3.Drossing

4.Sintering4.Sintering

5.Reaction in a gas phase at high tempertures5.Reaction in a gas phase at high tempertures

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TechniquesTechniques Metals recoveredMetals recovered Main resultsMain results

Noranda process at canadaNoranda process at canada Cu, Au,Pt,Pd,Se,Te,ZnCu, Au,Pt,Pd,Se,Te,Zn High recovery for CopperHigh recovery for Copper

Boliden RÖnnskarBoliden RÖnnskar Cu,Ag,Au,Pd,Zn,PbCu,Ag,Au,Pd,Zn,Pb High recovery of High recovery of

Percious metalsPercious metals

UmicoreUmicore precious metal precious metal refiningrefining

Cu,Ag,Pt,Pd,AuCu,Ag,Pt,Pd,Au Almost complete recoveryAlmost complete recovery

Of CopperOf Copper

Dunns patent for gold Dunns patent for gold refiningrefining

AuAu Recovering special matalsRecovering special matals

Such as Sb ,Bi, Sn,Se,Te,InSuch as Sb ,Bi, Sn,Se,Te,In

Days patent for refractory Days patent for refractory ceramic percious metalsceramic percious metals

Pt,PdPt,Pd Platinum and palladiumPlatinum and palladium

Were recovered with ofWere recovered with of

80.3% and 94.2% 80.3% and 94.2% respectivelyrespectively

Aleksandrovichs patent for Aleksandrovichs patent for Recovery of gold Recovery of gold

AuAu Gold were recoveredGold were recovered

A summary of typical A summary of typical pyrometallurgical methodspyrometallurgical methods for recovery of metals from electronic waste for recovery of metals from electronic waste

2525

2626

Advantages pyrometallurgical processingAdvantages pyrometallurgical processing

1.High efficiency recovery precious metals from E-waste1.High efficiency recovery precious metals from E-waste

2.Recovery of energy from PC waste gives an example for 2.Recovery of energy from PC waste gives an example for using of plastic in E-waste using of plastic in E-waste

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Disavantages pyrometallurgicalDisavantages pyrometallurgical processingprocessing

1.Integrated smelters cannot recover1.Integrated smelters cannot recover aluminum andaluminum and iron iron as metalsas metals

2.Ceramic componets and glass in the2.Ceramic componets and glass in the E-waste E-waste increase the amount of slagincrease the amount of slag from Blast furnaces from Blast furnaces

3.Precious metals stay for a 3.Precious metals stay for a long timelong time in in thethe pyrometallurgical processingpyrometallurgical processing

2828

Disavantages pyrometallurgicalDisavantages pyrometallurgical processingprocessing

4.Energy recovery and utilizing of organic constituents as a 4.Energy recovery and utilizing of organic constituents as a reducing agent are reducing agent are only on its beginningonly on its beginning

5.Thermal processing of e-waste provides a feasible approach 5.Thermal processing of e-waste provides a feasible approach for recovery of energy from e-wastefor recovery of energy from e-waste

if if a comprehensive emissiona comprehensive emission control system iscontrol system is installedinstalled

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Recovery of precious metals fromRecovery of precious metals fromE-Waste by hydrometallurgicalE-Waste by hydrometallurgical

processingprocessing

The main steps in hydrometallurgicalThe main steps in hydrometallurgical

Separation and purificationSeparation and purification

Processing consist of a series of acidProcessing consist of a series of acid

Or caustic leaches of solid materialOr caustic leaches of solid materialPrecipitation of impurities

Solvent extraction

Adsorption

Cementation..…

3030

Leaching of precious metalsLeaching of precious metals

Cyanide leachingCyanide leaching

Halide leachingHalide leaching

Thiourea leachingThiourea leaching

Thiosulfate leachingThiosulfate leaching

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Halide leachingHalide leaching

Exceptions of flurine and astatineExceptions of flurine and astatine

Gold forms both Au(I) and Au(III) complexes with all Gold forms both Au(I) and Au(III) complexes with all halogenshalogens

Low pHLow pH

High halogen levelHigh halogen level

Icreased temperatureIcreased temperature

High surface areaHigh surface area

3232

Aqua regiaAqua regia

2HNO2HNO33 + 6HCl 2NO + 4H2O +3Cl + 6HCl 2NO + 4H2O +3Cl22

2Au + 11HCl + 3HNO2Au + 11HCl + 3HNO33 2HAuCl 2HAuCl44 + 3NOCl + 6H2O + 3NOCl + 6H2O

AdvantageAdvantage

The process generally fastThe process generally fast

Low reagent consumptionLow reagent consumption

Halide leachingHalide leaching

disavantagedisavantage

Highly corrosive acidHighly corrosive acid

Highly poisonousHighly poisonous

3333

Recovery of precious metale from leachateRecovery of precious metale from leachate

CementationCementation

Crowe 1890Crowe 1890

Zinc cementationZinc cementation

2Au2Au(CN)(CN)22- - +2e 2Au+4CN+2e 2Au+4CN--

ZnZn+ 4CN+ 4CN-- Zn(CN) Zn(CN)44-2-2 + 2e + 2e

PH 8-11PH 8-11

3434

Crushed matter (0.3 mm)Crushed matter (0.3 mm)

Sulfuric acid leaching of copperSulfuric acid leaching of copper

filtrationfiltrationPrecipitation (NaCl) of AgPrecipitation (NaCl) of Ag

filtrationfiltration Cu RecoveryCu Recovery

AgClAgCl

Chloride leaching of palladiumChloride leaching of palladium

filtrationfiltration

Cyanide leaching of gold and silverCyanide leaching of gold and silver

filtrationfiltration

Solid waste treatmentSolid waste treatment

Cementation ( Al )Cementation ( Al ) filtrationfiltration RecyclingRecycling

Pd,Ag,AuPd,Ag,Au

Activeted Carbon AdsorptionActiveted Carbon Adsorption

Ag,Au,CuAg,Au,Cu

RecyclingRecycling

LL

SS

LL

SS

LL

SS

LL

SS

LL

SS

LL

SS

3535

Comparing withComparing withthe pyrometallurgical processing the pyrometallurgical processing

hydrometallurgical methode ishydrometallurgical methode is

More exactMore exact

More predictableMore predictable

More easily controlledMore easily controlled

3636

Recovery of hazardious metalsRecovery of hazardious metalsfrom E-Wastefrom E-Waste

Cathod Ray TubeCathod Ray Tube CC RR TT

0.50.5 – – 55 kg pbkg pb

3737

Cathode Ray Tube RecyclingCathode Ray Tube Recycling

1.Glass1.GlassFunel glass, panel glass,solder glass,neckFunel glass, panel glass,solder glass,neck

SioSio22,Nao,Cao for coloring and,Nao,Cao for coloring and

Zno,Bao,Pbo for proctecting from X-RaysZno,Bao,Pbo for proctecting from X-Rays

2.Non glass2.Non glassPlastic,steel,copper,electron gun ,phosphor coatingPlastic,steel,copper,electron gun ,phosphor coating

CRT componentsCRT components

3838

Cathode Ray Tube RecyclingCathode Ray Tube Recycling

1.Glass-to-glass recycling1.Glass-to-glass recycling

2.Glass-to-lead recycling2.Glass-to-lead recycling

3939

collectioncollection

sortingsorting

Vibratin scrrenVibratin scrren

Magnetic separationMagnetic separation Ferrous metalsFerrous metals

Eddy current separationEddy current separation Nonferrous metalsNonferrous metals

Glass-to-lead recyclingGlass-to-lead recycling

4040

Eddy currentEddy current

σσ:: electrical conductivityelectrical conductivity

ρρ : : densitydensity

σσ//ρρ :: ratio of electrical conductivity to densityratio of electrical conductivity to density

MaterialsMaterials σσ (10 (10 -8 -8 / / ΏΏ m ) m ) ΡΡ (10 (10 3 3 Kg / m Kg / m 33 ) ) σσ / / ρρ (10 (10 3 3 m m 2 2 / / ΏΏ kg ) kg )

AlAl 0.350.35 2.72.7 13.113.1

ZnZn 0.170.17 7.17.1 2.42.4

AgAg 0.630.63 10.510.5 66

CuCu 0.590.59 8.98.9 6.66.6

BrassBrass 0.140.14 8.58.5 1.71.7

PbPb 0.050.05 11.311.3 0.40.4

H.-Y. Kang, J.M. Schoenung / Resources, Conservation and Recycling 45 (2005) 368–400

4141

pretreatmentpretreatment

reverberatory reverberatory furnacefurnace

reductantreductant

slageslage disposaldisposal

landfillsdlandfillsdSoft PbSoft Pb

99.98%99.98%

H.-Y. Kang, J.M. Schoenung / Resources, Conservation and Recycling 45 (2005) 368–400

PbO + C → Pb + CO

4242

ConclusionConclusion

1.Recycling of electronic waste is an important subject1.Recycling of electronic waste is an important subject

2. E-Waste is a huge secondary resource (maine above ground) 2. E-Waste is a huge secondary resource (maine above ground)

Shouh not wastedShouh not wasted

3.The major economic driver for recycling of electronic waste3.The major economic driver for recycling of electronic waste

is from the recovery of precious metalsis from the recovery of precious metals

4343

ReferencesReferences J.Cui,E.Fotssberg,Mechanical recycling of waste electronic and electric equipment J.Cui,E.Fotssberg,Mechanical recycling of waste electronic and electric equipment : a reveiew , j.Hazard .mater.99 (3) (2003) 243-263: a reveiew , j.Hazard .mater.99 (3) (2003) 243-263EPCEU,:Directive 2002 / 96/EC of the European parliament and of the council of 27EPCEU,:Directive 2002 / 96/EC of the European parliament and of the council of 27January 2003 on waste electronic and electrical equipment (WEEE) ,off.j.Eur.UnionJanuary 2003 on waste electronic and electrical equipment (WEEE) ,off.j.Eur.Union(2003) 24-38(2003) 24-38T. Maruyama, H. Matsushita, Y. Shimada, et al., Proteins and protein-rich biomass as environmentally friendly adsorbents selective for precious metal ions, Environ. Sci.

Technol. 41 (4) (2007) 1359–1364, Feb 15A.N. Mabbett, D. Sanyahumbi, P. Yong, et al., Biorecovered precious metals from

industrial wastes: Single-step conversion of a mixed metal liquid waste to a bioinorganic catalyst with environmental application, Environ. Sci. Technol. 40 (3) (2006) 1015–1021, Feb 1

J. Shibata, S. Matsumoto, Development of Environmentally Friendly Leaching and Recovery Process of Gold and Silver from Wasted Electronic Parts, 2007-10-29, 2007D. Morin, A. Lips, T. Pinches, et al., BioMinE – Integrated project for the development

of biotechnology for metal-bearing materials in Europe, Hydrometallurgy 83 (1–4) (2006) 69–76.