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Study of Integrated Leaching and Electrowinning of Copper From

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Study of Integrated Leaching and Electrowinning of Copper From A STUDSTUDYY OOFF INTEGRATEINTEGRATEDD LEACHINLEACHINGG ANANDD ELECTROWINNINGELECTROWINNING OOFF COPPECOPPERR FROFROMM CHALCOPYRITCHALCOPYRITEE OREORE USINUSINGG CHLORIDCHLORIDEE MEDIAMEDIA bbyy PrashanPrashantt KumaKumarr SarswatSarswat A thesithesiss submittedsubmitted toto ththee facultyfaculty ofof ThThee UniversitUniversityy ofof UtahUtah iinn partiapartiall fulfillmenfulfillmentt ofof ththee requirementrequirementss foforr ththee degredegreee ofof MasterMaster ofof ScienceScience DepartmentDepartment ofof MetallurgicalMetallurgical EngineeringEngineering TheThe UniversityUniversity ofof UtahUtah MayMay 20102010 CopyrighCopyrightt © PrashanPrashantt KumaKumarr SarswaSarswatt 20102010 AlAlll RightRightss ReservedReserved THE UNIVERSITY OF UTAH GRADUATE SCHOOL SUPERVISORY COMMITTEE APPROVAL of a thesis submitted by Prashant Kumar Sarswat This thesis has been read by each member of the following supervisory conunittee and by majority vote has been found to be satisfactory. z reb w{O Sivaraman Guruswamy � THE UNIVERSITY OF UTAH GRADUATE SCHOOL FINAL READING APPROVAL To the Graduate Council of the University of Utah: Date Mi ael L. Free C air: Supervisory Committee Approved for the Major Department Jan D. Miller Chair Approved for the Graduate Council arles MWight Dean of The Graduate School ABSTRACT Hydrometallurgical recovery of copper from chalcopyrite ore using chloride media has several advantages over sulfate based processes: faster kinetics; high solubility of metals; easy oxidation of sulfides; reduced energy consumption step due to utilization of one electron per atom of copper formation, rather than two in most electrowinning operations; and conversion from water hydrolysis to ferric ferrous half-cell reaction, which reduces cell voltage. Disadvantages include corrosivity and reduced limiting current density during electrowinning. A comparison of advantages and disadvantages indicates that leaching of sulfide ore or concentrate in chloride media may be advantageous. Several chloride media have been examined for copper extraction. Cupric chloride and ferric chloride solutions have already proven to be efficient leaching agents; ferrous chloride has been utilized for copper production by means of the Hunt and Douglas process. Cupric/cuprous ion ratio plays a vital role for leaching kinetics. Individually, ferric and cupric ions have proven to be good leaching agents; a combination of ferric/ferrous and cupric/cuprous ions has been explored in this research by conducting factorial design of experiments. Simultaneous leaching and clectrowinning is explored in this study as a way to reduce processing and energy costs. Electrowinning has been performed using a solution similar to that being utilized for leaching; factorial design experiments were also conducted to study various factors which affect electrowinning. 3 2 2 In summary, this study is focused on determining the effects of Fe +, Fe +, Cu +, Cu+ and acid concentration on leaching of chalcopyrite as well as the electrowinning of copper from the ---------------- -- resultinresultingg leachingleaching solutionsolution usinusingg a chloridechloride mediummedium.. A lablab scalescale designdesign ooff experimentsexperiments forfor integrateintegratedd leachinleachingg anandd electrowinninelectrowinningg ooff coppecopperr fromfrom ororee iiss discusseddiscussed.. PossiblePossible variationvariationss ofof experimentalexperimental parameterparameterss ttoo improveimprove performancperformancee araree alsalsoo discusseddiscussed.. ResultResultss showeshowedd thathatt highhigh hydrochlorihydrochloricc acidacid andand cupriccupric ioionn concentratioconcentrationn assisteassistedd leachingleaching;; oonn ththee otheotherr hand, electrowinningelectrowinning ofof coppecopperr frofromm chalcopyritechalcopyrite ororee leachinleachingg solutionsolution usinusingg chloridchloridee medimediaa iiss muchmuch feasiblefeasible whewhenn aciacidd anandd cupricupricc ioionn concentrationconcentrationss areare lowlow (0.0(0.055 M/Mill anandd 0.00.011 MM/lil,, respectively).respectively). v TABLTABLEE OOFF CONTENTSCONTENTS ABSTRACABSTRACTT ............................................................................................................................ .iviv LISLISTT OOFF TABLETABLESS .................................................................................................................. viiviiii ACKNOWLEDGEMENTACKNOWLEDGEMENTSS .................................................................................................... .ixix ChapteChapterr 11.. INTRODUCTIOINTRODUCTIONN .................................................................................................. 1 1.11.1 OvervieOvervieww ooff fundamentafundamentall ooff metametall leachinleachingg .. " ........................................... 1 1.21.2 OvervieOvervieww ooff fundamentafundamentall ooff metametall electrowinninelectrowinningg ...................................... 2 1.31.3 OvervieOvervieww ooff conventionaconventionall chalcopyritchalcopyritee processinprocessingg ...................................... 6 1.41.4 OvervieOvervieww ooff sulfidsulfidee basebasedd anandd chloridchloridee basebasedd mediamedia foforr coppecopperr electrowinningelectrowinning ................................................................... 8 1.51.5 OverviewOverview oofleachingf leaching ofof chalcopyritchalcopyritee oreore witwithh ususee ofof ironiron chloridechloridess andand coppercopper chloridechloridess ....................................................... 1010 2.2. EXPERIMENTAEXPERIMENTALL PROCEDUREPROCEDURESS .................................................................................. 1212 2.12.1 ListList ofof chemicalschemicals usedused ........................................................................ 1212 2.22.2 LeachantLeachant compositioncomposition ........................................................... '" .......... 1313 2.32.3 ElectrochemicalElectrochemical cellcell andand instrumentationinstrumentation ................................................ 1313 2.42.4 ExperimentalExperimental proceduresprocedures .................................................................... .1414 2.4.12.4.1 ColumnColumn leachingleaching experimentsexperiments withwith electrowinningelectrowinning ............................ .1414 2.4.22.4.2 FactorialFactorial designdesign columncolumn leachingleaching experimentsexperiments ................................ .1616 2.4.32.4.3 FactorialFactorial designdesign electrowinningelectrowinning experimentsexperiments .................................. 2020 2.4.42.4.4 ElectrowinningElectrowinning testtest matrixmatrix II.II ..................................................... 2222 2.4.52.4.5 ImageImage analysisanalysis ..................................................................... .2424 2.52.5 DetailedDetailed leachingleaching kineticskinetics evaluationevaluation ..................................................... 2424 3.3. RESULTSRESULTS ANDAND DISCUSSIONDISCUSSION ....................................................... '" ........ 2727 3.13.1 EvaluationEvaluation ofof primaryprimary combinedcombined leachingleaching andand electrowinningelectrowinning experimentsexperiments ....... 2727 3.1.13.1.1 ConsumptionConsumption ofof acidacid ..............................................................29 29 3.1.23.1.2 ConcentrationConcentration ofof coppercopper andand ironiron (ICPMS(ICPMS analysis)analysis) ......................... 3030 3.1.33.1.3 RecoveryRecovery ofof coppercopper byby electrowinningelectrowinning ..................................................... 3030 3.23.2 AnalysisAnalysis ofof factorialfactorial designdesign columncolumn leachingleaching experimentsexperiments ........................... 3333 3.3.33 AnalysiAnalysiss ooff leachin leachingg experimentexperimentss ... ....... ..... ......................... .......... .... ..... .4040 3.3.3.3.11 ModeModell 11:: sphericasphericall particlparticlee undeunderr reactioreactionn controcontrol..l .. .... ............................ .4242 3.3.3.3.22 ModeModell 22:: sphericasphericall particlparticlee undeunderr producproductt layelayerr controcontrol..l .......................... .4343 3.3.44 AnalysiAnalysiss ooff factoriafactoriall desigdesignn electrowinninelectrowinningg experimentexperimentss ................................. .4646 3.4.3.4.11 ComparisoComparisonn ooff currencurrentt efficiencefficiencyy (experimenta(experimentall anandd simulatedsimulated)) ... ........ .4646 3.4.3.4.22 AnalysiAnalysiss ooff electroplateelectroplatedd samplsamplee .. ... ....... ....... ... .... .. ..... ............... ..662 2 3.4.3.4.33 FactoriaFactoriall desigdesignn analysianalysiss ooff experimentexperimentss .. ............... ............ .... ..... .. 6655 3.3.55 AnalysiAnalysiss ooff electrowinninelectro winningg testestt matrimatrixx IIII ........ ........... ... ..... ... ............ .. ..... 6699 44.. CONCLUSIONCONCLUSIONSS ..... ..... ....... ............ ........ ... ... ......... .. .. ........ ...... ............ .... 7733 AppendiceAppendicess AA.. IMAGEIMAGESS OOFF ELECTROPLATEELECTROPLATEDD SAMPLESAMPLESS ....... .. ..................... ...... .. ..... ......757 5 BB.. CONCENTRATIOCONCENTRATIONN OOFF IONIIONICC SPECIESPECIESS ........ .............. ... .. .... .... ..... .............78 78 CC.. EXPERIMENTAEXPERIMENTALL ANANDD SIMULATESIMULATEDD CURRENCURRENTT DENSITYDENSITY ANANDD CURRENCURRENTT POTENTIAPOTENTIALL RELATIONSHIRELATIONSHIPP FOFORR DIFFERENDIFFERENTT
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