Extractive Metallurgy Study Guide Assessment

1 .2Y ou rT hou gh ts .Usinganymeansyouarecomfortablewithandusingyourownwords,answerthefollowingquestions:1.Definethefollowingterms:a.Hydrometallur gyHydrometallur gyisatypeofextractivemetallur gythatdealswithaqueousorinor ganicsolutionsthattreatoresbydissolution,similartonaturalleachingprocesses.b.Pyrometallur gyPyrometallur gyisatypeofextractivemetallur gythatdealswithhightemperaturesthattreatoresbyheattoextractandpurifymetals.c.Electrometallur gyElectrometallur gyisatypeofextractivemetallur gythatdealswithelectricalener gythattreatsoresbyelectrolyticprocessestoextractandrefinemetals.2.Findadditionalresourcesonatleastoneextractionmethodforgold,nickelandcopperandbrieflydescribethemethod.OneextractionmethodforgoldistheAmalgamProcess[1],consideredtheoldesttechnicalmethod.Thismethodusesmercurywhereinitisaddedtothecrushedorecontaininggoldleadingthegoldtojointhesurfaceofthemercury .Thisthenformsasilveryshiningalloysolution,amalgam,andisheateduntilthemercuryevaporates,leavingthepurerawgold.However ,thisisadangeroussetupfortheenvironmentandforthehealthofthepeopleinvolvedduetothepresenceofhighlypoisonousmercury .OneextractionmethodfornickelistheMondprocess[2].Inthisprocess,nickeliscombinedwithcarbonmonoxideinthepresenceofasulfurcatalysttogeneratenickelcarbonyl.W iththat,therearetwomethodsforrecoveringthenickel.Onemethodissendingitthroughahugechamberathightemperaturescontainingtensofthousandsofnickelspheresthatarecontinuallyagitated;afterward,itsubsequentlydecomposes,leavingjustpurenickelonthenickelspheres.Ontheotherhand,anothermethodwouldbedegradingnickelcarbonyltofinenickelpowderinasmallerchamber .OneextractionmethodforcopperisHeapLeaching[3].Duringthisprocedure,thecrushedcopperoreisstackedinaheapontopofanimpermeablelayerandonalittleincline.Afterward,itisthensubsequentlydispersedbythesulfuricacidasitpoursdownwardfromthetopoftheheappilethroughsprinklers.Theresultantcoppersulfateandsulfuricacidpregnantleachsolutionisthencollectedinasmallpool.2 .2Y ou rT hou gh ts .Usinganymeansyouarecomfortablewithandusingyourownwords,answerthefollowingquestions:1.DefineRoastingasitisusedinhydrometallur gy.Howdoesitenabletherecoveryofmetalsfromhighgradeconcentrates?Giveatleastoneexample.Roastingisdescribedastheheatingoftheoreorconcentratewithexcessairtoconvertthemintoanotherform.Itenablestherecoveryofmetalsfromhighconcentratesbychangingtheirstructureorcomposition,leadingthemtoeasierdissolutioninaqueousorinor ganicsolutions.Anexampleofthiswouldbecopper -cobaltores,whereas,undercarefullyregulatedcircumstances,thesulfideconcentrateisroastedtoconvertthemajorityofthecobaltsulfidetoasolublesulfatewhilereducingtheconversionofthecopperandirontotheirwater -solubleforms.[4].2.Leachinga.Determineatleasttwoofthemostcommonleachingagentsusedforgold,copper ,andnickel.Forgold,themostcommonleachingagentusediscyanidesodiumcyanide(NaCN)whichhasbeenusedworldwidesinceitisaf fordableandef ficient;however ,ithasdif ficultiesandhazardsworkingwithit[5].W iththat,varioussaferalternativeswererecommendedtobeused,suchassodiumthiosulphate(Na S O )[6].Ontheotherhand,themostcommonleachingagentsusedforcopperissulfuricacid-ferricsulfateandsulfuricacid(H SO )[7]sinceitdissolvesquickerwiththisreagent;theusageofitcanbeobservedinheapleachingorelectro-refiningofcopper .Similartocopper ,themostcommonleachingagentusedfornickelisalsosulfuricacid(H SO )whichisobservedinmoabayprocessorhighpressureacidleachingofnickel.Moreover ,ammonia(NH )isalsoacommonleachingagentused,especiallyinSherrittGordonProcess.b.Arrangethedif ferentleachingmethodsaccordingtothelengthoftimeneededforittoachievemetalrecovery .Leachingmethodsarrangedfromshortesttolongesttimeperiodneededtoachievemetalrecovery:-AgitationLeaching(2-48hours)-PressureLeaching(5hours)-V atLeaching(10days)-HeapLeaching(6months)-DumpLeachingandInsituLeaching(20years)c.Dif ferentiatethefollowingandjustifywhichonewillleachmetalfaster .i.DumpleachingvsheapleachingInaleachingprocessknownas"dumpleaching,"oreextractedstraightfromthemineisdumpedinopenpitminesandsprayedwiththelixiviantatthetopofthedump,producingpregnantsolutionorleachateatthebottom.Ontheotherhand,heapleachingismoresystemicsincetheoresextractedarealreadysize-reducedandnotjustdumpedbutarestructuredinslightlytiltedheaps.Thelixiviantisthenpouredonthetopandflowstothebottom,wherethepregnantsolutionorleachateiscollected.ii.AgitationleachingvsPressureleachingAgitationleachingisaleachingprocessinwhichtheparticlesinsidethetankareagitatedtopreventsedimentation.Pressureleaching,ontheotherhand,isaleachingprocedurethatuseshightemperaturesandpressures.Furthermore,agitationleachingisutilizedforparticleswithadiameteroflessthan0.5mm,whereaspressureleachingisusedformineralsthataredif ficulttodissolveunderatmosphericpressure.3.SolutionPurificationandConcentrationa.Definethefollowingi.ResinResinisessentiallyalong-chainpolymerwithelectricallychar gedsiteswhereoneionmaytaketheplaceofanother .Whenionexchangehappens,itisarrangedinverticalcolumnstoprovidealar geareaofcontactwiththepregnantsolution.ii.EluantEluantisthetermforthesolventusedintheelutionprocessofionexchangetocleantheresinandcollecttheionsthatareattachedtoit.iii.EluateEluateistheproducedsolutionfromtheelutionprocess,whichcontainstheionsthatwerecollected.iv .ActivatedCarbonActivatedcarbonisatypeofcarbonthathasbeentreatedtohavetiny ,low-volumeholes,increasingtheamountofsurfaceareathatisaccessibleandsuitableforreactionslikeadsorption.v .PregnantSolutionPregnantsolutionisdefinedasthesolutiongeneratedwhenpreciousmetalisleachedfromanoreorconcentratetoasolutionbydissolution.vi.EnrichedSolutionEnrichedsolutionisreferredtoasthesolutionthathasaconcentratedquantityofthedesiredpreciousmetal.vii.BarrenSolutionBarrensolutionisdescribedasthesolutionfromwhichthedesiredvaluablemetalhasbeenextracted.viii.StrippingStrippingisdefinedastheprocessofrecoveringthetar getmaterialinanenhancedandconcentratedformfromtheor ganicsolventsothatitmaybereusedintheextractionprocess[8].b.WhatmakesActivatedCarbonanidealadsorbent?ActivatedCarbonisanidealadsorbentmainlybecauseithasavastsurfacearea,increasingitsabilitytocapturemolecularsubstances.Moreover ,italsohashighporosity ,isaf fordable,andiswidelyaccessible.[9].c.Dif ferentiateCIPandCIL.TheprimarydistinctionbetweenCarbon-in-Pulp(CIP)andCarbon-in-Leach(CIL)isthatinCIP ,leachingandadsorptionoccurindif ferentseparatetanks,whereasinCIL,leachingandadsorptionoccurinthesametanks.4.MetalSeparationandRecoverya.Whyisprecipitationnotanelectrometallur gicalprocess?Precipitationisnotincludedintheelectrometallur gicalprocess,butratherinhydrometallur gicalprocess3 .2Y ou rT hou gh ts .Usinganymeansyouarecomfortablewithandusingyourownwords,answerthefollowingquestions:1.Dif ferentiateCrystallizationandPrecipitation.(Note:don tjustgivethedefinitionofeach)Crystallizationandprecipitationaimtoformasolidfromaliquidbutwithdif ferentprocesses.Incrystallization,itadjuststhesolubilityofthesoluteinasolventandaltersotherparameterssuchastemperatureandPHsothatcrystallizedmetalwillformoutofthesolution.Ontheotherhand,precipitationoccursthroughchemicalreactionsfromdilutionoradditionofreagentstothesolutionproducingaprecipitate.Furthermore,crystallizationismoreef fectiveinformingpuremetalsratherthanprecipitationformingcompounds.2.Inredoxreactions,reductioninvolvesthegainingofelectronsandoccursatthecathode.Meanwhile,oxidationinvolvesthelosingofelectronsandoccursattheanode.Givetwochemicalreactionsthatdemonstrateeachtypeofreaction.ReductionReactionPb +2e Pb(s)OxidationReaction2Cl Cl (g)+2e 3.Dif ferentiateElectrowinningfromElectrorefining.Whatisthedif ferenceintheanodesandcathodesusedforeachprocess?Whichwillgiveapurerproduct?Electrowinninguseselectrolysistoachieveacathodicreactionfromanelectrolytetoasolidmetal;italsousesaninsolubleanode.Whentheinsolubleanodeandcathodeareimmersedintheelectrolyte(enrichedpregnantsolution),andelectricityisapplied,themetalisreducedtopuremetalandthendepositedinthecathode,whileintheanode,dustisgenerated.Ontheotherhand,electrorefininghastworeactions:metaldissolutionandmetaldeposition.Unlikeelectrowinning,italsousesasolubleanodecomposedofmetaltobepurified.Sometimes,thecathodeproductofelectrowinningisthefeedanodeofelectrorefining.Byelectricity ,themetalintheanodewilldissolveintheelectrolyteandbedepositedintothecathode;thisprocessensuresthatonlythedesiredmetalwilldissolveanddeposit,producinghigherpuritythantheelectrowinning.4.Drawanelectrochemicalcellandgiveabriefdescriptionforeachcomponent.Anode-thecompartmentwhereoxidation,losingofelectrons,occursCathode-thecompartmentwherereduction,gainingofelectrons,occursElectrolyte-thesolutioninwhichtheanodeandcathodeisimmersedandallowsionstomoveSaltbridge-enablestheback-and-forthmovementofionstopreventchar geaccumulationV oltmeter-anexternalchannelthatpermitselectronpassageandmeasurestheelectrochemicalcell'spotentialorvoltage5.CalculatetheEcellcontainingofanelectrochemicalcellcontainingZincandCopperions.W illdissolvedcopperdepositinzincmetal?Orviceversa?Zn(s)+Cu (aq)Zn (aq)+Cu(s)HalfCells:Zn(s)Zn (aq)+2e E =+0.763Cu (aq)+2e Cu(s)E =+0.340E cell=E reduction,cathode+E oxidation,anodeE cell=+0.340+(-0.763)E cell=+1.103VSinceallthatishappeningisthemovementofelectronsonmetalatoms,noreactionwilltakeplace(directredoxreaction).6.Calculatetheelectrodepotential,GibbsFreeener gyforthesystemdescribedaboveusingtheNernstEquation.E=E -ln [(�)�(�)�(�)�(�)�(Assumingthattheelectrodepotentialisthesameasstandardcellpotential.)E=E E=+1.103VG=-nFEcellG=-(2)(96500)(1.103)G=-212879kJ4 .2Y ou rT hou gh ts .Usinganymeansyouarecomfortablewithandusingyourownwords,answerthefollowingquestions:1.Definethefollowingterms:a.Refractory(Giveexamplesofeach)Refractoryisdescribedasanon-metallicheat-resistantmaterialthatisusuallyusedasliningsforequipmentsuchasfurnacesandboilers.Itpermitsheatretention,allowingchemicalprocessestocontinueandoptimizingprocessef ficiency .Therearemanytypesofrefractories,includingacidrefractories,basicrefractories,andneutralrefractories[10].Acidrefractoriesaremadeofacidicmaterialslikesilica(SiO )andalumina(Al O ).Basicrefractories,ontheotherhand,suchasdolomite(CaMg(CO ) ),arematerialsthatarealkalinestablebutdonotreactwithacids.Neutralrefractories,suchaschromiumoxide(Cr O ),areutilizedinsettingswheretheslagandatmosphereareeitherbasicoracidic.b.Coal(listdownthedif ferenttypes)Coalisdescribedasasedimentaryrockmadeupmostlyofsolidor ganiccomponentssuchasplantsandvegetalmatterthathasbeensubjectedtothelong-termactionofgeologicprocessesandcircumstances.Moreover ,itisconsideredasthemetallur gicalindustry'smostsignificantsourceofener gy.Infact,inthePhilippinesin2021,coalcontributedthemosttoelectricitygeneration,accountingforover58%[1 1].Inaddition,coalistypicallynotburntdirectlybutrathertransformedtootherproducts.c.CokeCokeisaformofhydrocarbonfuelthatischaracterizedasasolidsecondaryfuel.Itisacoalderivativeproducedeitherfromthepyrolysisprocess,inwhichcoalisburntintheabsenceofair ,orfromthecoherentcellularremnantofbituminouscoal.2.WhichfueltypeisusuallyusedinPyrometallur gicalprocesses?Why?ThefueltypethatisusuallyusedinPyrometallur gicalprocessesarethesolidfuels,particularlycoal,sincetheyareaf fordableandhaveanicebalanceofphysicalandchemicalqualities.3.Dif ferentiatecalcinationandroasting.Calcinationandroastingarepartofthepretreatmentprocessofpyrometallur gy,inwhichoreistransformedintoamorereducibleform;however ,theyhavedif ferentapproaches.Calcinationistheprocessofheatinganorewithoutthepresenceofair ,whichresultsinthetransformationofcarbonatesintooxides.Ontheotherhand,roastingistheprocessofheatinganorewhileaddingmoreair ,whichcausessulfidestochangeintooxidesorsulfates.4.DescribehowConvertingisconducted.Convertingreferstotheprocessofrefiningandpurifyingmetalafterithasbeensmeltedwhichissimilartowhenelectrorefiningisdoneafterelectrowinning.5.Inwhichphasecanyoumostlikelyexpectyourvaluablemetaltooccur?Basedonmyunderstanding,themattephase,whereintheprimarymetalbeingextractedisrecoveredbeforeafinalreductionprocess[12],istheoneinwhichthepreciousmetalismostlikelytooccur .6.Pickonetypeoffurnaceandlabelthepartsinwhichdif ferenttypesofheattransferoccur .CrucibleFurnace[13]Theredlinesdepictradiation,whichisthetransferofheataswaves,rays,orparticlesmovinginavacuum.Thevioletlinesrepresentconvectionwhichinvolvesthemovementofliquidsandgasestotransferheat.Theorangelinesshowconduction,amethodofheattransmissioninwhichnoparticlesaremoved.Sources:[1]GoldExtraction/Mining.Gold.info.(n.d.).RetrievedNovember25,2022,fromhttps://www .gold.info/en/gold-extraction-mining/[2]Nickel:smelting.Metalpedia.(n.d.).RetrievedNovember25,2022,fromhttp://metalpedia.asianmetal.com/metal/nickel/extraction.shtml[3]CopperMiningandPr ocessing:Pr ocessingCopperOr es.SuperfundResearchCenter .(n.d.).RetrievedNovember25,2022,fromhttps://superfund.arizona.edu/resources/learning-modules-english/copper -mining-and-processing/processing-copper -ores#:~:text=Copper%20mining%20is%20usually%20performed,blast%20and%20break%20the%20rock.[4]T aylor ,J.C.(n.d.).Cobaltpr ocessing.EncyclopediaBritannica.RetrievedNovember25,2022,fromhttps://www .britannica.com/technology/cobalt-processing[5]NevadaDivisionofEnvironmentalProtection.(2018,July27).F AQs-BasicMiningandPr ocessingPrinciples.RetrievedNovember25,2022,fromhttps://ndep.nv .gov/uploads/land-mining-faq-docs/20180727_F AQ_Mining_Processing_ADA.pdf[6]Cyanide-fr eegoldr ecovery.CSIRO.(n.d.).RetrievedNovember25,2022,fromhttps://www .csiro.au/en/work-with-us/industries/mining-resources/processing/going-for -gold[7]Johnson,P .H.,&Bhappu,R.B.(n.d.).Chemicalmining--Astudyofleachingagents.NewMexicoBureauofGeology&MineralResources.RetrievedNovember25,2022,fromhttps://geoinfo.nmt.edu/publications/monographs/circulars/downloads/99/Circular -99.pdf[8]Michaud,D.(2017,January31).SolventExtractionPr ocessSX:Hydr ometallur gicalExtractionofCopper.91 1Metallur gist.RetrievedNovember25,2022,fromhttps://www .911metallur gist.com/solvent-extraction/[9]Nowicki,H.(2016,February1).Thebasicsofactivatedcarbonadsorption.W aterT echnology .RetrievedNovember25,2022,fromhttps://www .watertechonline.com/wastewater/article/15549902/the-basics-of-activated-carbon-adsorption[10]Romq,P .(2018,June28).T ypesofr efractories.SlideShare.RetrievedNovember25,2022,fromhttps://www .slideshare.net/PatelRomq/types-of-refractories[1 1]Coal.DepartmentofEner gy.(n.d.).RetrievedNovember25,2022,fromhttps://www .doe.gov.ph/coal-overview[12]Matte(metallur gy).chemeurope.com.(n.d.).RetrievedNovember25,2022,fromhttps://www .chemeurope.com/en/encyclopedia/Matte_%28metallur gy%29.html[13]Zafar ghandi,M.S.(2018,November8).Howcouldincr easeefficiencyofcruciblefurnace?ResearchGate.RetrievedNovember25,2022,fromhttps://www .researchgate.net/post/how_could_increase_ef ficiency_of_crucible_furnace