Molybdenum - techintroduce

Introduction

Molybdenumisametalelementdiscoveredrelativelylate.ItwasonlyextractedfrommolybdenitebySwedishchemistsin1792.Becausemetalmolybdenumhastheadvantagesofhighstrength,highmeltingpoint,corrosionresistance,andwearresistance,ithasbeenwidelyusedinindustry.

Inthemetallurgicalindustry,molybdenumisusedasanadditiveintheproductionofvariousalloysteels,oritcanbecombinedwithtungsten,nickel,cobalt,zirconium,titanium,vanadium,rheniumandotheradvancedalloystoimproveitshigh-temperaturestrengthandwearresistance.Resistanceandcorrosionresistance.Molybdenum-containingalloysteelisusedtomanufacturetransportationdevices,locomotives,industrialmachinery,andvariousinstruments.Certainstainlesssteelscontaining4%to5%ofmolybdenumareusedtoproduceprecisionchemicalinstrumentsandequipmentusedinseawaterenvironments.High-speedsteelcontaining4%to9.5%canbeusedtomanufacturehigh-speedcuttingtools.Molybdenum,nickel,andchromiumalloysareusedtomanufacturemetalcomponentsofaircraft,andcorrosion-resistantpartsonlocomotivesandautomobiles.Molybdenum,tungsten,chromium,andvanadiumalloysareusedtomakealloycomponentsandpartsforwarships,tanks,guns,rockets,andsatellites.

Molybdenummetaliswidelyusedasheatingmaterialsandstructuralmaterialsforhigh-temperatureelectricfurnaces,largeelectrodesandgridsofvacuumtubes,semiconductorsandelectriclightsourcematerials.Becauseofitssmallthermalneutroncapturecross-sectionandhighdurability,molybdenumcanalsobeusedasastructuralmaterialfornuclearreactors.

Inthechemicalindustry,molybdenumismainlyusedforlubricants,catalystsandpigments.Duetoitslamellarcrystalstructureandsurfacechemicalproperties,molybdenumdisulfidehasgoodlubricatingpropertiesunderhightemperatureandpressure,andiswidelyusedasanadditiveforoilsandgreases.Molybdenumisacatalystcomponentinthedesulfurizationofhydrogenproductionandotherpetroleumrefiningprocesses.Itisusedintheoxidation-reductionreactionofethanol,formaldehydeandoil-basedchemicals.Molybdenumorangeisanimportantpigment.Molybdenumchemicalsarewidelyusedindyes,inks,colorprecipitationdyes,andanticorrosiveprimers.

Molybdenumcompoundsarealsowidelyusedinagriculturalfertilizers.

Characteristicsofmolybdenumdeposits

Molybdenumisatransitionaliron-philicelementinthegeochemicalclassification.Ininternalmineralization,molybdenumismainlycombinedwithsulfurtoformmolybdenite.Othercommonmolybdenum-containingmineralsincludeironmolybdenum,calciummolybdate(CaMo),colormolybdenumlead(PbMo),collosulfidemolybdenum(

),bluemolybdenum(·nH2O),etc.

Molybdenite()isthemostwidelydistributedmolybdenummineralwithpracticalindustrialvalueamongmorethan30molybdenum-containingmineralsknowninnature.Molybdeniteislead-grey,similartographite,withmetallicluster,andbelongstothehexagonalcrystalsystem.Thecrystalsareoftenhexagonalflakes,withpatternsonthebottom,softandslippery,thinandflexible.Thespecificgravityis4.7～4.8,thehardnessis1～1.5,themeltingpointis795℃,thestreaksontheceramicplatearelightgreengrayorlightgreenblack.Whenheatedto400～500℃

Itiseasytooxidizeandform.Bothnitricacidandaquaregiacandecomposemolybdenite().Molybdeniteisusedintheproductionofferromolybdenumalloys,metallicmolybdenum,calciummolybdate,ammoniummolybdate,lubricants,etc.

Morphologicalcharacteristics

Therearepolytypesinmolybdenite.Experimentsshowthattheappearanceofpolytypesisrelatedtotheformationtemperature.Theformationtemperatureof2H-typemolybdeniteishigherthanthatof3R-type.Molybdenite.Amorphous→colloid→3Mo→2HMoisformedfromlowtemperaturetohightemperature.Thetemperaturemeasurementdatashowsthattheformationtemperatureofmolybdenitehasawiderange,fromafairlyhightemperaturetoarelativelylowtemperature,andalargeamountofitisformedinthehightomediumtemperaturestage.Undertheactionofhydrothermalfluid,precipitatesunderacidicconditions,thatis,molybdeniteismoststableunderacidicconditions.Whenthesolutionturnstoneutral,molybdenumbecomessolublethiomolybdateandMolybdateisactiveagain.Underlowandnormaltemperatureconditions,generatescolloidalthiomolybdenite()inastrongacidreductionenvironment,andtheproductofitsoxidationisbluemolybdenum(section>·n).Inexogenouseffects,molybdenumisandhasstrongmobility.Similartouranium,itisstableinthetransitionalenvironmentofoxidationandreductionthatisclosetoneutraloralkalescent,therebygeneratingavarietyofuranium-containingmolybdateminerals,suchasmolybdenite,molybdenite,etc.Iron-molybdenumbloomisacommonmineralformedbysulfideoreunderacidicconditions(pH=3～5).Colormolybdenumleadoreistheproductoflead-zincorecontainingmolybdenumunderneutralconditions.

Theionicradiusofrheniumissimilartothatofmolybdenum,soitoftenreplacesmolybdenumandisenrichedinmolybdenite,becomingthemainsourceofindustrialrhenium.Therheniumcontentinmolybdeniteisoftenrelatedtothe3Rtypecontentinmolybdeniteandtherheniumcontentintheore-formingsolution.

Maincomponents

Qualityspecificationsandchemicalcomposition

AccordingtothetechnicalconditionsofGB3200—89molybdenumconcentrate,therearethreeNinevarietiesofgradesQualitySpecificationsofMolybdenumConcentrates

Classes	Types	Molybdenum%isnotlessthan	Impurities%,notmorethan
SiO2	As	Sn	P	Cu	Pb	Cao
Superiorproducts	Firstclass	51	7.0	0.05	0.04	0.03	0.2	0.30	2.8
Class2	51	8.5	0.03	0.02	0.02	0.2	0.15	1.4
Threecategories	51	5.0	0.10	0.10	0.05	0.5	0.60	1.5
Firstclassproduct	Firstclass	47	9.0	0.07	0.07	0.05	0.3	0.40	3.0
Class2	47	11.0	0.05	0.05	0.03	0.3	0.20	2.0
Threetypes	47	6.0	0.20	0.15	0.10	1.0	1.50	1.5
TwoGradeproduct	Firstclass	45	12.0	0.07	0.07	0.07	0.3	0.50	3.0
Class2	45	13.0	0.06	0.06	0.04	0.3	0.30	2.0
Threetypes	45	6.0	0.25	0.15	0.15	1.5	1.50	2.0

Assaytechnology

Molybdenummineralassay:gravimetricmethod,volumetricmethod,colorimetry,polarography,atomicabsorptionspectrophotometry,X-rayspectroscopyandspectroscopyareavailableforthedeterminationofmolybdenumWait.Sincethecontentofmolybdenumintheoreisgenerallylow,colorimetricmethodsareoftenusedfordetermination,andcatalyticpolarographyisalsoused.Themostwidelyusedisthethiocyanatecolorimetricmethod,thatis,molybdenum(VI)isreducedtomolybdenum(V)inanacidsolution,andthemolybdenum(V)formsanorange-redcomplexwiththiocyanateforcolorcomparison.Itcanbereducedinnitricacidorsulfuricacidsolutionwithcorrespondingweakreducingagentssuchasstannouschlorideandthiourea.Thismethodissimple,rapid,withfewinterferenceelements,goodstabilityandhighaccuracy.Differentialspectrophotometrycanbeusedforhighercontentofmolybdenum,andthetraceamountofmolybdenumcanalsobeextractedwithethylacetateforcolorimetry.

Determinationofhighcontentmolybdenum(molybdenumconcentrate),canusegravimetricmethodandvolumetricmethod.Thegravimetricmethodincludesleadmolybdatemethod,benzoinoximemethodand8-hydroxyquinolinemethod.Amongthem,theleadmolybdatemethodhasmanyinterferenceelementsandcomplicatedprocedures,buttheacidityrangeduringprecipitationiswide,andtheleadmolybdatecompositionisstable,sotheaccuracyishigh,anditiswidelyusedinproduction.Thebenzoinoximemethodhasfewerinterferenceelements,butthecompositionoftheprecipitatedleadisstable,sotheaccuracyishigh,anditiswidelyusedinproduction.

Abriefhistoryofmining

ThefirstmolybdenumminedevelopedintheworldwastheKnabendepositintheKingdomofNorway.Theminestartedminingin1885.Duetothesmalldemandformolybdenumatthattime,miningstoppedduringthemine.Inthesecondhalfofthe19thcentury,molybdenumfirstbeganindustrialproductionintheUnitedStates,withanannualoutputofonlyafewtons.Sincethe20thcentury,thedemandformolybdenumhasincreasedyearbyyear,andmolybdenummininghasexpandedyearbyyear.Theannualoutputofmolybdenumintheworldhasincreasedrapidly.Attheend,itwillreach100,000tons.

mycountry'smolybdenummineswerefirstdiscoveredinthelastyearsoftheQingDynastyandbegantobeminedontheeveoftheFirstWorldWar.Atthattime,somevein-typemolybdenumdepositsalongthecoastofFujianandZhejiangandsomevein-typetungstendepositsassociatedwithmolybdenuminsouthernChinaweremainlymined.AttheendoftheWarofResistanceAgainstJapan,theYangjiazhangziMolybdenumMineinLiaoningwasexploitedbyJapaneseinvaders.Theannualoutputbeforeliberationwasonlyafewtons,andatmostitwasmorethantentons.Afterliberation,inordertomeettheneedsofsocialistconstructioninourcountry,threelarge-scalemolybdenumindustrybases(YangjiazhangziinLiaoning,JinduichenginShaanxi,andLuanchuaninHenan)havebeenestablishedsuccessively,aswellasseveralsmallandmedium-sizedmines,manycopperandtungstenmines.Theassociatedmolybdenumisalsorecovered,sothattheannualoutputofmolybdenumconcentratesinmycountryhasjumpedintotheworld'sadvancedranks.

Situationofmolybdenummines

Molybdenumreservesranksamongthetopintheworld,includingJinduiTown,HuaxianCounty,ShaanxiProvince,Huludao,Jilin,Shanxi,Henan,Fujian,Guangdong,Hunan,andSichuan.,Jiangxi,Gansu,InnerMongoliaandotherprovincesallhavemolybdenummineswithlargereservesandgooddevelopmentconditions.Theoutputoccupiesanimportantpositioninthecountry.Themolybdenummineralswithindustrialvaluearemainlymolybdenite(),andabout99%ofmolybdenumoreisminedinthestateofmolybdenite().mycountry'smolybdenumconcentrateismainlyexportedtoRussia,JapanandWesterncountries.

OnJuly21,2011,theprospectingreportoftheShapinggouMolybdenumDepositinGuanmiaoTownship,GuanmiaoTownship,JinzhaiCounty,surveyedbythe313GeologicalTeamoftheAnhuiBureauofGeologyandMineralResources,passedthereviewbytheAnhuiProvincialMineralResourcesReserveReviewCenter,withreservesof220Morethan10,000tons,rankingfirstinAsiaandsecondintheworld,withapotentialresourcevalueofmorethan600billionyuan.Thisistheonlysuper-largeworld-classmetaldepositdiscoveredinAnhuiProvince,endingthehistoryofnolarge-scalemetalminesinAnhuiinDabieMountains.

OnJune7,2010,thereporterlearnedfromtheBureauofGeologyandMineralResourcesofHenanProvincethatthethirdgeologicalsurveyteamoftheBureaudiscoveredanextra-largemolybdenumdepositinQianechong,XinyangshanCounty,withanamountofabout600,000tonsofmolybdenummetal.,Thepotentialeconomicvalueexceeds200billionyuan.

Qian'echongminingareaislocatedinHepengTownship,GuangshanCounty,34kilometersnorthofGuangshanCounty.

Area:11.6squarekilometers.

QianechongMolybdenumMinehasdelineated3mainmolybdenumorebodies.Inadditiontotheproven600,000-tonsuperlargemolybdenumorebody,therearetwoorebodiesunderexploration.

Accordingtoexperts,theresourcereservesofasingleorebodyofQianechongMolybdenumMineranksfirstinthecountry.ThesubmissionofthisresulthasmadethetotalamountofprovenmolybdenumresourcesatthenorthernfootoftheDabieMountainsrankamongthetopinthecountry.TheyalsobelievethatthesubmissionoftheQianechongsuperlargemolybdenumminewillnotonlylayasolidfoundationforXinyangastheprovince'smolybdenumindustrybase,butwillalsochangethedevelopmentpatternofthemolybdenumindustryinourprovince.

Prospectingofmolybdenumdeposits

Ofthe229molybdenumdepositsthathavebeenidentifiedinmycountry,aboutone-thirdhavebeenexplored.Geologicalexplorationofmolybdenumdepositsisdesignedformineconstructionindeterminingmineproductionscale,productplan,miningdevelopmentplan,mineoveralllayoutandmineconstructionlong-termplanning,aswellastheminingtechnicalconditionsofthehydrogeologyandengineeringgeologyofthemine,andtheperformanceoforeprocessingandsmelting.Itprovidesthenecessarygeologicalinformation,soitisafterthegeneralsurveyanddetailedgeologicalworkofthemolybdenumdeposit(area),theminingtechnicalconditionsofthedepositgeology,hydrogeologyandengineeringgeology,aswellasthetechnicalperformanceoforeprocessing,comprehensiveutilization,andminingareaThepreliminarytechnicalandeconomicevaluationoftheexternalconstructionconditionsisfeasible,andthentheexplorationworkiscarriedout.

Intheexplorationofmolybdenumminingareas,thefirststepistodeterminethetypeofexplorationbasedonthesize,shape,thicknessstabilityoftheorebody,thedegreeofstructuraldamage,andtheuniformityofthedistributionofthemaincomponentsoftheore.Thendeterminetheexplorationmethodandtheintervalbetweenexplorationprojectsaccordingtothetypeofexploration.The"SpecificationsforGeologicalProspectingofMolybdenumDeposits"formulatedbytheMinistryofGeologyandMineralResourcesandtheMinistryofMetallurgicalIndustryin1983dividedtheexplorationtypesofmolybdenumdepositsintofourcategories:

1)Thefirsttypeofexploration:theorebodyhasalargescaleandshapeSimple,stabletorelativelystablethickness,smallstructuraldamage,andrelativelyuniformdistributionofthemaincomponentsoftheore.DepositsbelongingtothistypeincludeJinduichenginShaanxiandSandaozhuanginHenan.

2)Thesecondexplorationtype:theorebodiesaremostlymedium-scaleextension,complexinshape,stabletounstablethickness,smalltolargeimpactsofstructuralfailureandintersperseddykes,andunevendistributionofmainorecomponentsTobeveryuneven.ThedepositsbelongingtothistypeincludeYangjiazhangziinLiaoning,WudaolinginHeilongjiang,andBaoshaninHunan.

3)ExplorationtypeIII:Theorebodiesaremostlylargeinscale,simpleinshape,stableinthickness,smallindamagetostructuresanddykes,andthemaincomponentsoftheorearerelativelyeventounevenlydistributed.ThedepositbelongingtothistypeisShangfanggou,Henan.

4)ExplorationtypeIV:thescaleoforebodyextensionissmalltomedium,theorebodyshapeiscomplextoverycomplex,thethicknessisunstabletoveryunstable,theimpactofstructuralfailureordykeinterleavingislargetolarge,Thedistributionofthemaincomponentsoftheoreisveryuneventoextremelyuneven.ThemineraldepositbelongingtothistypeofexplorationisShirengou,Jilin.

DevelopmentandUtilization

Puremolybdenumwireisusedforhightemperatureelectricfurnaceandelectricdischargemachiningandwirecutting;molybdenumsheetisusedtomakeradioequipmentandX-rayequipment;alloysteelcanbeaddedwithmolybdenumImproveelasticlimit,corrosionresistanceandmaintainpermanentmagnetism.Molybdenumisoneofthesevenmicronutrientelementsneededforplantgrowthanddevelopment.Withoutit,plantscannotsurvive.Animalsandfish,likeplants,alsoneedmolybdenum.

Classificationofmolybdenumore

1.Singlemolybdenumore

SuchastheYangjiazhangzimolybdenummineinLiaoning,theJinduichengmolybdenummineinShaanxi,andLuanchuaninHenanMolybdenummine,Ruyangmolybdenummine,Yechangpingmolybdenummine,DaheishanmolybdenummineinJilin,Lanjiagoumolybdenummine,HuangshanmolybdenummineandQingtianmolybdenummineareallsinglemolybdenumore.

Second,copper-molybdenumore

Themolybdeniteintheoresymbiosiswithvariouscoppersulfideminerals,suchasDexingCopperMine,BaoshanCopperMine,XiaosigouCopperMine,LinjiangCopperMineandXianlinbuCopperMine,etc.JinduiCityalsobelongstothiscategory.

3.Tungsten-molybdenumore

Themolybdeniteandtungstenoreintheoresymbiosis,amongwhicharePiaotangtungstenore,Guankengtungstenore,WenshuitungstenoresymbiosiswithwolframiteMine,DajishanTungstenMine,XihuashanTungstenMineandMiantuwoTungstenMine;theminesthatcoexistwithscheeliteincludeLuanchuanMolybdenumMine,ShizhuyuanTungstenandMolybdenumMine,etc.

4.Carbonaceouscopper-molybdenumore

Thiskindoforeisalsoverycommonabroad,andtheorecontainsorganiccarbonandcarbonaceousshale.ThemolybdeniteinJinkoulingco-existswithcarbon-containingsiliceousshale.Thiskindofcarbonrockisblack,dense,massive,andhard,withacarboncontentof2.94%.Thecarbonexistsinadispersedstateanddoesnotcombinewithminerals.Carbonaceousshaleiscomposedofmicrocrystallinequartz,finecarbonaceousparticles,asmallamountofferriteparticles,andargillaceouschlorite.Carbonaceousshaleandmolybdenitearefloatable,socarbonandmolybdenumseparationisrequired.

V.Vanadium-uranium-molybdenumore

Molybdenumoccursintheoreassubmicroscopiccrystals,andtheparticlesizeisextremelysmall,makingitdifficulttofloat.Thecarbonaceousvanadium-uranium-molybdenumorecontains15%to25%carbonandisthepigmentusedinthekilnsburnedbythelocalpeople.Thiskindoforeisverydifficulttobeselected,andonlychemicalbeneficiationcanbeused.

Molybdenumresources

Referstomolybdenumorereserves,reservebase,andresources.Molybdenumisarefractorymetalandanindispensablerawmaterialinmetallurgy,electrical,chemical,aviationandaerospaceindustries.Consumptionstructure:Thesteelindustryaccountsforabout75%,ofwhichalloysteelaccountsfor29%,stainlesssteelaccountsfor34%,andothersteels(tools,high-speed,caststeel)accountfor12%;inaddition,superalloys,metals,catalysts,andchemicalproductsaccountfor25%.AccordingtotheAnnualReviewofWorldMineralResources,thetotalconsumptionofmolybdenumintheworldin2002was127,000to135,000tons.Inthesameyear,theworld'sproductionofmolybdenummineswas133,900tons.Amongthem,theoutputoftheUnitedStates,China,andChileaccountedforabout76%oftheworld'stotal,especiallytheby-productsofChileanporphyrycopperoresurged.Inthepast10years,thegrowthrateofmolybdenumintheworldhasexceededthegrowthrateofconsumption,andtheinternationalmarkethasoversupplied.In2003,theworld'sprovenreservesofmolybdenumwere8.6milliontons.Amongthem,Chinais3.3milliontons,theUnitedStatesis2.7milliontons,Chileis1.1milliontons,Canadais450,000tons,andRussiais240,000tons.Thereservebaseis19milliontons(8.3milliontonsinChina,5.4milliontonsintheUnitedStates,2.5milliontonsinChile,etc.).Morethan80%ofthemolybdenumproducedintheworld'sminesmainlycomesfromtheby-productsofporphyry-typemolybdenumoreandporphyry-typecopperore.Theformer,suchastheUnitedStatesofQuatsemount,Claymax,Henderson,China'sHenanLuanchuan,ShaanxiJinduicheng;thelatter,suchasChile'sChuquicamata,etc.Itisestimatedthattheamountofmolybdenumresourcesidentifiedintheworldismorethan12milliontons.

Molybdenumreservesranksamongthetopintheworldinmycountry.TherearemolybdenumminesinJinduiTown,HuaxianCounty,ShaanxiProvince,Huludao,Jilin,Shanxi,Henan,Fujian,Guangdong,Hunan,Sichuan,Jiangxiandotherprovinces,andThereservesarelarge,thedevelopmentconditionsaregood,andtheoutputoccupiesanimportantpositioninthecountry.Themolybdenummineralswithindustrialvaluearemainlymolybdenite(MoS2),andabout99%ofmolybdenumoreisminedinthestateofmolybdenite(MoS2).Atpresent,mycountry'smolybdenumconcentrateismainlyexportedtoRussia,JapanandWesterncountries.

Expertsfromthe313geologicalteamoftheAnhuiProvincialGeologicalBureauofficiallyannouncedthattheprovenreservesoftheShapinggouMolybdenumDepositinGuanmiaoTownship,JinzhaiCountyaremorethan500,000tons,andtheresourcevalueexceeds200billionyuan.ThisisthecurrentdiscoveryinAnhuiProvince.Theonlysuper-largemetaldepositinDabieshanendedthehistoryofnolarge-scalemetaldepositsinAnhui.

Qian'echongminingareaislocatedinHepengTownship,GuangshanCounty,34kilometersnorthofGuangshanCounty.

Molybdenumorebeneficiationequipment

Molybdenumorebeneficiationequipmentmainlyincludes:feeder,jawcrusher,ballmill,spiralclassifier,miningmixingbarrel,flotationmachine,concentrationMachines,dryers,etc.andrelatedattachedmachines.

Introductiontomolybdenumore

Molybdenumisametalelement,withalead-greycolorandmetallicluster,belongingtothehexagonalsystem.4.7～4.8,hardspecificgravityis1～1.5,meltingpointis795℃,iseasilyoxidizedtoformwhenheatedto400～500℃,bothnitricacidandaquaregiaDecomposemolybdenite().Molybdenumhastheadvantagesofhighstrength,highmeltingpoint,corrosionresistance,wearresistance,etc.,soithasbeenwidelyusedinindustry.

mycountry'smolybdenumbeneficiationhasahistoryofhalfacentury.ThemolybdenumbeneficiationplanthasdevelopedfromtheonlyYangjiazhangzimolybdenumbeneficiationplantintheoldChinatomorethan50molybdenumbeneficiationplants,copperandmolybdenumbeneficiMolybdenumconcentratorandmolybdenum-bismuthconcentratorproducemolybdenumconcentrates.Thegapbetweenmolybdenumorebeneficiationtechnologyandadvancedforeigncountrieshasbecomesmallerandsmaller.

Molybdenumorebeneficiationprocess

Themainmethodofmolybdenumbeneficiationinmycountryisflotation.Inthedeepselectionofmolybdenum-basedorescontainingtraceamountsofcopper,apartialmixingpriorityflotationprocessisused.ThevaluablemineralsoftheoreprocessedbytheJinduichengMolybdenumConcentratoraremolybdenite,pyriteandasmallamountofchalcopyrite.Itadoptsmolybdenum-coppermixedflotation,tailingsflotationpyrite,copper-molybdenumseparationandPartialmixingofmolybdenumconcentrate-priorityflotationprocess.Atpresent,ourcountryalsorecoversmolybdenumfromcopper-molybdenumore.Thecommonprocessiscopper-molybdenummixedflotation,thencopper-molybdenumseparationandmolybdenumconcentrateselection.

Molybdenumorebeneficiationprocessesinclude:molybdenumbeneficiation,copper-molybdenumbeneficiation,tungstenandmolybdenumbeneficiation,andmolybdenum-bismuthbeneficiationtoproducemolybdenumconcentrate.

Themaincommonlyusedmethodsarethesodiumsulfidemethodandthesodiumcyanidemethodtoseparatecopperandmolybdenumandtheselectionofmolybdenumconcentrates.Thenumberoftimesofmolybdenumbeneficiationmainlydependsonthetotalenrichmentratioofmolybdenum.Generally,ifthetotalenrichmentratioishigh,thenumberofselectionsisusuallymore;ifthetotalenrichmentratioislow,thenumberofselectionsisusuallyless.Forexample,theoriginaloregradeoftheoreprocessedbytheLuanchuanMolybdenumConcentratorisrelativelyhigh(0.2%to0.3%),andtheenrichmentratiois133to155.Theoriginaldesignforthetotalnumberofbeneficiationis7times.Themolybdenumgradeoftheraworeprocessedbytheplantisabout0.1%,theenrichmentratiois430-520,andthetotalnumberoftimesofbeneficiationreaches12times.Inrecentyears,inordertomeettheneedsofmolybdenumconcentrateexport,theJinduichengMolybdenumConcentratorhasadoptedthehydrochloricacid-ferricchlorideleachingmethodtoremoveimpuritiesinthemolybdenumconcentrate.

Descriptionofmolybdenumorebeneficiationprocess:

1.Molybdenumoreiscoarselycrushedbyajawcrusher,andthencrushedtoareasonablefinenessbyafinejawcrusher.Itissenttothesiloviatheelevator.

2.Thefeederisevenlyfedintotheballmill,andtheoreisgroundbytheballmill.

3.Thegroundorefinesenterthespiralclassifier.Thespiralclassifierusestheprincipleofdifferentspecificgravityofsolidparticlesanddifferentsedimentationspeedsintheliquidtocleanandclassifytheoremixture.

Four.Afterpassingthroughthemixingtank,itissenttotheflotationmachineforflotationoperation.Accordingtodifferentmineralcharacteristics,differentcorrespondingflotationreagentsareadded.Intheflotationmachine,thebubblesandmineralparticlesaredynamicallycollidedandthebubbleparticlesarecombinedstaticallytoseparatetherequiredmineralsfromothersubstances.Conducivetotheseparationoffine-grainedorfine-grainedmolybdenumore.

Fifth,useahigh-efficiencythickenertoremovethewaterinthemineralconcentrateafterflotationtoreachthenationalstandard.

Fromtheperspectiveofsomemolybdenumoreconcentratorsinmycountry'snon-ferroussystem,thegradesoftheprocessedraworevarygreatly,withthehighestbeingabove0.3%,thelowbeingbelow0.1%,andsomeareonly0.02%.Theactualrecoveryratethroughmolybdenumorebeneficiationequipmentisover80%.Thegradeoftheobtainedconcentrateisbetween45%and54%,thegradeoftailingsismostlyaround0.02%,thehighis0.04%,andthelowis0.01%.

Inthecurrentindustrialproductionofmolybdenum,theprocessofmolybdenumorebeneficiationequipmentmainlyusesmolybdeniteconcentrateforsmelting,includingoxidationroasting,extractionofpuremolybdenumtrioxide,andreductionroastingintometallicmolybdenumpowder.Link.

Themolybdenumconcentrateisfirstoxidizedandroastedinareverberatoryfurnace,amulti-hearthfurnace,aboilingfurnace,oraflashfurnace.Afterdesulfurization,akindofimpuremolybdenumtrioxide(40%～48%)isroasted.Sandandcalcinecanbeproducedfromferromolybdenumalloybymetalheatingmethodorsiliconheatingmethod.Therearetwomethodsforproducingpuremolybdenumtrioxidefromcalcine:oneissublimationmethod,andtheotherishydrometallurgy.Itisleachedandpurifiedwithammoniasolutiontoremoveimpurities,thenthemolybdenumisprecipitatedinthestateofammoniumparamolybdate(56%)ormolybdicacidbycrystallizationorhydrochloricacidneutralization,andthenroastedtobecomepuremolybdenumtrioxide.Finally,puremolybdenumtrioxideismadeintometalmolybdenumpowder(99.7%-99.9%)byhydrogenreductionmethod,andthenmadeintomolybdenumingotsormolybdenumbarsbypowdermetallurgyorfurtherarcsmelting.

Currently,thesmeltingprocessofmolybdenumconcentratesathomeandabroadhasbeenstudiedandtestedsomenewtechnologiesandnewmethods.Forexample,molybdeniteconcentratesarenotoxidizedandroasted,andtheyaredirectlyextractedbyoxygenpressurecookingorbacterialleaching.Molybdenumtrioxide.Thelow-gradeoxideoreisleachedwithsulfuricacid,andpuremolybdenumtrioxideisextractedfromthesolutionbyionexchangeorextraction.Inaddition,thesmeltingmethodsofmolybdenumconcentrateincludelimeroasting,nitricacidleaching,sodiumhypochloriteleaching,andelectro-oxidationleaching.

Therheniuminthemolybdenumconcentrateismainlyrecoveredfromtheoxidativeroastingfluegasleachingliquidortheoxygenpressurecookingliquidofthemolybdenumconcentrate,andthenthehighrheniumismadefromthesolutionbytheextractionmethodortheionexchangemethodPotassiumacidorammoniumperrhenateisthenreducedtomakehigh-purityrheniumpowder.

Theharmfulimpuritiesinmolybdenumconcentrates,suchascopper,lead,tin,arsenic,phosphorus,calcium,silicondioxide,etc.,notonlyaffectthequalityofmolybdenumproducts,butalsoaffecttheprocessandequipmentofmolybdenumsmelting.Andpollutetheenvironment.Itneedstobestrictlycontrolledbeforesmelting,orrecycledduringsmelting,sothatitbecomesausefulcomponentandgreatlyimprovestheindustrialvalueofmolybdenumdeposits.

Molybdenite

Sulphidemineralwhosechemicalcompositionis.Therearedifferenttypes,whichbelongtothehexagonalandtrigonalcrystalsystems.Containing59.94%molybdenum,itisthemostimportantmineralrawmaterialforextractingmolybdenum.Itoftencontainsrhenium,whichisthemineralwiththehighestrheniumcontentknowninnature,anditisalsothemainmineralrawmaterialforrefiningrhenium.Molybdeniteisleadgraywithstrongmetallicluster.Withcompletebottomcleavage.Thecrystalisintheshapeofahexagonalplate.Usuallyitisproducedinflake,scalyorfinelydispersedgranularform.Molybdeniteisthemostwidelydistributedmolybdenummineral,mainlyproducedinhighandmediumtemperaturehydrothermalfluidsandskarndeposits.Itiseasytoweatherintomolybdenumbloomsonthesurface.ClaymaxandYulard-HendersoninColorado,USAaretheworld-famousmolybdenitedeposits.China'sHenan,Shaanxi,Shanxi,Liaoningandotherprovincesalsohaveproduction,andthetotalreserveshaveleapttotheforefrontoftheworld.

Introduction

Molybdenite

Molybdeniteisadisulfideofmolybdenumandisthemostimportantmolybdenumresource.Therearedifferenttypes,whichbelongtothehexagonalandtrigonalcrystalsystems.Molybdenumisusedtomakeelectricalandelectroniccomponentssuchasfilamentholders,anodesandgrids,andheatingelementsforelectricfurnaces.Molybdenitealsooftencontainsrhenium,anditisalsothemineralwiththehighestrheniumcontent,soitisalsothemostimportantmineralforrefiningrhenium(rheniumcannowbedirectlyextractedbecausepurerheniumhasnowbeenfound)[1].Molybdeniteisverysoftandharderthannails.Generally,theyareflakesorfinegranules,leadgray,andhaveastrongmetallicluster.MolybdeniteisproducedinHenan,Shaanxi,Liaoningandotherplacesinmycountry.

Chemicalcomposition:MoS2,Momolybdenum59.94%,Ssulfur40.06%;

Identificationcharacteristics:molybdeniteischaracterizedbyitsleadgray,metallicluster,lowhardness,andextremelycleavageonthebottom.Complete,highspecificity,stronggloss,lightercolorandstreaks;

Graphitedifference;heavierthangraphite,whileslightlyblue,graphiteisslightlybrown;intermsofstreaks,molybdenitestripsThemarkisgreen,butthegraphiteisblack.Burnitintheairorboilitinnitricacidtogetmolybdenumtrioxide.

Occurrenceofgenesis:Itismainlycausedbyhighandmediumtemperaturehydrothermalfluids,anditsdepositsaregeneticallyrelatedtoacidrocks;

Themostimportantmolybdenumdepositsareporphyrymolybdenumdeposits;Symbiosiswithcassiterite,wolframite,bismuthite,arsenopyrite,etc.orsymbiosiswithgarnet,diopside,epidote,scheelite,etc.

Famousorigins:Theworld'sfamousoriginsincludetheUnitedStatesandAustralia,NewSouthWales,Canada,Quebec,Ontario,Norway,Sweden,theUnitedKingdom,Mexico,China'sLiaoning,Henan,Shanxi,Shaanxiandotherplaces.

Crystalmorphology

Compoundhexagonalbipyramidalcrystals;

Thecrystalsareintheshapeofhexagonalplatesandplatesparalleltoc(0001);

Themainsimplexare:paralleldouble-sidedc(0001),hexagonalcolumnm(10-10),hexagonaldoublecones(10-15)andsoon.

Crystalstructure

Molybdenite

Crystalsystemandspacegroup:hexagonalsystem(2Htype),spacegroupisD46h—P63/mmc;tripartiteThecrystalsystem(3Rtype),thespacegroupisC5-R3m.

Unitcellparameters:a0=3.15angstroms,co=12.30angstroms(2Htype),z=2,a0=3.16angstroms,c0=18.33angstroms(3Rtype).

Physicalproperties

Hardness:

Molybdenite

1-1.5,canmakestreaksonpaper

Specificgravity:5.05g/cm3

Cleavage:(0001)extremelycomplete

Color:leadgray

Molybdenum

Stripe:brightgray

Transparency:opaque

Gloss:metallicluster

Luminescence:none

Others:thesheetisflexibleandhasagreasyfeel

Opticalproperties

Thereflectioncolorisgrayandwhite.Reflectance:Rois36.0(greenlight),31.5(orangelight),30.5(redlight);Reare15.5,18,and15,respectively.Strongdoublereflection,Ro-whitebeltsnowcyan,Re-yellow.Strongheterogeneity.

Mainuses

Usedtoextractmolybdenum,makemolybdenumsteel,molybdicacid,molybdateandothermolybdenumcompounds.

Molybdenumisametalelementthatwasdiscoveredrelativelylate.ItwasonlyextractedfrommolybdenitebySwedishchemistsin1792.

Thecolorofmolybdeniteispureleadgraywithmetallicluster.Thehardnessis1-1.5,andthespecificgravityis4.7-5.0.Generally,molybdeniteisblackflake,scaly,disseminated,granularorcleavable,opaque.Ithasasofttextureandiseasilysplitintoabendablebutinelasticsheetwithaslipperyfeel.Analysisshowsthatitselectricalconductivityincreaseswithincreasingtemperature,anditisresistanttohightemperatures.Itisusedtoextractmolybdenumandmakemolybdenumsteel,molybdicacid,molybdateandothermolybdenumcompounds.

Mineralogistsbelievethatmostofthemolybdenitedepositswithindustrialvaluearerelatedtoundergroundhotliquids,andaremostwidelydistributedinquartzveinsorquartzizedrocks.

Characteristicsofrawmaterials

Molybdenite()isthemostwidelydistributedamongthemorethan30molybdenum-containingmineralsknowninnatureandhaspracticalindustrialvalueMolybdenumminerals.Othermorecommonmolybdenum-containingmineralsincludeiron-molybdenum([()·8]),calciummolybdate(

),colormolybdenumleadore(),colloidalsulfidemolybdenumore(),bluemolybdenumore(·n

)etc.

Therearepolytypesofmolybdenite.Experimentsshowthattheappearanceofpolytypesisrelatedtotheformationtemperature.Theformationtemperatureof2H-typemolybdeniteHigherthan3Rmolybdenite.Thetemperaturefromlowtohighformsamorphous→colloid→3Mo→2HMo.Thetemperaturemeasurementdatashowsthattheformationtemperatureofmolybdenitehasawiderange,fromafairlyhightemperaturetoarelativelylowtemperature,andalargeamountofitisformedinthehightomediumtemperaturestage.Undertheactionofhydrothermalfluid,precipitatesunderacidicconditions,thatis,molybdeniteismoststableunderacidicconditions.Whenthesolutionturnstoneutral,molybdenumbecomessolublethiomolybdateandMolybdateisactiveagain.Underlowandnormaltemperatureconditions,generatescollosulfidemolybdenum()inastrongacidreductionenvironment,andtheproductafteroxidationisbluemolybdenum()section>·n).Inexogenouseffects,molybdenumisandhasstrongmobility.

Relatedhistory

ThefirstmolybdenumminedevelopedintheworldwastheKnabendepositinNorway.Theminestartedminingin1885.Duetothesmalldemandformolybdenumatthattime,miningstoppedduringthemine.Inthesecondhalfofthe19thcentury,molybdenumfirstbeganindustrialproductionintheUnitedStates,withanannualoutputofonlyafewtons.Sincethe20thcentury,thedemandformolybdenumhasincreasedyearbyyear,andmolybdenummininghasexpandedyearbyyear.Theannualoutputofmolybdenumintheworldhasincreasedrapidly.Itreached100,000tonsinthelate1970s.

China'smolybdenummineswerefirstdiscoveredinthelateQingDynastyandbegantobeminedontheeveoftheFirstWorldWar.Atthattime,somevein-typemolybdenumdepositsalongthecoastofFujianandZhejiangandsomevein-typetungstendepositsassociatedwithmolybdenuminsouthernChinaweremainlymined.AttheendoftheWarofResistanceAgainstJapan,theYangjiazhangziMolybdenumMineinLiaoningwasexploitedbyJapaneseinvaders.Theannualoutputbeforeliberationwasonlyafewtons,andatmostitwasmorethantentons.Afterliberation,inordertomeettheneedsofChina’ssocialistconstruction,threelargemolybdenumindustrybases(YangjiazhangziinLiaoning,JinduichenginShaanxi,andLuanchuaninHenan)havebeenestablishedsuccessively,aswellasseveralsmallandmedium-sizedmines,manycopperminesandtungstenmines.Theminealsorecoverstheassociatedmolybdenum,thusmakingChina'sannualoutputofmolybdenumconcentratesleapintotheworld'sadvancedranks.

Impactontheenvironment

I.Healthhazards

Invasionmethods:inhalation,ingestion.Healthhazards:irritatingtoeyesandskin.Partofthecontactsdevelopedpneumoconiosisdisease,consciouslydyspnea,generalfatigue,dizziness,chestpain,cough,etc.

2.Toxicologicalinformationandenvironmentalbehavior

Acutetoxicity:LD506.1mg/kg(ratoral)Hazardcharacteristics:Thepowdercanburnorevenexplodewhenexposedtohighheatandopenflame.Itcanreactwithoxidants.

Combustion(decomposition)product:molybdenumoxide.

Leakageemergencytreatment

Isolatetheleakingcontaminatedarea,setupwarningsignsaround,andcutoffthefiresource.Itisrecommendedthatemergencypersonnelwearself-containedbreathingapparatusandchemicalprotectiveclothing.Usetoolsthatdonotgeneratesparkstosweepupcarefullytoavoiddust,andtransporttothewastedisposalsite.Washtheleakedcontaminatedareawithwater,andputthedilutedwashingwaterintothewastewatersystem.Ifthereisalargeamountofleakage,collectandrecycleordisposeofitafterharmlesstreatment.

Protectivemeasures

Respiratoryprotection:Workersmustweargasmasks.Wearself-containedbreathingapparatuswhennecessary.

Eyeprotection:wearchemicalsafetyglasses.

Protectiveclothing:Wearanti-staticoveralls.

Handprotection:Wearchemical-proofgloves.

Other:Smoking,eatinganddrinkingareprohibitedattheworksite.Afterwork,takeashowerandchangeclothes.Payattentiontopersonalhygiene.

Firstaidmeasures

Skincontact:Rinsethoroughlywithsoapandwater.Seekmedicalattention.Eyecontact:Openeyelidsandrinsewithrunningwaterfor15minutes.Seekmedicalattention.

Inhalation:Leavethescenetoaplacewithfreshair.Seekmedicalattention.

Ingestion:Ifyoutakeitbymistake,drinksomewarmwatertoinducevomiting.Seekmedicalattention.