Lub Luag Haujlwm ntawm Catalysts hauv Metallurgical Processes
Metallurgy yog ib ceg ntawm kev tshawb fawb thiab thev naus laus zis uas kawm txog kev rho tawm cov hlau los ntawm cov hlau, kev ntxuav, kev sib xyaw, thiab kev ua kom zoo nkauj thiab kev kho kom ua tiav cov khoom siv uas xav tau. Tom qab ntau theem no, cov catalysts ua lub luag haujlwm tseem ceeb dua. Catalysts yog cov tshuaj uas ua kom cov tshuaj tiv thaiv sai dua yam tsis tas yuav siv tas mus li. Txawm hais tias cov catalysts feem ntau raug tham txog hauv kev lag luam tshuaj lom neeg, xws li petrochemicals lossis kev tsim chiv, lawv daim ntawv thov hauv metallurgy tam sim no nthuav dav sai, feem ntau yog vim muaj kev thov kom siv hluav taws xob zoo, txo cov pa phem, thiab txhim kho cov khoom hlau zoo.
Vim li cas cov catalysts thiaj tseem ceeb hauv metallurgy?
Cov txheej txheem metallurgical feem ntau muaj cov tshuaj tiv thaiv kub siab, siv zog ntau, thiab kev sib cuam tshuam nyuaj ntawm cov khoom khov, kua, thiab roj. Cov catalysts tuaj yeem pab txo qhov zog ua haujlwm ntawm cov tshuaj tiv thaiv, ua rau lawv ua tiav sai dua lossis ntawm qhov kub qis dua. Yog li, cov catalysts muaj peev xwm txo cov nqi khiav lag luam, txuas ntxiv lub neej ntawm cov khoom siv, thiab txo qhov tsim cov khoom tsis xav tau. Ntxiv mus, cov catalysts tuaj yeem ua rau muaj kev xaiv ntau ntxiv, qhov kev nyiam ntawm cov tshuaj tiv thaiv los tsim cov khoom tshwj xeeb, uas yog qhov tseem ceeb rau kev ua kom hlau thiab kev tswj hwm cov khoom sib xyaw.
Cov tshuaj catalysts nyob rau theem rho tawm hlau (pyrometallurgy thiab hydrometallurgy)
Hauv kev rho tawm hlau, cov hlau yuav tsum tau ua tiav kom cais cov hlau muaj nqis ntawm cov khoom tsis huv. Hauv cov txheej txheem pyrometallurgical, kev txo cov hlau oxides feem ntau yog ua tiav ntawm qhov kub siab siv cov pa roj carbon, carbon monoxide, lossis hydrogen. Hauv qee lub tshuab, cov catalysts tuaj yeem ua kom nrawm dua qhov kev txo qis lossis pab txhawb kev tsim cov pa roj txo qis. Piv txwv li, hauv cov txheej txheem hydrogen-raws li rau kev txo cov hlau ncaj qha, qee cov catalysts tuaj yeem pab txhim kho cov tshuaj tiv thaiv kinetics, ua rau cov txheej txheem ua haujlwm tau zoo dua thiab tsim cov pa roj carbon tsawg dua li kev txo qis coke-raws li.
Lub caij no, hauv hydrometallurgy, cov hlau raug rho tawm siv cov kuab tshuaj aqueous los ntawm kev leaching, kev ntxuav cov kua, thiab kev nag lossis electrowinning. Thaum lub sijhawm leaching, cov catalysts tuaj yeem ua haujlwm ua cov neeg sawv cev redox, ua kom cov ntxhia yaj sai dua. Hauv kev leaching kub, piv txwv li, cyanide siv, uas tsim cov khoom sib xyaw nrog kub. Txawm hais tias cov txheej txheem no tsis yog "catalytic" nruj me ntsis, qhov ntxiv ntawm oxygen lossis qee cov neeg sawv cev oxidizing tuaj yeem ua rau kom muaj kev cuam tshuam ntau dua. Hauv qee cov refractory ores, catalysts lossis redox mediators tuaj yeem pab qhib cov qauv ntxhia kom pab txhawb kev yaj hlau.
Cov catalysts hauv kev ntxuav thiab tshem tawm cov khoom tsis huv
Kev ua kom cov hlau zoo yog ib kauj ruam tseem ceeb vim tias txawm tias cov khoom me me uas tsis muaj kuab lom kuj tuaj yeem hloov cov khoom siv kho tshuab ntawm cov hlau, kev tiv taus xeb, thiab kev coj hluav taws xob. Cov tshuaj catalysts tuaj yeem siv los ua kom cov tshuaj sib txuas ntawm cov khoom tsis muaj kuab lom sai dua lossis hloov cov khoom tsis muaj kuab lom mus rau hauv cov qauv yooj yim dua.
Piv txwv li, thaum ua kom cov hlau uas yaj lawm, muaj kev sib xyaws ntawm cov khoom tsis huv (xws li sulfur lossis phosphorus) thiab slag. Txawm hais tias slag tsis yog ib qho catalyst hauv cov lus txhais classical, qee cov khoom slag tuaj yeem yog "catalytic" vim tias lawv ua kom cov huab hwm hloov pauv thiab cov tshuaj sib xyaws ua ke sai dua. Kev ntxiv qee cov khoom ntxiv tuaj yeem ua rau slag muaj peev xwm khi sulfur (desulfurization), ua rau sulfur dim ntawm cov hlau uas yaj sai dua. Cov txheej txheem no cuam tshuam nrog kev hloov pauv hauv slag viscosity, kev ua haujlwm tshuaj lom neeg, thiab thaj chaw nto, txhua yam uas cuam tshuam rau qhov nrawm ntawm kev sib xyaws ua ke.
Hauv cov txheej txheem ua hlau, kev tswj cov tshuaj oxidation thiab txo qis ntawm cov theem ntawm lub tshuab hloov pauv oxygen yooj yim (BOC) lossis lub tshuab hluav taws xob arc (EARC). Cov catalysts lossis cov tshuaj txhawb nqa kev ua haujlwm tuaj yeem pab tswj kev tsim CO, CO₂, thiab cov tshuaj decarburization (carbon txo qis), ua rau cov txheej txheem ruaj khov thiab ua haujlwm tau zoo dua.
Lub luag haujlwm ntawm cov catalysts hauv cov txheej txheem sintering thiab pellet ua
Ua ntej ua cov hlau ntxiv, feem ntau yuav tsum tau sintering lossis pelletizing kom zoo dua qhov permeability thiab qhov zoo ntawm cov khoom noj mus rau lub cub tawg lossis lub tshuab txo qis ncaj qha. Thaum lub sijhawm no, muaj ntau yam kev hloov pauv oxidation-reduction, carbonate decomposition, thiab slag phase tsim. Kev ntxiv qee yam khoom siv tuaj yeem ua haujlwm ua catalysts lossis promoters, ua kom nrawm dua ntawm kev tsim cov theem sib txuas, ua kom lub zog ntawm sinter / pellet nce ntxiv, thiab ua kom zoo dua porosity. Qhov no ua rau muaj kev sib xyaw ua ke ruaj khov dua vim muaj kev faib tawm ntawm cov roj txo qis hauv cov khoom siv.
Catalyst hauv kev tswj hwm pa phem thiab ib puag ncig
Ib qho ntawm cov luag haujlwm tseem ceeb tshaj plaws ntawm cov tshuaj catalysts hauv kev lag luam niaj hnub no yog kev tswj cov pa phem. Cov txheej txheem smelting thiab refining tsim cov pa roj xws li CO, NOx, SOx, nrog rau cov organic compounds volatile thiab particulate matter. Catalytic technology ua rau cov pa phem hloov pauv mus rau hauv cov tshuaj muaj kev nyab xeeb dua ua ntej lawv raug tso tawm mus rau hauv huab cua.
Piv txwv li, cov tshuaj catalysts oxidation tuaj yeem hloov CO mus rau CO₂ tau zoo, thaum cov tshuaj catalytic txo qis (SCR) tuaj yeem txo cov pa phem NOx los ntawm kev hloov lawv mus rau N₂ thiab H₂O siv ammonia lossis urea ua cov tshuaj txo qis. Hauv cov chaw ua haujlwm loj hauv cov hlau, kev siv cov txheej txheem catalytic no pab ua kom tau raws li cov cai ib puag ncig nruj dua thaum txhim kho huab cua zoo nyob ib puag ncig cov nroj tsuag.
Tsis tas li ntawd xwb, cov tshuaj catalysts kuj tseem ua lub luag haujlwm hauv kev rov qab tau lub zog los ntawm cov pa roj tawm. Cov pa roj uas tseem muaj CO lossis H₂ tuaj yeem hlawv tau hauv txoj kev tswj hwm lossis ua tiav nrog cov tshuaj catalysts los tsim cov cua sov lossis cov khoom siv tshuaj lom neeg. Cov kev txhim kho tsis ntev los no txawm tias taw qhia txog kev siv cov pa roj tawm hauv cov hlau ua cov pa roj carbon rau kev tsim cov tshuaj lom neeg, yog li ua rau muaj kev siv lub tswv yim kev lag luam ncig.
Cov tshuaj catalysts hauv kev siv hlau dua tshiab thiab kev lag luam ncig
Nrog rau qhov kev thov kom muaj hlau ntau zuj zus thiab cov khoom siv hlau tsawg, kev siv dua tshiab kuj tseem ceeb zuj zus. Cov tshuaj catalysts tuaj yeem txhim kho kev ua haujlwm ntawm cov khoom pov tseg, tshwj xeeb tshaj yog rau kev cais cov organic contaminations lossis txhim kho kev rov qab tau cov hlau muaj nqis los ntawm e-pov tseg.
Piv txwv li, hauv kev ua cov khib nyiab hluav taws xob (e-pov tseg), cov tshuaj catalysts tuaj yeem siv rau hauv theem pyrolysis lossis gasification los rhuav tshem cov polymers thiab resins, ua rau cov khoom hlau yooj yim cais. Cov tshuaj catalysts kuj tseem tuaj yeem pab hloov cov roj pyrolysis mus rau hauv roj lossis cov khoom siv tshuaj muaj nqis, txo cov khib nyiab kawg thiab ua kom cov txheej txheem rov ua dua tshiab zoo dua.
Hauv cov roj teeb lithium-ion, kev rov qab tau cov hlau xws li cobalt, nickel, manganese, thiab lithium tuaj yeem cuam tshuam nrog cov kauj ruam hydrometallurgical. Kev siv cov catalysts lossis redox mediators hauv leaching tuaj yeem ua rau muaj kev xaiv ntau dua thiab txo qhov xav tau cov tshuaj lom neeg hnyav, ua rau cov txheej txheem zoo dua rau ib puag ncig.
Cov teeb meem ntawm kev siv cov catalysts hauv metallurgy
Txawm hais tias lawv muaj txiaj ntsig zoo, kev siv cov catalysts hauv cov chaw ua hlau tsis yog ib txwm yooj yim. Cov txheej txheem metallurgy feem ntau tshwm sim ntawm qhov kub thiab txias heev, hauv cov huab cua corrosive, thiab nyob rau hauv qhov muaj cov khoom khov uas tuaj yeem ua puas lossis ua kom cov catalyst tsis ua haujlwm. Cov catalysts tuaj yeem ntsib sintering (kev sib sau ua ke ntawm cov khoom me me ntawm qhov kub siab), lom los ntawm sulfur lossis cov hlau hnyav, thiab fouling vim muaj hmoov av. Yog li ntawd, kev tsim catalyst rau metallurgy yuav tsum xav txog kev ruaj khov thermal, kev tiv thaiv cov tshuaj lom, thiab kev tsim kho dua tshiab.
Los ntawm kev xam pom txog kev lag luam, cov tshuaj catalysts uas muaj hlau zoo li platinum lossis palladium muaj txiaj ntsig zoo tab sis kim heev. Lwm txoj hauv kev yog los tsim cov tshuaj catalysts uas siv cov hlau hloov pauv oxides, zeolites, lossis cov ntaub ntawv sib xyaw uas pheej yig dua tab sis tseem tiv taus cov xwm txheej ua haujlwm hauv hlau. Kev tshawb fawb kuj tseem tsom mus rau nanocatalysts thiab cov tshuaj catalysts uas muaj cov qauv, uas muaj thaj chaw siab thiab tiv taus kev ua haujlwm tsis zoo.
Xaus
Cov tshuaj catalysts ua lub luag haujlwm tseem ceeb hauv cov txheej txheem metallurgical, txij li kev rho tawm thiab kev ua kom huv, los ntawm kev txhim kho qhov zoo ntawm cov khoom siv raw xws li sinter thiab pellets, mus rau kev tswj hwm pa phem thiab kev tsim cov thev naus laus zis rov ua dua tshiab. Nrog kev pab los ntawm cov tshuaj catalysts, kev lag luam metallurgical tuaj yeem txhim kho kev siv hluav taws xob zoo, txo cov nqi, txo kev ua qias tuaj, thiab txhawb nqa kev hloov mus rau cov txheej txheem tsim hlau uas ruaj khov dua. Mus tom ntej, kev tsim cov tshuaj catalysts uas tiv taus kub siab, tsis muaj tshuaj lom, thiab pheej yig yuav yog qhov tseem ceeb rau kev ua kom muaj kev tsim kho tshiab catalytic kom dav dua hauv cov nroj tsuag metallurgical thoob ntiaj teb.
