Kev npaj ntawm
Vim tias muaj zog heev ntawm Calcium Hlau, nws yog tsim los ntawm electrolytic molten calcium chloride los yog calcium hydroxide yav dhau los. Hauv xyoo tas los no, txoj kev txo qis tau maj mam dhau los ua txoj hauv kev tseem ceeb ntawm kev tsim cov calcium hlau.
Txoj kev txo qis yog siv hlau aluminium kom txo cov txiv qaub nyob rau hauv lub tshuab nqus tsev thiab kub, thiab tom qab ntawd kho kom tau txais calcium.
Txoj kev txo qis feem ntau yog siv limestone ua raw khoom, calcined calcium oxide thiab txhuas hmoov raws li tus neeg sawv cev txo.
Cov pulverized calcium oxide thiab txhuas hmoov yog sib xyaw ua ke nyob rau hauv ib qho kev faib ua feem, nias rau hauv cov blocks, thiab reacted nyob rau hauv 0.01 nqus tsev vacuum thiab 1050-1200 âº̓ kub. Tsim cov calcium vapor thiab calcium aluminate.
Cov qauv tshuaj tiv thaiv yog: 6CaO 2Alâ, 3Ca 3CaOâ ¢ Al2O3
Qhov txo qis calcium vapor crystallizes ntawm 750-400 ° C. Tom qab ntawd cov crystalline calcium yog melted thiab casted nyob rau hauv kev tiv thaiv ntawm argon kom tau ib tug ntom calcium ingot.
Tus nqi rov qab ntawm calcium uas tsim los ntawm kev txo qis feem ntau yog li 60%.
Vim tias nws cov txheej txheem thev naus laus zis kuj yog qhov yooj yim, txoj kev txo qis yog txoj hauv kev tseem ceeb rau kev tsim cov hlau calcium hauv xyoo tas los no.
Lub combustion nyob rau hauv ib txwm tej yam kev mob yuav yooj yim mus txog lub melting point ntawm metallic calcium, yog li nws yuav ua rau combustion ntawm hlau calcium.
Cov electrolysis ua ntej yog txoj kev sib cuag, uas tom qab ntawd tau txhim kho rau cov kua cathode electrolysis.
Kev sib cuag electrolysis yog thawj zaug siv los ntawm W. Rathenau hauv xyoo 1904. Cov electrolyte siv yog sib xyaw ntawm CaCl2 thiab CaF2. Lub anode ntawm electrolytic cell yog lined nrog carbon xws li graphite, thiab cathode yog ua los ntawm hlau.
Electrolytically desorbed calcium ntab rau saum npoo ntawm electrolyte thiab condenses ntawm cathode nyob rau hauv kev sib cuag nrog steel cathode. Raws li cov electrolysis zuj zus, cov cathode nce raws li, thiab cov calcium ua ib tug carrot-zoo li tus pas nrig ntawm lub cathode.
Qhov tsis zoo ntawm calcium ntau lawm los ntawm txoj kev sib cuag yog: kev siv ntau ntawm cov khoom siv raw, siab solubility ntawm Calcium Hlau hauv electrolyte, tsis tshua muaj kev ua haujlwm tam sim no, thiab cov khoom tsis zoo (kwv yees li 1% chlorine cov ntsiab lus).
Txoj kev ua kua cathode siv cov tooj liab-calcium alloy (muaj 10% -15% calcium) ua kua cathode thiab graphite electrode ua cov anode. Electrolytically desorbed calcium yog tso rau ntawm cathode.
Lub plhaub ntawm lub cell electrolytic yog ua los ntawm cam khwb cia hlau. Cov electrolyte yog sib xyaw ntawm CaCl2 thiab KCI. Copper yog xaiv los ua cov alloy muaj pes tsawg leeg ntawm cov kua cathode vim tias muaj qhov dav heev tsawg melting point cheeb tsam nyob rau hauv lub siab calcium ntsiab lus cheeb tsam nyob rau hauv lub tooj liab-calcium theem daim duab, thiab ib tug tooj liab-calcium alloy nrog ib tug calcium ntsiab lus ntawm 60% -65. % tuaj yeem npaj tau qis dua 700 ° C.
Nyob rau tib lub sij hawm, vim lub me me vapor siab ntawm tooj liab, nws yog ib qho yooj yim mus cais thaum distillation. Tsis tas li ntawd, tooj liab-calcium alloys uas muaj 60%-65% calcium muaj qhov ntom ntom dua (2.1-2.2g / cm³), uas tuaj yeem ua kom zoo delamination nrog cov electrolyte. Cov ntsiab lus calcium hauv cathode alloy yuav tsum tsis pub tshaj 62% -65%. Tam sim no efficiency yog li ntawm 70%. CaCl2 noj ib kilogram ntawm calcium yog 3.4-3.5 kilograms.
Cov tooj liab-calcium alloy uas ua los ntawm electrolysis yog raug rau txhua qhov distillation nyob rau hauv cov xwm txheej ntawm 0.01 Torr nqus tsev vacuum thiab 750-800 â ¢ qhov kub kom tshem tawm volatile impurities xws li poov tshuaj thiab sodium.
Tom qab ntawd qhov thib ob lub tshuab nqus tsev distillation yog nqa tawm ntawm 1050-1100 ° C, calcium yog condensed thiab crystallized nyob rau hauv sab sauv ntawm lub distillation tank, thiab cov residual tooj liab (muaj 10% -15% calcium) yog sab laug nyob rau hauv qab ntawm lub distillation. tank thiab rov qab mus rau electrolyzer siv.
Lub crystalline calcium tshem tawm yog muaj calcium uas muaj qib ntawm 98% -99%. Yog tias tag nrho cov ntsiab lus ntawm sodium thiab magnesium nyob rau hauv cov khoom siv raw CaCl2 tsawg dua 0.15%, cov tooj liab-calcium alloy tuaj yeem distilled ib zaug kom tau txais cov calcium uas muaj hlau nrog cov ntsiab lus ntawm ⺥ 99%.
High-purity calcium tuaj yeem tau txais los ntawm kev kho cov khoom siv calcium los ntawm lub tshuab nqus tsev distillation. Feem ntau, qhov ntsuas kub distillation yog 780-820 ° C, thiab lub tshuab nqus tsev yog 1 × 10-4. Kev kho distillation tsis tshua muaj txiaj ntsig rau kev ua kom huv chlorides hauv calcium.
Nitride tuaj yeem muab ntxiv rau hauv qab qhov ntsuas kub distillation los tsim ob lub ntsev hauv daim ntawv ntawm CanCloNp. Qhov ob ntsev no muaj qhov tsis tshua muaj vapor siab thiab tsis yooj yim volatile thiab tseem nyob rau hauv distillation residue.
Los ntawm kev ntxiv nitrogen tebchaw thiab purifying los ntawm lub tshuab nqus tsev distillation, cov sum ntawm impurity ntsiab chlorine, manganese, tooj liab, hlau, silicon, txhuas thiab npib tsib xee nyob rau hauv calcium yuav txo tau rau 1000-100ppm, thiab high-purity calcium ntawm 99.9% -99.99%. tuaj yeem tau.
Extruded los yog dov rau hauv pas nrig thiab daim hlau, los yog txiav rau hauv me me pieces thiab ntim rau hauv airtight ntim.
Raws li cov saum toj no peb txoj kev npaj, nws tuaj yeem pom tias txoj kev txo qis muaj cov txheej txheem thev naus laus zis yooj yim, siv lub zog tsawg thiab siv sijhawm tsawg dua, thiab tsim nyog rau kev tsim khoom lag luam.
Yog li ntawd, txoj kev txo qis yog txoj hauv kev tseem ceeb rau kev tsim cov Calcium Hlau hauv xyoo tas los no.
