Cov hlau molybdenum tshuav nws lub npe rau sab nraud zoo li molybdenum disulfide rau cov hlau lead - galena (lub npe Greek rau cov hlau lead yog molybdos).
Element discovery history
Nyob rau Hnub Nyoog Nruab Nrab hauv Tebchaws Europe, molybdenum tau hu ua peb cov zaub mov sib txawv, tab sis yuav luag zoo ib yam ntawm cov xim thiab cov qauv ntawm cov ntxhia - galena (Pbs), molybdenite (MoS 2) thiab graphite (C). Los ntawm txoj kev, cov pob zeb hauv av "molybdenum sheen" (lwm lub npe rau molybdenite) tau siv los ua cov xaum rau cov xaum uas tshuav xim ntsuab-grey rau ntawm daim ntawv.
Molybdenum hlau, 42 lub ntsiab lus ntawm lub sijhawm ntawm Mendeleev, suav tias yog qhov chaw yug ntawm Sweden. Nyob rau hauv 1758, tus kws tshuaj thiab mineralogist los ntawm lub teb chaws no, tus founder ntawm npib tsib xee, Axel Cronstedt, hais tias cov minerals saum toj no muaj ib tug txawv kiag li qhov. Ob xyoo caum tom qab, nws tus neeg ua haujlwm hauv tebchaws, kws tshuaj tshuaj los ntawm Köping, Karl Scheele, tau txais molybdic acid nyob rau hauv daim ntawv ntawm dawb precipitate ("dawb lub ntiaj teb") los ntawm boiling molybdenite nyob rau hauv concentrated nitric acid. Tus kws tshawb fawb intuitively nkag siab tias yog molybdic acid yog calcined nrog thee, ces nws muaj peev xwm cais tawm.hlau. Tsis muaj lub cub tawg tsim nyog, nws tau xa cov qauv mus rau Peter Gjelm, uas nyob rau xyoo 1782 cais cov hlau tshiab nrog ntau cov carbide impurities. Cov npoj yaig hu ua lub caij "molybdenum" (cov qauv hauv lub rooj zaum yog Mo).
Cov hlau ntshiab huv tsuas yog tau txais xyoo 1817 los ntawm Jens Berzelius, tus thawj tswj hwm ntawm Swedish Academy of Sciences.
Tus yam ntxwv ntawm cov khoom yooj yim
Txoj kev tsim khoom muaj txiaj ntsig zoo rau lub cev ntawm molybdenum thiab nws cov tsos. Hmoov hlau, blanks thiab rods ua ntej sintering - tsaus grey. Cov palette ntawm cov khoom tiav dov yog ntau nplua nuj - los ntawm yuav luag dub mus rau lub teeb nyiaj. Qhov ceev ntawm molybdenum yog 10.28 t / m 3. Cov hlau melts ntawm qhov kub ntawm 2623˚С, thiab ntawm 4639˚С nws boils. Ua tiav cov ntshiab molybdenum muaj zoo malleability thiab ductility, uas guarantees yooj yim dov thiab stamping. Lub workpiece nrog ib txoj kab uas hla mus txog 12 hli, txawm nyob rau hauv chav tsev kub, tuaj yeem khi dawb nrog ob lub pob los yog dov tawm mus rau ib daim ntawv nyias. Cov hlau muaj hluav taws xob zoo conductivity. Lub xub ntiag ntawm impurities tsub kom lub hardness thiab brittleness thiab loj txiav txim siab lub mechanical zog ntawm molybdenum.
Kev Sib Txuas Loj
Raws li ib feem ntawm cov tshuaj complex, lub caij nthuav tawm qhov sib txawv ntawm oxidation los ntawm +2 mus rau qhov siab tshaj plaws (cov tshuaj tom kawg yog qhov ruaj khov tshaj plaws), uas txiav txim siab cov khoom siv tshuaj molybdenum. Cov hlau no yog tus cwj pwm los ntawm cov tebchaw nrog oxygen thiab halogens (MoO3, MoCl5) thiab molybdates (cov ntsev ntawm molybdic acid). Cov tshuaj tiv thaiv oxidation tuaj yeem ua tau tsuas yog ntawm qhov kub thiab txias (ntawm 600˚С). Kev nce ntxiv yuav ua rau molybdenum cuam tshuam nrog carbon, phosphorus, thiab sulfur. Nws dissolves zoo nyob rau hauv nitric los yog rhuab sulfuric acid.
Phosphoric, arsenic, boric thiab silicic acids tsim cov tebchaw nrog molybdenum. Lub npe nrov tshaj plaws thiab nquag ntsev yog ammonium phosphomolybdate. Cov khoom uas muaj molybdenum yog qhov txawv ntawm cov xim palette thiab ntau qhov ntxoov ntxoo.
Molybdenum ore beneficiation technology
Kev lag luam tsim tawm ntawm cov ntshiab molybdenum tau ua tiav hauv xyoo pua 20th. Kev ua tshuaj lom neeg ntawm molybdenum ore yog ua ntej los ntawm nws cov txiaj ntsig: tom qab sib tsoo hauv crushers thiab pob zeb, txoj kev tseem ceeb yog tsib los yog rau flotation. Qhov tshwm sim yog qhov siab siab (txog 95%) ntawm molybdenum disulfide hauv cov khoom siv raw.
kauj ruam tom ntej thiab tseem ceeb tshaj plaws yog tua. Ntawm no undesirable impurities ntawm dej, sulfur, residues ntawm flotation reagents raug tshem tawm thiab molybdenum disulfide yog oxidized rau trioxide. Kev ntxuav ntxiv tuaj yeem ua tau ntau txoj hauv kev, tab sis cov hauv qab no yog cov nyiam tshaj plaws:
- ammonia txoj kev, nyob rau hauv uas molybdenum tebchaw yog yaj tag, thiab impurities raug tshem tawm;
- sublimation ntawm qhov kub ntawm 900 txog 1100 ˚С. Qhov tshwm sim - qhov concentration ntawm MoO3 nce mus rau 90-95%.
Kev lag luam tsim cov hlau molybdenum
Dhau hydrogen los ntawm kev ua kom huv si molybdenum trioxide (hauv chav kuaj rauKev txo qis feem ntau siv cov pa roj carbon lossis cov pa roj carbon monoxide, aluminium, silicon) tau cov hmoov hlau. Cov txheej txheem yuav siv sij hawm qhov chaw nyob rau hauv tshwj xeeb raj furnaces nrog ib tug maj mam nce nyob rau hauv kub ntawm 500 mus rau 1000 ˚С.
Cov txheej txheem saw rau kev tsim cov hlau molybdenum muaj xws li:
- nias. Cov txheej txheem yuav siv sij hawm qhov chaw nyob rau hauv steel pwm nyob rau hauv siab mus txog 300 MPa. Cov khoom sib txuas yog cov kua dej cawv ntawm glycerin. Qhov siab tshaj plaws ntawm qhov khoob (stabs) tsis pub tshaj 16 cm 2, thiab qhov ntev yog 600 cm. Rau qhov loj dua, cov ntaub ntawv roj hmab lossis polymer yog siv. Kev nias yuav tshwm sim hauv cov chav ua haujlwm uas cov kua tau txhaj rau hauv qhov siab.
- Sintering. Nws tshwm sim hauv ob theem. Thawj - qhov kub thiab txias, kav ntev li 30-180 feeb (nyob ntawm qhov loj ntawm lub workpiece), yog nqa tawm nyob rau hauv muffle furnaces nyob rau hauv ib tug hydrogen cua ntawm ib tug kub ntawm 1200 ˚С. Nyob rau theem thib ob (welding), lub workpiece yog rhuab mus rau qhov kub thiab txias ze rau lub melting point (2400-2500 ˚С). Yog li ntawd, qhov porosity txo qis thiab qhov ntom ntawm molybdenum nce.
Cov khoob loj uas hnyav txog 3 tons yog sintered hauv induction, electron beam lossis arc rauv. Cov txheej txheem ua tiav los ntawm kev ua haujlwm ntawm cov khoom siv sintered.
Ntau tshaj deposits
Molybdenum yog ib yam khoom uas tsis tshua muaj nyob hauv lub ntiaj teb lub pob zeb thiab hauv lub ntiaj teb tag nrho. Ntawm ob lub kaum os cov zaub mov uas muaj nyob hauv qhov, tsuas yog molybdenite yog qhov tseem ceeb ntawm kev lag luam.(MoS2). Nws cov peev txheej tsis muaj qhov kawg, thiab cov thev naus laus zis rau kev rho tawm cov hlau los ntawm powellites thiab molybdates twb tau tsim. Nyob ntawm seb cov ntxhia muaj pes tsawg leeg thiab cov duab ntawm lub cev ore, cov deposits muab faib ua cov leeg, leeg-tshuaj thiab skarn.
Cov pov thawj thoob ntiaj teb ntawm cov khoom muaj nqis txog 19 lab tons, nrog yuav luag ib nrab ntawm Tuam Tshoj. Txij li thaum xyoo 1924, qhov loj tshaj plaws molybdenum tso nyiaj yog Climax mine (USA, Colorado) nrog cov ntsiab lus nruab nrab txog li 0.4%. Feem ntau, kev rho tawm ntawm molybdenum ore yog ua nrog rau kev rho tawm ntawm tooj liab thiab tungsten.
Nyob rau hauv Russia, molybdenum reserves rau 360 txhiab tons. Ntawm 10 qhov kev tshawb nrhiav tso nyiaj, tsuas yog 7 tau tsim kev lag luam:
- Sorskoe thiab Agaskyrskoe (Khakassia);
- Bugdainskoe thiab Zhirekenskoe (Eastern Transbaikalia);
- Orekitkanskoe (Buryatia);
- Labash (Karelia);
- Tyrnyauz (Northern Caucasus).
Kev tsim khoom yog tsim los ntawm ob txoj hauv kev qhib thiab kaw.
Tus zais zais ntawm Samurai Swords
Tau ntau pua xyoo, European gunsmiths thiab cov kws tshawb fawb tau tawm tsam nrog qhov paub tsis meej ntawm qhov ntse thiab lub zog ntawm cov ntaj Nyij Pooj thaum ub los ntawm qhov pib ntawm lub xyoo pua thib ob, ua tsis tiav los ua cov riam phom zoo tib yam. Tsuas yog thaum kawg ntawm XΙX xyoo pua, tau tshawb pom molybdenum impurities hauv Japanese hlau, nws puas tuaj yeem daws qhov riddle no.
Thawj zaug, kev lag luam siv molybdenum ua cov khoom siv ntxiv los txhim kho cov hlau zoo (muab nws hardness thiab toughness) tau mastered hauv 1891 los ntawm Schneider& Co los ntawm Fabkis.
Kev Tsov Rog Thoob Ntiaj Teb thib ib tau ua haujlwm tseem ceeb rau kev txhim kho molybdenum metallurgy. Nws yog ib qho tseem ceeb uas lub thickness ntawm lub frontal armor ntawm lub Anglo-Fabkis tso tsheb hlau luam, yooj yim pierced los ntawm German plhaub ntawm tib caliber, raug txo los ntawm 75 hli mus rau 25 hli los ntawm kev ntxiv 1.5-2% molybdenum rau cov hlau ntawm armor daim hlau. Qhov no ua rau kom lub zog ntawm lub tshuab tau nce ntau.
Daim ntawv thov ntawm molybdenum
Ntau tshaj 80% ntawm tag nrho cov molybdenum siv hauv kev lag luam poob rau ferrous metallurgy. Yog tsis muaj nws, kev tsim cov cua sov-resistant cam khwb cia hlau, cov qauv thiab cov cuab yeej steels yog qhov xav tsis thoob. Ib qho hnyav ib feem ntawm lub caij txhim kho qhov zoo ntawm cov hlau yog sib npaug rau ob qhov hnyav ntawm tungsten. Txij li qhov ceev ntawm molybdenum yog ob zaug tsawg dua, nws cov alloys yog qhov zoo tshaj plaws rau tungsten alloys ntawm kev ua haujlwm kub hauv qab 1370 ˚С. Molybdenum steels qiv lawv tus kheej zoo dua rau carburizing.
Molybdenum yog nyob rau hauv kev thov hauv xov tooj cua-electronic, tshuaj thiab xim kev lag luam. Hauv kev siv tshuab engineering, nws yog siv los ua cov khoom siv cua sov. Hauv kev ua liaj ua teb, kev daws teeb meem tsis muaj zog ntawm cov ntsiab lus sib txuas ua rau txhim kho kev nqus ntawm cov as-ham los ntawm cov nroj tsuag. Nws yuav tsum tau nco ntsoov tias nyob rau hauv cov koob tshuaj loj, molybdenum muaj tshuaj lom rau cov kab mob nyob thiab cov nroj tsuag, thiab tsis zoo rau ib puag ncig.
Biological tseem ceeb
Hauv kev noj zaub mov ntawm tib neeg thiab tsiaj txhu, molybdenum yog ib qho tseem ceeb tshaj plaws ntawm kab. Nyob rau hauv daim ntawv ntawm ib tug active lom daim ntawv -molybdenum coenzyme - (Moco) yog qhov tsim nyog rau kev siv cov txheej txheem catabolic hauv cov ntaub so ntswg.
Kev tshawb fawb hauv thaj tsam ntawm kev tiv thaiv kab mob qog noj ntshav ntawm molybdenum zoo li pheej hmoo heev. Kev mob qog noj ntshav siab ntawm lub plab zom mov ntawm cov pej xeem hauv nroog Lin Xian (Honan Xeev, Tuam Tshoj) tau txo qis tom qab kev qhia txog cov ntxhia chiv uas muaj molybdenum rau hauv av.
Muaj tsawg zaus ntawm cov ntsiab lus tsis txaus hauv tib neeg lub cev, kev tsis sib haum xeeb ntawm lub hlwb, lub hlwb tsis zoo, kev puas siab puas ntsws thiab lwm yam kab mob loj heev tuaj yeem tsim. Qhov koob tshuaj molybdenum txhua hnub rau tus neeg laus yog los ntawm 100 txog 300 mcg. Thaum nws nce mus txog 5-15 mg, kev lom tshuaj lom yog kev zam, mus txog 50 mg - tuag. Cov nplua nuj nyob hauv molybdenum tshaj plaws yog nplooj zaub, cereals, legumes thiab berries (blackcurrant, gooseberry) cov qoob loo, cov khoom noj siv mis, qe, daim siab thiab ob lub raum ntawm cov tsiaj.
Ib puag ncig yam
Cov yam ntxwv lom neeg ntawm molybdenum ua rau muaj kev xav tau ntau ntxiv rau kev pov tseg pov tseg los ntawm kev ua cov khoom siv ore, nruj ua raws li cov txheej txheem thev naus laus zis ntawm kev lag luam kom tsis txhob muaj kev cuam tshuam tsis zoo rau kev noj qab haus huv ntawm cov neeg ua haujlwm thiab cov xwm txheej.
Txhua yam kev ntsuas yuav tsum tau ua los tiv thaiv kev nkag mus ntawm cov khoom lag luam ua tiav rau hauv av. Nws yuav tsum tau borne nyob rau hauv lub siab hais tias cov nroj tsuag muaj peev xwm nqus tau thiab sib sau molybdenum, yog li nws cov ntsiab lus nyob rau hauv tua thiab nplooj yuav ntau tshaj qhov tso cai concentrations. Qhov no ntsuab lojtej zaum yuav muaj kev phom sij rau tsiaj. Txhawm rau tiv thaiv cua los ntawm kev sib kis cov pob zeb siv, cov pob zeb pov tseg tau npog nrog ib txheej ntawm lub ntiaj teb.
Tshaj tawm hauv lub ntiaj teb molybdenum lag luam
Nrog rau qhov pib ntawm kev kub ntxhov nyiaj txiag thoob ntiaj teb, kev siv molybdenum thoob ntiaj teb poob los ntawm 9%. Qhov tshwj xeeb yog Tuam Tshoj, qhov twg muaj qhov nce mus txog 5%. Cov lus teb rau qhov poob qis hauv cov neeg siv khoom xav tau hauv xyoo 2009 yog qhov txo qis hauv cov khoom ntim. Nws muaj peev xwm mus txog qib dhau los ntawm cov zis tsuas yog tom qab plaub xyoos, thiab hauv 2014 qhov siab tshaj plaws tshiab ntawm 245 txhiab tons tau teeb tsa. Tuam Tshoj tseem yog cov neeg siv khoom loj thiab tsim cov molybdenum thiab nws cov khoom.
Molybdenum qhov ntom ntom thiab cov khoom zoo kawg nkaus tau ua rau nws tseem ceeb rau kev siv hlau thiab hlau uas yuav tsum muaj kev sib txuas ntawm lub teeb yuag, siab zog thiab corrosion kuj. Kev kwv yees kev loj hlob ntawm tus naj npawb ntawm cov chaw tsim hluav taws xob nuclear, lwm lub zog thiab cov chaw tsim khoom, kev tsim cov roj thiab roj tshiab hauv cov xwm txheej hnyav ntawm Far North thiab Arctic yuav inevitably ua rau muaj kev xav tau ntau ntxiv rau molybdenum thiab nws cov derivatives.
