Phosphoric corrosive (H3PO4) yog ib qho qhib tam sim ntawd thiab paub phosphorus hluavtaws nrog ntau yam kev siv niaj hnub. Txawm li cas los xij, kev hloov pauv mus rau qhov tseem ceeb txo qis tus kws kho mob hypophosphorous corrosive (H3PO2) tuaj yeem ua haujlwm nyuaj. Txawm hais tias muaj teeb meem, ob peb lub tswv yim kev sim tau tsim los xa cov tshuaj hypophosphorous corrosive uas muaj phosphoric corrosive ua cov khoom pib.
Ib qho kev siv tsis tu ncua muaj xws li kev txo qishypophosphorous acidcorrosive nrog tus kws tshaj lij txo qis, zoo li cov hlau hydride lossis sulfite compound. Piv txwv li, cov lus teb ntawm phosphoric corrosive nrog sodium hypophosphite (NaH2PO2) nyob rau hauv qhov pom ntawm ib qho impetus zoo li palladium los yog platinum tuaj yeem ua rau hypophosphorous corrosive. Ib txoj hauv kev ntxiv yog qhov sov so ntawm phosphoric corrosive, uas tuaj yeem ua tiav los ntawm kev ua kom sov ntawm qhov kub thiab txias.
Ntawm qhov tod tes, cov txheej txheem electrochemical tuaj yeem siv los hloov phosphoric corrosive rau hauv hypophosphorous corrosive. Electrolysis ntawm phosphoric corrosive siv cov khoom siv cathode tsim nyog, zoo li graphite lossis platinum, tuaj yeem ua haujlwm nrog kev sib cuam tshuam thiab tsim cov tshuaj hypophosphorous corrosive.
Tsis tas li ntawd, muaj cov txheej txheem uas siv cov kws paub txog kev txo qis, xws li formaldehyde lossis formic corrosive, hloov phosphoric corrosive rau hauv hypophosphorous corrosive. Cov tswv yim no feem ntau suav nrog cov lus teb ntau kauj ruam thiab yuav tsum tau ceev faj tswj cov lus teb.
Nws txhais tau hais tias me ntsis yuav tsum nco ntsoov tias kev tsim ntawm hypophosphorous corrosive los ntawm phosphoric corrosive yog tsim los ua tiav hauv kev tshawb fawb chaw ua haujlwm tsis zoo li niaj hnub no. Niaj hnub nimno creation tsis tu ncua suav nrog kev xaiv cov voj voog uas muaj txiaj ntsig thiab muaj txiaj ntsig.
Ua txhua yam rau hauv tus account, thaum hloov phosphoric corrosive tag nrho mus rau hypophosphorous corrosive muaj teeb meem, ob peb lub tswv yim lab tau tsim rau vim li no. Cov tswv yim no suav nrog kev siv cov kws tshaj lij txo qis, lub voj voog hluav taws xob hluav taws xob, lossis kev sib xyaw ntuj. Nyob rau hauv txhua rooj plaub, nws yog ib qho tseem ceeb rau kev xyaum ceeb toom thiab ua raws li cov kev cai ruaj ntseg tsim nyog thaum ua hauj lwm nrog cov khoom sib txuas.
Yuav ua li cas electrolytic txo phosphoric acid rau hypophosphorous acid?
Hypophosphorous acidyog ib txoj hauv kev los hloov phosphoric acid rau hauv nws. Aqueous H3PO4 yog electrolyzed kom tau ob lub electrons thiab tsim H3PO2:
H3PO4 + 2e- → H3PO2 + H2O
Qhov no electrolysis tuaj yeem ua tau nyob rau hauv ib lub cell sib faib nrog cov hlau lead cathode thiab platinum anode. Raws li phosphoric acid tau txo qis ntawm cathode, dej oxidation tshwm sim ntawm anode kom sib npaug cov tshuaj tiv thaiv.
Ob peb tsis xav tau optimization rau siab tshaj tawm los:
- Concentrated 85-90% H3PO4 yog nyiam los xyuas kom meej conductivity.
- Kub tswj tau nyob nruab nrab ntawm 60-80 degree los pab txo qis.
- Tam sim no qhov ceev ntawm 100-300 mA/cm2 muab cov txiaj ntsig zoo tshaj plaws.
- Lead yog tsim raws li inert cathode tab sis siab dua purity nickel cathodes txhim kho efficiency.
- Lub siab acidity yuav tsum muaj anode uas tiv thaiv corrosion, zoo li platinum.
Nrog ceev faj tswj, H3PO2 tawm los ib ncig ntawm 60-70% tuaj yeem tau electrochemically los ntawm phosphoric acid. Covhypophosphorous acidTom qab ntawd cais tawm ntawm catholyte los ntawm kev txias kom crystallize nws tawm.
Yuav ua li cas hlau txo phosphoric corrosive tag nrho rau hypophosphorous corrosive?
Qee cov hlau tuaj yeem txo cov phosphoric corrosive rau hypophosphorous corrosive los ntawm kev oxidized lawv tus kheej. Redox dynamic hlau zoo li zinc, hlau, thiab magnesium teb nrog concentrated H3PO4 los tsim H3PO2.
Piv txwv li, zinc hmoov thiab phosphoric corrosive teb raws li qhia los ntawm stoichiometry:
Zn + 2H3PO4 → Zn3(PO4)2 + H3PO2 + H2
Cov zinc mus txog raws li tus kws tshaj lij txo qis, tau txais oxidized rau zinc phosphate thaum phosphoric corrosive tau txo qis rau hypophosphorous corrosive. Kev sib piv reactivity tshwm sim nrog hlau hmoov.
Rau cov lus teb mus txuas ntxiv, ua kom sov siab 85% + H3PO4 rau 60-80 degree yog xav tau. H3PO2 tawm los yog qis ntawm ib ncig ntawm 30% vim yog cov lus teb sib txawv. Segregation los ntawm ib nrab crystallization yog teeb meem.
Txawm hais tias muaj qhov tsis zoo, kev siv cov hlau me me ua rau qhov no yog ib qho kev ua kom zoo tshaj plaws kom tau txais cov tshuaj hypophosphorous corrosive hauv chav kuaj yam tsis muaj electrolysis.
Yuav ua li cas hydriodic corrosive pab tsim hypophosphorous corrosive los ntawm phosphoric corrosive?
Cov kws kho mob txo qis xws li hydriodic corrosive (Hello) tuaj yeem txo cov phosphoric corrosive rau hypophosphorous corrosive raws li cov lus teb redox:
2HI + H3PO4 → H3PO2 + I2 + H2O
Txoj hauv kev no siv thaj chaw loj ntawm lub zog rau lub zog ntawm hydriodic corrosive kom tau txais cov hluav taws xob xav tau rau H3PO4 txo.
Tentatively, cov kev npaj siab ntawm Nyob Zoo thiab H3PO4 tau ua ke ua ib qho kev ua kom sov thiab ib puag ncig latent. Cov tsim iodine thiab dej yog refined tawm, tso cai seclusion ntawm H3PO2.
Liab phosphorus tuaj yeem sau rau hauv hydriodic corrosive hauv cov lus teb no. Liab P mus txog raws li tus kws tshaj lij txo qis.
Qhov nruab nrab acidic teb heev xav tau cov tais diav tshwj xeeb tseem tso cai tau txais H3PO2 hauv ib kauj ruam ib leeg. Yield enhancement nyob twj ywm ib qho kev sim.
Xaus
Thaum phosphoric corrosive tej zaum yuav tsis yog cov khoom pib zoo tshaj plaws rau hypophosphorous corrosive creation, ob peb txoj kev sim tau tsim los xa nws. Cov tswv yim no suav nrog electroreduction, hlau redox teb, lossis txo cov kws kho mob xws li hydroiodic corrosive (Nyob Zoo). Ua li ntawd, txhua lub tswv yim muaj nws qhov txwv txog kev tawm los, hloov pauv, thiab tshem tawm.
Hauv cov txheej txheem electroreduction, cov khoom siv cathode tsim nyog yog siv los ua haujlwm nrog kev txo qis ntawm phosphoric corrosive. Txoj hauv kev no tuaj yeem muab cov txiaj ntsig zoo ntawm hypophosphorous corrosive tab sis tsis tuaj yeem hloov kho rau qhov tsim loj loj vim tias muaj teeb meem kho vajtse.
Hlau redox cov lus teb yog ib qho txheej txheem ntxiv uas tuaj yeem siv los tsim hypophosphorous corrosive los ntawm phosphoric corrosive. Cov txheej txheem no suav nrog kev siv cov hlau tsis muaj zog, xws li palladium lossis platinum, kom txo cov phosphoric corrosive. Cov lus teb tuaj yeem sim ua kom yooj yim, ua rau tsis muaj txiaj ntsig zoo thiab teeb meem kev huv.
Txo cov kws tshaj lij zoo li nyob zoo tuaj yeem siv los hloov pauv phosphoric corrosive rau hauv hypophosphorous corrosive. Cov txheej txheem no yog me ntsis ncaj nraim thiab ua tau zoo, muab cov txiaj ntsig zoo dua sib piv nrog cov tswv yim sib txawv. Txawm li cas los xij, kev soj ntsuam nrog Howdy tuaj yeem muaj kev pheej hmoo, yuav tsum tau ceev faj txog kev tiv thaiv kev nyab xeeb.
Txawm hais tias cov kev txwv no, cov txheej txheem kev tshawb fawb no muab qhov tseem ceeb txwv tsis pub nkag mus rau hypophosphorous corrosive yam tsis tas yuav tsum tau ua rau cov voj voog niaj hnub nyuaj. Los ntawm kev ua haujlwm ntawm kev tsim khoom thiab kev kho mob ntawm cov tswv yim no, kev siv hluav taws xob tsim hluav taws xob ntawm H3PO4 kom tau txais kev pab phosphorus intensifies zoo li H3PO2 tuaj yeem txuas ntxiv.
Txhawm rau ua kom tiav lub hom phiaj no, kev tshawb nrhiav ntxiv txog kev txhim kho cov lus teb, cov txheej txheem ntxuav, thiab ntau yam yog qhov tseem ceeb. Tsis tas li ntawd, tsim kom muaj kev ruaj ntseg thiab kev lag luam ntau dua rau kev sib koom ua ke phosphorus tebchaw rau hauv cov ntawv thov sib txawv yog qhov tseem ceeb rau kev txhawb nqa lub teb.
Tag nrho hauv tag nrho, thaum lub chaw sim npaj ntawm hypophosphorous corrosive los ntawm phosphoric corrosive muaj teeb meem, cov tswv yim sib txawv tau tsim kom tau mus rau nws. Txhua cov txheej txheem muaj nws qhov txwv, txawm li cas los xij lawv muab kev nkag siab tseem ceeb rau hauv kev tsim hluav taws xob ntawm H3PO4. Kev tshawb nrhiav ntxiv thiab kev txhim kho tuaj yeem ua rau muaj kev txawj ntse thiab ua tau zoo rau kev sib xyaw ua ke ntawm phosphorus compound.
Cov ntaub ntawv
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