Lub luag haujlwm tseem ceeb ntawm Sodium Hydroxide hauv Kev Lag Luam Metallurgical

Hauv kev lag luam hlau loj thiab nyuaj , sodium hydroxide (NaOH), feem ntau hu ua caustic soda lossis lye, ua lub luag haujlwm ntau yam thiab tsis tseem ceeb. Cov tshuaj alkaline muaj zog no, muaj nyob rau hauv cov khoom khov (xws li flake lossis granular) thiab cov kua, yog tus neeg ua si tseem ceeb hauv ntau yam txheej txheem hlau, los ntawm kev rho tawm cov hlau los ntawm lawv cov ores mus rau qhov kawg ntawm cov khoom hlau.

1. Ore Processing thiab Extraction

1.1 Hloov mus rau Soluble ntsev

Ib qho ntawm cov haujlwm tseem ceeb ntawm sodium hydroxide hauv metallurgy yog hloov cov khoom muaj nqis hauv cov ores mus rau hauv cov ntsev soluble. Qhov no yog qhov tseem ceeb vim nws ua rau muaj kev sib cais ntawm cov hlau xav tau los ntawm cov khoom tsis muaj kuab lom uas muaj nyob hauv cov ore. Piv txwv li, hauv kev rho tawm ntawm tungsten, cov txheej txheem pib nrog kev ci cov tungsten - bearing ore, zoo li scheelite lossis wolframite, nrog sodium hydroxide lossis sodium Carbonate . Cov txheej txheem ci no hloov cov tungsten minerals mus rau hauv soluble sodium tungstate. Cov soluble sodium tungstate tuaj yeem ua tiav ntxiv, sib cais los ntawm cov khoom seem insoluble, thiab thaum kawg hloov rov qab mus rau hauv tungsten ntshiab los ntawm cov tshuaj tiv thaiv tom qab.

1.2 Cov txheej txheem Leaching

Sodium hydroxide kuj tseem siv rau hauv cov txheej txheem leaching. Rau qee cov hlau ore, leaching nrog sodium hydroxide daws tuaj yeem xaiv cov txiaj ntsig ntawm cov hlau. Qhov no yog tshwj xeeb tshaj yog muaj feem xyuam rau cov qib qis los yog complex ores uas ib txwm smelting txoj kev yuav tsis raug nqi - zoo. Hauv kev rho tawm ntawm txhuas los ntawm bauxite ore ntawm Bayer txheej txheem, sodium hydroxide yog siv los tshem tawm alumina. Bauxite muaj impurities xws li hlau oxides, silica, thiab titanium dioxide. Thaum bauxite raug kho nrog kub, concentrated sodium hydroxide tov, lub alumina reacts tsim soluble sodium aluminate, thaum feem ntau ntawm cov impurities tseem insoluble thiab yuav raug cais los ntawm pom.

2. Hlau Refining

2.1 Tshem tawm cov impurities

Thaum lub sijhawm ua kom cov hlau zoo , sodium hydroxide ua haujlwm ua tus neeg sawv cev muaj zog rau kev tshem tawm ntau yam tsis huv ntawm cov hlau. Nws tuaj yeem ua rau muaj kev cuam tshuam nrog oxides, sulfides, thiab lwm yam tsis huv uas tsis yog hlau uas muaj nyob rau ntawm qhov chaw lossis hauv cov hlau matrix. Hauv kev ua kom tooj liab zoo, piv txwv li, sodium hydroxide tuaj yeem siv los tshem tawm cov tsis huv ntawm tooj liab oxide. Thaum tooj liab nrog cov tsis huv ntawm oxide raug kho nrog sodium hydroxide, qhov kev ua haujlwm redox tshwm sim. Cov hydroxide ions txo cov tooj liab oxide rau cov tooj liab hlau, thiab tib lub sijhawm, tsim cov ntsev sodium soluble nrog lwm cov tsis huv uas tsis yog hlau, uas tom qab ntawd tuaj yeem tshem tawm yooj yim. Cov txheej txheem no pab txhim kho qhov huv thiab zoo ntawm tooj liab, txhim kho nws cov hluav taws xob conductivity thiab cov khoom siv kho tshuab.

2.2 Kev them nyiaj yug Electrolytic Refining

Hauv cov txheej txheem electrolytic refining, sodium hydroxide tuaj yeem ua lub luag haujlwm hauv kev tswj xyuas qhov ruaj khov ntawm electrolyte thiab ua kom yooj yim rau kev tso tawm ntawm cov hlau ntshiab ntawm cathode. Rau qee cov hlau, xws li zinc, hauv alkaline electroplating da dej, sodium hydroxide yog siv los ua ib tus neeg sawv cev thiab cov ntsev ntsev. Nws complexes nrog zinc ions los tsim zincate ions, uas yuav pab kom lub plating da dej ruaj khov thiab txhim kho lub da dej conductivity. Qhov no ua rau muaj qhov sib txawv ntau dua ntawm zinc ntawm cov cathode, ua rau muaj qhov zoo dua - zoo zinc txheej.

3. Kev kho deg

3.1 Degreasing thiab ntxuav

Cov hlau nplaum feem ntau muaj cov kab mob xws li roj, roj, thiab cov organic residues uas yuav tsum tau muab tshem tawm ua ntej ua haujlwm ntxiv. Sodium hydroxide yog ib qho tshuaj degreasing zoo. Nws reacts nrog esters ntawm fatty acids uas muaj nyob rau hauv cov roj thiab roj los ntawm ib tug txheej txheem hu ua saponification. Piv txwv li, thaum stearic acid esters hauv cov roj zaub teb nrog sodium hydroxide, lawv tsim dej - soluble sodium stearate, feem ntau hu ua xab npum, thiab glycerol. Qhov no ua rau nws muaj peev xwm ntxuav cov pa paug nrog dej, tawm hauv cov hlau huv. Cov txheej txheem ntxuav no yog qhov tseem ceeb rau kev ua haujlwm tom ntej xws li electroplating, pleev xim, lossis vuam, vim tias qhov chaw huv si ua kom zoo dua adhesion ntawm cov coatings lossis cov ntawv cog lus muaj zog.

3.2 Etching thiab Surface Preparation

Sodium hydroxide kuj tseem siv rau hauv cov txheej txheem etching hlau. Rau txhuas thiab nws cov alloys, sodium hydroxide yog dav siv rau alkali etching, feem ntau ua ua ntej anodizing lossis lwm yam kev kho saum npoo . Kev etching nrog sodium hydroxide tsim cov qauv nto sib xws thiab huv si ntawm cov hlau txhuas, ua rau thaj chaw nto ntau dua thiab txhim kho qhov lo rau ntawm cov txheej tom ntej. Tus nqi ntawm etching tuaj yeem tswj tau los ntawm kev kho qhov concentration ntawm sodium hydroxide, qhov kub, thiab lub sijhawm ntawm kev raug.

4. Desulfurization hauv hlau thiab lwm yam hlau ntau lawm

Hauv kev tsim cov hlau thiab lwm yam hlau, sulfur yog ib qho tsis zoo rau impurity vim nws tuaj yeem ua rau brittleness hauv cov hlau, txo nws cov khoom siv kho tshuab thiab weldability. Sodium hydroxide tuaj yeem siv los ua tus neeg sawv cev desulfurizing. Hauv cov hlau - ua cov txheej txheem, thaum sodium hydroxide ntxiv rau cov hlau molten, nws reacts nrog sulfur los ua sodium sulfide. Cov sodium sulfide tsim yog tsawg soluble nyob rau hauv cov hlau molten thiab tuaj yeem raug tshem tawm los ntawm kev ua haujlwm slagging. Qhov no yuav pab txhim kho qhov zoo ntawm cov hlau thiab lwm yam hlau los ntawm kev txo cov sulfur cov ntsiab lus kom tau txais qib.

5. Lub luag haujlwm hauv cov txheej txheem Electrochemical

5.1 Electrolysis ntawm Aluminium

Hauv kev lag luam txhuas niaj hnub no, Hall - Héroult txheej txheem, thawj txoj hauv kev tsim cov txhuas, tso siab rau lub tshuab electrolyte. Txawm hais tias lub ntsiab electrolyte yog ib qho sib xyaw ntawm cryolite thiab alumina, sodium hydroxide tuaj yeem tshwm sim me me hauv qee qhov kev hloov pauv ntawm cov txheej txheem lossis hauv cov theem ua ntej kho. Sodium hydroxide tuaj yeem cuam tshuam cov hluav taws xob conductivity thiab tshuaj lom neeg tshwm sim ntawm cov electrodes. Nws pab txhawb kev khiav ntawm tam sim no los ntawm electrolyte, uas yog ib qho tseem ceeb rau decomposition ntawm alumina rau hauv txhuas thiab oxygen ntawm cathode thiab anode raws.

5.2 Lwm yam Electrochemical Hlau Deposition thiab rov qab

Sodium hydroxide kuj tseem siv rau hauv qee cov txheej txheem electrochemical rau hlau deposition thiab rov qab. Piv txwv li, hauv electrodeposition ntawm qee cov hlau los ntawm lawv cov kev daws teeb meem, sodium hydroxide tuaj yeem siv los kho pH ntawm cov tshuaj electrolyte. Qhov kev hloov pauv pH no tuaj yeem muaj kev cuam tshuam loj rau cov tshuaj tiv thaiv electrochemical, cuam tshuam cov yam ntxwv xws li tus nqi ntawm cov hlau deposition, qhov zoo ntawm cov hlau deposited txheej, thiab kev xaiv ntawm hlau deposition thaum muaj ntau yam hlau ions nyob rau hauv cov tshuaj.

Xaus lus, sodium hydroxide yog ib yam tshuaj tseem ceeb hauv kev lag luam metallurgical. Nws cov ntawv thov ntau yam hauv kev ua cov hlau , kev ua kom cov hlau zoo, kev kho qhov chaw, desulfurization, thiab cov txheej txheem electrochemical pab txhawb rau kev tsim cov hlau zoo thiab cov khoom siv hlau. Raws li kev lag luam metallurgical txuas ntxiv hloov zuj zus, lub luag haujlwm ntawm sodium hydroxide yuav tseem ceeb heev, nrog rau kev tshawb fawb thiab kev txhim kho txuas ntxiv tsom mus rau kev ua kom zoo dua nws siv thiab tshawb nrhiav cov ntawv thov tshiab los txhim kho kev ua haujlwm zoo thiab txo qhov cuam tshuam rau ib puag ncig.