Qhov sib txawv tseem ceeb ntawm Raney npib tsib xee thiab npib tsib xee yog tias Raney npib tsib xee yog qhov sib xyaw ntawm ntau cov tshuaj lom neeg thaum npib tsib xee yog cov khoom siv tshuaj uas peb faib ua hlau.
Raney npib tsib xee yog ib lo lus paub zoo tias yog ib qho catalyst hauv cov tshuaj lom neeg sib xyaw ua ke. Txawm li cas los xij, npib tsib xee yog cov hlau thiab Raney npib tsib xee yog cov hmoov zoo uas muaj npib tsib xee ua cov khoom tseem ceeb.
Raney Nickel yog dab tsi?
Raney npib tsib xee yog cov hmoov zoo uas muaj cov nickel ua cov khoom tseem ceeb. Lub ntsiab lus ntawm qhov sib xyaw no yog "spongy nickel". Cov nickel nyob rau hauv cov ntaub ntawv no yog los ntawm nickel-aluminium alloys. Muaj ntau ntau qib ntawm Raney npib tsib xee, tab sis qhov ntau yog cov khoom grey. Qee qib ntawm cov khoom no yog pyrophoric. Qhov ntawd txhais tau tias; nws muaj peev xwm undergo ignition spontaneously. Peb siv cov khoom no feem ntau ua cua-ruaj khov slurries. Tus kws tshaj lij Asmeskas Murray Raney nrhiav tau cov khoom no.
Cov ntawv thov feem ntau ntawm cov khoom siv no yog ua raws li cov khoom siv. Ntxiv mus, nws yog qee zaum siv los ua cov tshuaj reagent hauv organic chemistry.
Production
Thaum xav txog kev tsim khoom ntawm Raney npib tsib xee, muaj ob kauj ruam raws li hauv qab no:
Alloy npaj
Ua ntej, peb yuav tsum npaj cov aluminium-nickel alloy. Peb tuaj yeem ua qhov no los ntawm kev yaj npib tsib xee hauv molten aluminium. Tom qab ntawd, peb yuav tsum tau txias (quench) cov tshuaj tiv thaiv sib tov. Thaum lub caij txias no, peb tuaj yeem ntxiv qee yam hlau xws li zinc lossis chromium. Qhov tseem ceeb, qhov sib ntxiv ntawm lwm cov hlau ua kom cov haujlwm ntawm cov catalyst tshwm sim. Yog li ntawd, peb hu cov khoom ntxiv no ua tus txhawb nqa.
Activation
Nyob rau hauv cov txheej txheem no, peb yuav tsum finely hmoov cov hlau. Tom qab ntawd peb yuav tsum tau kho cov hmoov ntawm cov hlau nrog cov concentrated sodium hydroxide tov. Nws muab sodium aluminate. Tom qab ntawd, peb yuav tsum tau tshem tawm aluminium li NiAl3 thiab Ni2Al3. Feem ntau ntawm cov nickel tseem nyob hauv daim ntawv ntawm NiAl. Tom qab ntawd peb tuaj yeem tshem tawm qhov seem ntawm sodium aluminate los ntawm kev ntxuav cov khoom nrog dej distilled.
Nickel yog dab tsi?
Nickel yog cov khoom siv tshuaj muaj lub cim Ni thiab tus lej atomic 28. Nws yog cov hlau nplaum uas muaj xim dawb-dawb. Nws yog tawv thiab ductile. Peb categorize no hlau raws li kev hloov hlau. Txij li cov txheej txheem oxide txheej npog cov hlau, npib tsib xee feem ntau tsis tshua muaj tshwm sim. Tab sis, yog hais tias peb finely hmoov cov hlau, qhov chaw saum npoo yuav nce, ua rau cov reactivity ntawm hlau thiab. Ntxiv mus, cov hlau no maj mam oxidized los ntawm oxygen; Yog li, peb xav tias nws yog cov hlau uas tiv taus corrosion.
Ntxiv mus, cov hlau no yog ferromagnetic ntawm chav tsev kub, uas yog tshwj xeeb rau plaub hlau, lwm tus yog hlau, cob alt thiab gadolinium. Lub melting point ntawm nickel yog 1455 ° C thaum lub boiling point yog 2730 ° C. Qhov feem ntau thiab ruaj khov oxidation xeev ntawm nickel yog +2. Cov tshuaj no kuj ua raws li lub hauv paus me me. Mohs hardness ntawm nickel yog 4.0.
Qhov txawv ntawm Raney Nickel thiab Nickel yog dab tsi?
Qhov sib txawv tseem ceeb ntawm Raney npib tsib xee thiab npib tsib xee yog tias Raney npib tsib xee yog qhov sib xyaw ntawm ntau cov tshuaj lom neeg thaum npib tsib xee yog cov khoom siv tshuaj uas peb faib ua cov hlau. Ntxiv mus, thaum xav txog cov tsos, Raney npib tsib xee tshwm raws li cov hmoov khoom hauv cov xim grey thaum npib tsib xee yog cov hlau nplaum nrog cov xim dawb-dawb. Yog li, qhov no kuj yog qhov sib txawv tseem ceeb ntawm Raney nickel thiab nickel. Tsis tas li ntawd, peb siv Raney npib tsib xee feem ntau ua cov catalyst thiab npib tsib xee ua cov hlau alloy.
Summary – Raney Nickel vs Nickel
Raney npib tsib xee yog cov hmoov zoo uas muaj npib tsib xee ua cov khoom tseem ceeb thaum npib tsib xee yog cov khoom siv tshuaj muaj lub cim Ni thiab tus lej atomic 28. Qhov sib txawv tseem ceeb ntawm Raney npib tsib xee thiab npib tsib xee yog Raney npib tsib xee yog sib xyaw ntawm ntau yam. chemical element, whereas npib tsib xee yog ib yam tshuaj uas peb categorize raws li ib tug hlau.
