Dimethyl carbonate yog ib qho tseem ceeb organic compound dav siv hauv kev lag luam tshuaj, tshuaj, hluav taws xob thiab lwm yam lag luam. Kab lus no yuav qhia txog cov txheej txheem tsim khoom thiab kev npaj ntawm dimethyl carbonate.

1, Kev tsim cov txheej txheem ntawm dimethyl carbonate

Cov txheej txheem ntau lawm ntawm dimethyl carbonate tuaj yeem muab faib ua ob hom: chemical method thiab lub cev txoj kev.

1) Cov txheej txheem tshuaj

Cov tshuaj synthesis tshuaj sib npaug ntawm dimethyl carbonate yog: CH3OH + CO2 → CH3OCO2CH3

Methanol yog cov khoom siv raw rau dimethyl carbonate, thiab carbonate gas yog cov reactant. Cov txheej txheem tshuaj tiv thaiv yuav tsum muaj cov catalyst.

Muaj ntau yam catalysts, suav nrog sodium hydroxide, calcium oxide, tooj liab oxide, thiab carbonate. Carbonate ester muaj qhov zoo tshaj plaws catalytic nyhuv, tab sis kev xaiv ntawm catalyst kuj yuav tsum tau xav txog tej yam xws li nqi thiab ib puag ncig.

Cov txheej txheem ntau lawm ntawm dimethyl carbonate feem ntau suav nrog cov kauj ruam xws li methanol purification, oxygen oxidation, cua sov cov tshuaj tiv thaiv, kev sib cais / distillation, thiab lwm yam. Thaum lub sij hawm cov txheej txheem tshuaj tiv thaiv, nruj tswj ntawm tsis xws li kub, siab, thiab cov tshuaj tiv thaiv lub sij hawm yuav tsum tau los txhim kho yield thiab kev huv.

2) Lub cev txoj kev

Muaj ob txoj hauv kev lub cev tseem ceeb rau kev tsim cov dimethyl carbonate: txoj kev nqus thiab compression txoj kev.

Txoj kev nqus dej siv methanol ua ib qho nqus thiab ua rau cov CO2 ntawm qhov kub thiab txias los tsim dimethyl carbonate. Cov absorbent tuaj yeem rov qab siv tau, thiab cov pa roj carbon dioxide tsim los ntawm cov tshuaj tiv thaiv kuj tuaj yeem siv dua, tab sis cov tshuaj tiv thaiv qeeb thiab lub zog noj yog siab.

Txoj cai compression siv lub cev muaj zog ntawm CO2 los rau hauv kev sib cuag nrog methanol nyob rau hauv siab, yog li ua tiav cov kev npaj ntawm dimethyl carbonate. Txoj kev no muaj cov tshuaj tiv thaiv sai, tab sis yuav tsum muaj cov khoom siv hluav taws xob compression siab thiab raug nqi ntau.

Ob txoj kev saum toj no muaj lawv tus kheej qhov zoo thiab qhov tsis zoo, thiab tuaj yeem xaiv raws li kev xav tau ntawm daim ntawv thov thiab kev lag luam.

2, Kev npaj ntawm dimethyl carbonate

Muaj ntau txoj hauv kev los npaj cov dimethyl carbonate, thiab cov hauv qab no yog ob txoj kev siv ntau:

1) Methanol txoj kev

Qhov no yog txoj kev siv ntau tshaj plaws rau kev npaj dimethyl carbonate. Cov kauj ruam ua haujlwm tshwj xeeb yog raws li hauv qab no:

(1) Ntxiv methanol thiab potassium carbonate / sodium carbonate, thiab cua sov rau cov tshuaj tiv thaiv kub thaum nplawm;

(2) Maj mam ntxiv CO2, txuas ntxiv nplawm, thiab txias tom qab cov tshuaj tiv thaiv tiav;

(3) Siv ib qho kev sib cais los cais cov sib tov thiab tau txais dimethyl carbonate.

Nws yuav tsum tau muab sau tseg tias qhov kub thiab txias, siab, lub sij hawm tshuaj tiv thaiv, raws li zoo raws li hom thiab tus nqi ntawm catalyst yuav tsum tau tswj thaum lub sij hawm cov tshuaj tiv thaiv txheej txheem los txhim kho yield thiab purity.

2) Oxygen oxidation txoj kev

Ntxiv nrog rau txoj kev methanol, txoj kev oxygen oxidation kuj tseem siv rau kev npaj ntawm dimethyl carbonate. Txoj kev no yooj yim rau kev khiav lag luam thiab tuaj yeem ua tiav kev tsim khoom tas mus li.

Cov kauj ruam ua haujlwm tshwj xeeb yog raws li hauv qab no:

(1) Ntxiv methanol thiab catalyst, tshav kub rau cov tshuaj tiv thaiv kub thaum nplawm;

(2) Ntxiv cov pa oxygen rau cov tshuaj tiv thaiv kab mob thiab txuas ntxiv nplawm;

(3) Sib cais, distilled, thiab purify cov tshuaj tiv thaiv sib tov kom tau dimethyl carbonate.

Nws yuav tsum tau muab sau tseg tias cov pa oxidation txoj kev yuav tsum tau tswj tsis xws li tus nqi mov thiab cov tshuaj tiv thaiv kub ntawm cov pa roj, raws li zoo raws li cov kev faib ua feem ntawm cov tshuaj tiv thaiv Cheebtsam, los txhim kho yield thiab purity.

Los ntawm kev qhia txog kab lus no, peb tuaj yeem kawm txog cov txheej txheem tsim khoom thiab kev npaj ntawm dimethyl carbonate. Los ntawm cov qauv molecular mus rau cov lus piav qhia ntxaws txog cov txheej txheem tshuaj tiv thaiv thiab cov txheej txheem tsim khoom, peb tau muab cov txheej txheem kev paub dav dav thiab raug. Kuv vam tias tsab xov xwm no tuaj yeem txhawb cov neeg nyeem kev kawm thiab tshawb fawb hauv daim teb no.