Synthesis Of Ionic Liquid [AMIM]Cl And Its Application For Separation Of Cellulose In Corn Cob

Corn cob is a cheap and widely available agricultural by-products. In most ofcountry, corn cob is often incinerated, which is a waste of resources and leads toenvironmental pollution. Corn cob is an important verwertbar resource, which morethan70%of component is cellulose and hemicellulose. This article throughsynthetize green solvent [AMIM]Cl (1-allyl-3-methylimidazolium chloride), to achieveeffective detachment of cellulose and hemicellulose in the corn cob and discussed thecellulose dissolved condition in [AMIM]Cl and enzymatic hydrolysis conditions ofregenerated cellulose. The main content is as follows:Firstly, through single factor and orthogonal experiments, the optimal conditionsof synthetize green solvents [AMIM]Cl through allyl chloride and1-methylimidazolereaction were obtained: reaction temperature60℃, reaction time10h, allyl chlorideand1-methylimidazole molar ratio1:1.4. At this point,[AMIM]Cl yield up to92.18%.FT-IR, NMR analysis revealed that the product [AMIM]Cl, thermal gravimetricanalysis obtained decomposition temperature is272.38℃.[AMIM]Cl showedexcellent solubility for microcrystalline cellulose and corn cob cellulose, Along withthe increase of reaction temperature and time, The solubility of cellulose increasinglylarge. The solubility of microcrystalline cellulose reached9.5%, through heating andstirring1h at100℃. But corn cob cellulose solubility was6%. FT-IR showed that thestructural of cellulose have no difference, before and after dissolution. It was only adirect physical dissolution and no derivative groups generated.Secondly, the optimal condition of removal corn cob lignin was studied by singlefactor and orthogonal experiment. The result shows that: sodium hydroxideconcentration2%, treatment time90min, corn cob aqueous ratio1:20, treatmenttemperature115℃.This point, the lignin removal rate reached62.49%. Throughstudying on the effects of reaction temperature, reaction time, the volume ofprecipitator on separation corn cob cellulose by [AMIM]Cl. The results showed that:the separation temperature should between90℃and110℃, solution time70min, thevolume of precipitator was60mL, the cellulose solubility up to18.5%. FT-IR resultsdisplayed that Characteristic infrared absorption peaks of the extract product was the same as microcrystalline cellulose.Thirdly, by single factor and orthogonal test, The optimize saccharificationconditions of corn cob material as follows: temperature50℃, the addition of cellulase720U, pH4.8, substrate concentration100g/L, time72h, At this moment the maximumenzymatic hydrolysis rate was13.08%. Corn cob was pretreatment by1.0%sulfuricacid,1.5%sodium hydroxide,3.0%hydrogen peroxide, alkaline hydrogen peroxide(sodium hydroxide1.5%) respectively, cellulose enzymatic hydrolysis rate was28.04%,38.29%,20%,46.08%. However,[AMIM]Cl regenerated cellulose was57.68%.