Studies On Preparation Of Biomass Spices Vanillin And Methylphenyl Carbinol

With the shortage of the non-renewable resources, such as petroleum and coal, it has been an important issue for the reasonable utilization of biomass, and, the biomass spices have attracted a wide attention. Lignin as the second largest biomass resources, which is often discarded as industrial waste, caused waste of resources and environment pollution. Ionic liquids, known as green solvents, can catalyze lignin to obtain biomass spices vanillin. Biocatalysis with high efficiency, high selectivity, low toxicity and other characteristics, can catalyze to get biomass spices methylphenyl carbinol. In this study, biomass spices vanillin and methylphenyl carbinol were prepared. Ionic liquids including acidic and alkaline ionic liquids were used to catalyze the degradation of lignin, and, the vanillin was purified eventually. Biocatalysis method was used to catalyze the reduction of acetophenone to generate methylphenyl carbinol. Instead of fossil resources, biomass spices can bring better economic benefits, alleviate the shortage crisis of resources and reduce environmental pollution. The results are as follows:1. Three kinds of alkaline ionic liquids were prepared. Ionic liquids were used to degrade lignin, comparing with conventional NaOH, and the reaction process was detected by UV. As a result, BMIMOH has the best effect for lignin degradation. GC-MS analysis showed that the degradation products are mainly vanillin, guaiacol,4-hydroxy-3,5-dimethoxybenzaldehyde and other aromatic small molecules. The conditions for lignin degradation in presence of alkaline ionic liquid BMIMOH were optimized, and the optimal conditions were temperature 130 ?, reaction time 2 h, the ionic liquid concentration 0.15 mol/L, and re-treatment time 30 min.2. Eight kinds of acidic ionic liquid were prepared. Ionic liquid [C4SO3Hnhm]HSO4 has the best effect on lignin degradation by GC analysis. The conditions for lignin degradation in presence of acidic ionic liquid [C4SO3Hnhm]HSO4 were optimized, and the optimal conditions were reaction temperature 90 ?, reaction time 2 h, the ionic liquid concentration 0.075 mol/L, and the volume of water 60 mL. According to the standard curve of vanillin, vanillin can be obtained 0.07 g from 3 g lignin. The yield of vanillin with a purity of 99% was 1.73% by column chromatography purification.3. Different strains were explored to catalyze acetophenone to get methylphenyl carbinol, between which S. cerevisiae has highest efficiency for the reduction reaction. The Reaction conditions was optimized, and the optimal conditions were temperature 30 ?, reaction time 72 h, rotate speed 200 rpm and strain amount 8 g. The total yield of methylphenyl carbinol was 16% under the optimized conditions.