碳基固体酸催化生物油酯化降酸工艺参数优化  

Optimization of process parameters on carbon-based solid acid catalyzing bio-oil esterification for reducing acidity

作　　者：谭文英[1] 程晓红 王述洋[2] 李建顺 

机构地区：[1]东北林业大学材料科学与工程学院,哈尔滨150040 [2]东北林业大学机电工程学院,哈尔滨150040

出　　处：《农业工程学报》2018年第3期227-233,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家863高科技发展计划课题(2007AA05Z414);南京领军型科技创业人才引进计划资助(1007012)

摘　　要：为了降低生物油中羧酸类物质的质量分数,提高生物油品质,本试验采用碳基固体酸作为催化剂,对生物油进行催化酯化降酸提质。以乙酸为模型与甲醇反应,用单因素和响应面法优化生物油催化酯化反应条件,得出最佳工艺参数:反应温度100℃、醇酸比3.37、反应时间2.49 h、催化剂质量分数为5.26%,乙酸平均转化率为94.72%,在此条件下,分别用甲醇、乙醇、正丁醇与生物油进行催化酯化反应。结果表明:酯化后生物油中羧酸类物质转化成酯,酸值降低了82.82%~91.41%,降酸效果明显。且酯化后,生物油的密度降低、黏度减小、热值增加,提高了生物油作为燃料的品质。本研究可为生物油降酸提质提供参考依据。As an ideal clean energy, biomass is friendly to the environment. Bio-oil is a brown and black viscous liquid obtained by rapid pyrolysis of biomass under anoxic conditions. As a kind of liquid fuel, it has the disadvantages of high acid value, high water content, high viscosity and low calorific value. In addition, bio-oil is the mixture of hundreds of chemicals. Carboxylic acids enhance corrosion resistance of bio-oil. Amounts of water reduce the calorific value of the bio-oil. Aldehydes and other labile compounds make the bio-oil coking or polymerize easily during storage, with the increased viscosity, affecting the quality of the bio-oil. In this experiment, in order to reduce the content of carboxylic acid in bio-oil, the carbon-based solid acid catalysts were used to catalyze esterification of bio-oil. In the experiment, 4 kinds of carbon-based solid acid catalysts were prepared by incomplete carbonization and carbonization-sulfonation. They were starch-Ts OH, sucrose-Ts OH, glucose-TsO H and corn flour-sulfuric acid. The catalysts were characterized by FTIR（Fourier transform infrared spectroscopy）, indicating that the carbon-based solid acid catalyst is an aromatic carbon compound with sulfonic groups. Esterification was carried out with acid and alcohol as model compounds. Among the 4 catalysts, starch-TsO H had the highest esterification rate, and the conversion of acetic acid reached 91.58%. The effects of reaction temperature, reaction time, catalyst mass fraction and ratio of alcohol to acid on the conversion of acetic acid were investigated by single factor experiment. Response surface methodology was used to optimize the catalytic esterification conditions of the bio-oil model compound. The optimum reaction conditions were as follows： reaction temperature 100 ℃, alkyd ratio 3.37, reaction time 2.49 h, and catalyst mass fraction 5.26%, and the acetic acid conversion rate reached 95.51%. Under these conditions, 3 validation experiments were carried out, the conversion rates were 94.89%, 94.26%

关 键 词：催化剂 生物质 燃料 生物油 催化酯化 

分 类 号：TK6[动力工程及工程热物理—生物能]