亚/超临界水-乙醇体系中煤与杜氏盐藻共液化制备液体燃料

Production of liquid fuel via co-liquefaction of coal and Dunaliella tertiolecta in sub/supercritical water-ethanol system

在间歇式高温高压反应釜中,对亚/超临界水-乙醇体系中煤和杜氏盐藻共液化制备液体燃料进行了研究。考察了水-乙醇介质中乙醇质量分数、反应温度、料液比和反应时间等对共液化效果的影响,通过FT-IR和GC-MS等分析方法对液化产物进行了分析。研究结果表明:当亚/超临界水-乙醇介质中乙醇质量分数为60%,反应温度为360℃,料液比为1∶10,反应时间为30 min时,所得液体燃料的产率和转化率分别为40.29%和70.62%。FT-IR分析结果表明,在亚/超临界水-乙醇体系下,煤和杜氏盐藻中各主要成分均得到了有效转化。GC-MS分析结果说明,液体燃料中的乙酯类物质较多,这主要是因为乙醇与液化产物中的酸类物质发生了酯化反应。由此说明,杜氏盐藻的加入,显著的促进了煤的液化,提升了液体燃料的产率和转化率,同时也提高了液体燃料的品质,为煤的清洁化利用提供了理论基础。

The co-liquefaction of coal and Dunaliella tertiolecta （D. tertiolecta） with sub/supercritical water-ethanol as the reaction medium is investigated in a batch autoclave under high temperature and high pressure. The effects of reaction conditions such as volume fraction of ethanol to water, reaction temperature, ratio of feedstock/solvent and reaction time on the co-liquefaction rate are studied. The produced liquid fuel is analyzed with FT-IR and GC-MS. The experimental results show that the liquid fuel yield and conversion in the co-liquefaction are 40. 29% and 70. 62% , respectively,under the following conditions： 60% （volume fraction） of ethanol, 360~C of reaction temperature, 30 minutes of reaction time and 1 ： 10 of the ratio of feedstock/solvent. FT-IR analysis results show that the main components of coal and D. tertiolecta could be liquefied effectively in the sub/supercritical water-ethanol medium. The GC-MS analysis results indicate that there is more carboxylic acid ethyl ester in the liquid fuel, which is mainly because of the esterification reaction between acids and ethanol in the co-liquefaction. Thereby, the addition of D. tertiolecta can significantly promote the coal liquefaction. The liquid fuel yield, conversion and the quality of liquid fuel have been improved, which provides a theoretical basis and practical significance for the clean utilization of coal.