工业木质素预处理及催化转化苯酚

Pretreatment of industrial lignin and catalytic conversion into phenol

摘要:

传统化石能源日益枯竭以及环境污染压力日益加大使得开发以生物质为代表的可替代能源迫在眉睫，木质素作为仅次于纤维素的生物质中第二大主要成分用来制备高附加值化学品是提高生物质资源利用效率的关键。本文将工业木质素进行预处理后采用双液相反应体系将工业木质素转化为苯酚等化合物，使用微波辐照代替传统的加热，考察了预处理方式、温度、时间等条件对产物收率的影响。结果表明，以1-甲基-3-乙基咪唑醋酸盐 ([EMIM]OAc) 处理的工业木质素在微波反应器输出功率为400 w、反应温度为90 ℃、催化剂为1-甲基-3-胺乙基咪唑四氟硼酸盐 ([AEMIM]BF4) 双液相反应体系中反应60 min苯酚的收率最高可达8.14%。

Abstract:

Recent concerns about the gradual depletion of conventional fossil resources and the pressure from global climate change have accentuated the need for new alternative feedstock. As one of the main components in biomass, lignin is the second most abundant natural polymer after cellulose, and has the potential to serve as a sustainable source of energy and organic carbon to replace petroleum-based chemicals. Efficient conversion of?lignin?into?high value-added chemicals is crucial to improve the economic feasibility of biomass refinery.?In the present study, several pretreatment technologies on industrial lignin were carried out to enhance phenol production. A microwave irradiation assisted biphasic reaction system was used to convert pretreated industrial lignin into phenolic compounds. Lignin conversion, reaction temperature, time and pretreatment method, were optimized.?The highest phenol yield was 8.14%?obtained from lignin pretreated by 1- ethyl -3-methylimidazolium acetate at 400 W for 60 min in a biophasic system catalyze by 1-aminoethyl-3-methylimidazolium tetrafluoroborate.