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农作物秸秆和林业废弃物是资源量大、可再生的非粮生物质。它们由半纤维素、纤维素和木质素组成,源于这些生物质的单糖不仅可以经过生物催化过程制备纤维乙醇,还是化学催化法制备传统烃类运输燃料的重要平台。本文首先介绍了木质生物质酶法和酸催化法水解制备单糖的工艺特点,然后详细介绍了近几年来开发的从单糖出发制取烃类生物燃料的各种新型催化方法,如单糖经HZSM-5分子筛直接催化重整制备液体烃类,以及单糖经乙酰丙酸和酯化加氢工艺、经多元醇和水相脱水加氢(APD/H)工艺、经糠醛类化合物和羟醛缩合加氢工艺、经单官能团化合物和催化提质工艺。对这些催化方法的工艺条件、催化剂组成和化学反应进行了总结评述。考虑到由单糖制备C6以上烃类可以直接或混配为传统的液体燃料,本文对这两条工艺路线进行了重点介绍,总结了过程所发生的反应和脱氧机理,并探讨了工业化过程中需要注意的科学难题。
Crop straws and forestry waste are large, renewable, non-food biomass. They are composed of hemicelluloses, cellulose and lignin. Monosaccharides derived from these biomass can not only be used to prepare cellulosic ethanol through biocatalysis, but also be an important platform for the preparation of traditional hydrocarbon transportation fuels by chemical catalysis. In this paper, the process characteristics of the monosaccharides prepared by enzymatic hydrolysis of woody biomass and acid-catalyzed hydrolysis were introduced. Then, various new catalytic methods for preparing hydrocarbon biofuels from monosaccharides, such as monosaccharides Direct catalytic reforming of HZSM-5 zeolite to prepare liquid hydrocarbons, and monosaccharides by levulinic acid and esterification hydrogenation process, the polyol and aqueous phase dehydration and hydrogenation (APD / H) process, the furfural compounds and aldehydes Condensation hydrogenation process, the monofunctional compounds and catalytic upgrading process. The technological conditions, catalyst compositions and chemical reactions of these catalytic processes are summarized. Taking into account the preparation of monosaccharides C6 above hydrocarbons can be directly or mixed into a traditional liquid fuel, this article focuses on the two process routes were summarized in the process of reaction and deoxidation mechanism, and discussed the process of industrialization Need to pay attention to the scientific problems.