木质纤维素生产燃料乙醇的关键技术研究现状

Progress in Research of Key Techniques for Ethanol Production from Lignocellulose

木质纤维素是自然界广泛存在且廉价的可再生资源,其主要成分纤维素、半纤维素是潜在的燃料乙醇生产原料.虽然由木质纤维素生产燃料乙醇的技术路线已具可行性,但存在着具体工艺环节复杂、生产能耗高等局限,严重阻碍了其规模化生产.目前纤维素燃料乙醇生产主要围绕预处理、酶解、发酵三大关键步骤进行技术攻关,其中预处理的能耗和效率、发酵过程的五碳糖利用等问题成为该工艺的重要制约因素.本文在综述国内外纤维素乙醇生产关键步骤的基础上,着重分析了各种物理、化学和生物预处理的优缺点以及新兴的预处理思路,归纳了各类纤维素乙醇生产菌的特点,包括耐高温和五碳糖的利用,并介绍了当前主要的发酵方式和优化措施,以期为木质纤维素生产乙醇提供新的研究思路.

Lignocellulose, with cellulose and hemicellulose as its main components, extensively occurs in the world and is a kind of cheap renewable resource for ethanol production. Although the technical route of bioethanol production from lignocellulose is feasible, the industrial application is limited by its practical obstacles. At present, the studies on ethanol production from lignocellulose mainly focus on three critical steps： pretreatment, enzymatic hydrolysis and fermentation. Particularly, the energy cost and the efficiency of the pretreatment, along with the usage of pentose in fermentation become the crucial limitations of this process. Based on reviewing key techniques for bioethanol production from lignocellulose, advantages and disadvantages of various physical, chemical and biological pretreatments, along with the latest methods, were analyzed. Moreover, the characteristics of many kinds of microbes, such as their thermotolerance and ability of pentose＇ s usage, and the widely-used fermentation modes are also summarized in this review to provide some new ideas for ethanol production from lignocellulose. Tab 5, Ref 86