一种绿色燃料——生物柴油

概要介绍了生物柴油的原料资源、特性、生产方法和国内外生物柴油发展概况,并分析了我国发展生物柴油的战略意义,旨在为生物教学提供参考资料。     

生物柴油研究进展

介绍了国内外生物柴油的发展现状,探讨了我国发展生物柴油的原料来源途径,包括木本油料植物、转基因油料作物、废弃油脂、微生物油脂和微藻油脂等,综述了制备生物柴油的化学法、酶法、超临界法等生产技术及其进展,概括了当前生物柴油主要的品质问题与改性对策,分析了生物柴油副产物的高值化利用策略,指出了我国生物柴油产业化面临的原料、技术和生物炼制方面的主要问题。     

生物柴油的应用研究进展

综述了国内外生物柴油的应用和生产现状,介绍了生物柴油的主要特性以及直接混合、微乳液、高温热裂解、化学酯交换、生物酶催化和超临界甲醇法等生产生物柴油的方法,阐述了我国发展生物柴油的重要意义,并提出了我国发展生物柴油技术的建议。     

我国微藻生物柴油的研究背景与发展战略

生物柴油是可再生能源开发利用的重要发展方向。藻类制备生物柴油具有产油量高、生长速度快、环境适应能力强、不与农作物争夺农田和淡水资源等优势。从微藻制备生物柴油着手,简要介绍了生物柴油的生产原料与发展历程、微藻油脂的组成与生物合成途径、微藻制备柴油的工艺与瓶颈及解决策略,最后对微藻制备生物柴油技术提出了近中远期发展目标及展望。     

我国生物柴油产业化现状及前景

生物柴油是石化柴油的一种优良替代品，发展生物柴油有助于缓解能源危机，减少污染物的排放。本文从原料、技术、现有生产能力等方面概述了生物柴油在我国的产业化发展现状，并针对我国生物柴油产业发展提出了建议。[编者按]     

我国生物柴油产业的回顾与展望

本文回顾了近年来我国生物柴油产业的发展历程,分析了我国生物柴油生产原料的主要来源,并就生物柴油的生产技术及相应的国内代表性企业进行了综述,最后对我国生物柴油的未来发展方向进行了展望。     

发展生物柴油产业的挑战与对策的探讨

生物柴油是一种由可再生资源生产的优质清洁燃料,发展生物柴油不仅可以保护环境,减少温室气体排放,而且可以缓解我国石油进口的压力,推动新农村建设。但由于植物油脂价格的飙升,生物柴油产业发展面临仅生产生物柴油燃料在经济上难以立足的挑战。本文从发展生物柴油原料资源,生产技术以及生物柴油化工技术开发的现状与未来发展动态进行分析,探讨了促进我国生物柴油产业健康发展的对策。[编者按]     

微藻生物柴油的发展

微藻生物柴油是一种具有较大发展潜力的可再生能源,与动、植物为原料制备的生物柴油相比,它有不占用耕地、产油效率高等优点。目前,微藻生物柴油在国内外都有很大发展,产业化的进程也在逐步推进。介绍了高油脂含量微藻的种类、微藻合成油脂的机理研究、微藻的培养技术及微藻生物柴油的产业化现状,并对微藻生物柴油发展中的一些问题进行了分析。     

生物柴油产业发展和相关政策分析

<正>生物柴油作为一种可再生的新型液体燃料备受关注,越来越多的国家和地区通过政策扶持和资金支持发展生物柴油产业。介绍了生物柴油产业化发展和技术发展趋势,并着重对各主要生物柴油生产国家和地区的政策进行了分析。     

中国生物柴油产业发展的瓶颈何在

生物柴油是优质的石油柴油代用品,但是,在我国的生物柴油发展却在快速发展的初期过后,陷入了举步维艰的境地,究竟是什么让中国的生物柴油裹足不前？我们能从国外发展种获得何种启迪呢？     

Biodiesel production with immobilized lipase: A review

Fatty acid alkyl esters, also called biodiesel, are environmentally friendly and show great potential as an alternative liquid fuel. Biodiesel is produced by transesterification of oils or fats with chemical catalysts or lipase. Immobilized lipase as the biocatalyst draws high attention because that process is “greener”. This article reviews the current status of biodiesel production with immobilized lipase, including various lipases, immobilization methods, various feedstocks, lipase inactivation caused by short chain alcohols and large scale industrialization. Adsorption is still the most widely employed method for lipase immobilization. There are two kinds of lipase used most frequently especially for large scale industrialization. One is Candida antartica lipase immobilized on acrylic resin, and the other is Candida sp. 99–125 lipase immobilized on inexpensive textile membranes. However, to further reduce the cost of biodiesel production, new immobilization techniques with higher activity and stability still need to be explored.     

酶法合成生物柴油工业化研究进展

介绍了北京化工大学近年来酶法合成生物柴油工业化研究的结果。主要内容包括以下几个方面:高产脂肪酶菌株的选育、脂肪酶发酵工艺优化及放大、脂肪酶固定化方法、酶反应器放大、生物柴油分离精制及副产物甘油综合利用。该脂肪酶假丝酵母Candida sp.99-125在5 m3罐发酵活力不低于8 000 IU/mL,然后将该脂肪酶吸附固定在织物膜上并进行表面改性,用于搅拌罐式反应器生产每吨甲酯的需酶量仅为4.2 kg,产品经分离精制调质后,其各项指标完全符合德国生物柴油生产标准。副产物甘油可用于1,3-丙二醇发酵,30 L发酵罐中1,3-丙二醇的产量可达到76.1 g/L。     

Lipase catalyzed transesterification of soybean oil using ethyl acetate,an alternative acyl acceptor

Methanol, the acyl acceptor usually used in the commercial process of biodiesel production, is associated with some problems such as immiscibility with oils and lipase deactivation. To overcome these barriers, ethyl acetate was proposed as an alternative acyl acceptor for the production of biodiesel from soybean oil using an immobilized lipase, Novozym 435, Ethyl acetate mixed well with soybean oil, and only slightly inhibited the lipase activity by 5%. The effects of various environmental parameters, such as the composition of soybean oil and ethyl acetate, lipase content, and reaction temperature, were investigated to determine the optimal conditions for biodiesel production. As a result, the highest biodiesel production yield, 63.3 (±0.6)%, was obtained by using an ethyl acetate and soybean oil mixture with a 6∶1 molar ratio, with 8% of the immobilized lipase based on the weight of oil added at 70°C and 600 rpm.     

Production of biodiesel by Burkholderia cepacia lipase as a function of process parameters

Despite the already established route of chemically catalyzed transesterification reaction in biodiesel production, due to some of its shortcomings, biocatalysts such as lipases present a vital alternative. Namely, it was noticed that one of the key shortcomings for the optimization of the enzyme catalyzed biodiesel synthesis process is the information on the lipase activity in the reaction mixture. In addition to making optimization difficult, it also makes it impossible to compare the results of the independent research. This article shows how lipase intended for use in biodiesel synthesis can be easily and accurately characterized and what is the enzyme concentration that enables achievement of the desired level of fatty acid methyl esters (FAME) in the final product mixture. Therefore, this study investigated the effect of two different activity loads of Burkholderia cepacia lipase on the biodiesel synthesis varying the pH and temperature optimal for lipase activity. The optimal lipase pH and temperature were determined by two different enzyme assays: spectrophotometric and titrimetric. The B. cepacia lipase pH optimum differentiated between assays, while the lipase optimally hydrolyzed substrates at 50°C. The analysis of FAME during 24 hr of biodiesel synthesis, at two different enzyme concentrations, pH 7, 8, and 10, and using two different buffers, revealed that the transesterification reaction at optimal pH, 1 hr reaction time and lipase activity load of 250 U per gram of reaction mixture was sufficient to produce more than 99% FAME.     

Selection of lipase producing yeasts for methanol-tolerant biocatalyst as whole cell application for palm-oil transesterification

Methanol-tolerant lipase producing yeast was successfully isolated and selected thorough ecological screening using palm oil-rhodamine B agar as one step-approach. All 49 lipase-producing yeasts exhibited the ability to catalyze esterification reaction of oleic acid and methanol at 3 molar equivalents. However, only 16 isolates catalyzed transesterification reaction of refined palm oil and methanol. Rhodotorula mucilagenosa P11I89 isolated from oil contaminated soil showed the strongest hydrolytic lipase activity of 1.2U/ml against palm oil. The production of oleic methyl ester and fatty acid methyl ester (FAME) of 64.123 and 51.260% was obtained from esterification and transesterification reaction catalyzed by whole cell of R. mucilagenosa P11I89 in the presence of methanol at 3 molar equivalents against the substrates, respectively. FAME content increased dramatically to 83.29% when 6 molar equivalents of methanol were added. Application of the methanol-tolerant-lipase producing yeast as a whole cell biocatalyst was effectively resolved major technical obstacles in term of enzyme stability and high cost of lipase, leading to the feasibility of green biodiesel industrialization.     

Biocatalysis: Towards ever greener biodiesel production

The cost of lipases and the relatively slower reaction rate remain as the major obstacles for enzymatic production of biodiesel as opposed to the conventional chemical processes. This paper reviews the starting oils usually employed in biodiesel production, the processes for transforming them to biodiesel placing particular emphasis on enzymatic transesterification. The pros and cons of the lipase-based process, the key operational variables and the technological alternatives for attenuating lipase deactivation are also discussed. Finally, suggestions are made for future studies, paying particular attention to the use of whole cell immobilization in the production process, as this methodology may reduce both the cost of the biocatalyst and dependence on lipase manufacturers.     

我国优势油脂类生物柴油植物蓖麻的种质资源发掘和生物柴油利用

发展可再生生物质能源是解决人类能源危机和环境污染的重要途径。利用边际土地发展油脂类生物质能是生物质能的重要组成部分。蓖麻因为适应性强和油脂成份独特被誉为"理想的生物柴油植物"。蓖麻是我国优势油脂类能源植物,利用边际土地,发展蓖麻产业为我国生物柴油产业化提供原料,是我国现阶段生物柴油产业化发展的相对理想而又现实的选择,而且具有重要的发展前景和巨大的发掘潜力。立足我国现阶段生物柴油产业化的瓶颈问题,着重阐述了蓖麻种质资源发掘的现状、优良品种培育的途径和发展前景,以及利用蓖麻种子油生产商业化生物柴油的现状,以期推动我国利用边际土地发展蓖麻产业以及生物柴油商业化生产。     

Biodiesel fuel production via transesterification of oils using lipase biocatalyst

Biodiesel has gained widespread importance in recent years as an alternative, renewable liquid transportation fuel. It is derived from natural triglycerides in the presence of an alcohol and an alkali catalyst via a transesterification reaction. To date, transesterification based on the use of chemical catalysts has been predominant for biodiesel production at the industrial scale due to its high conversion efficiency at reasonable cost. Recently, biocatalytic transesterification has received considerable attention due to its favorable conversion rate and relatively simple downstream processing demands for the recovery of by-products and purification of biodiesel. Biocatalysis of the transesterification reaction using commercially purified lipase represents a major cost constraint. However, more cost-effective techniques based on the immobilization of both extracellular and intracellular lipases on support materials facilitate the reusability of the catalyst. Other variables, including the presence of alcohol, glycerol and the activity of water can profoundly affect lipase activity and stability during the reaction. This review evaluates the current status for lipase biocatalyst-mediated production of biodiesel, and identifies the key parameters affecting lipase activity and stability. Pioneer studies on reactor-based lipase conversion of triglycerides are presented.     

纳米载体固定化脂肪酶及其在生物柴油转化中的应用进展

随着全球能源需求量的不断上升和日益加剧的环境压力,固定化脂肪酶在可持续生物柴油合成中的应用受到广泛关注。纳米材料,包括纳米粒子(磁性和非磁性)、碳纳米管和纳米静电纺丝,具有比表面积大、结构稳定、易于功能化修饰等优势,是固定化脂肪酶领域的重要载体之一。综述了纳米材料作为载体在脂肪酶固定化中的应用,重点介绍这类生物催化剂在生物柴油合成中的最新进展,并对纳米材料固定化脂肪酶发展前景进行展望,旨在为固定化脂肪酶的研究和工业化应用奠定基础。     

Perspectives for biotechnological production of biodiesel and impacts

In recent years, biological ways for biodiesel production have drawn an increasing attention and compared to chemical approaches, lipase-mediated alcoholysis for biodiesel production has many advantages. Currently, there are extensive reports about enzyme-mediated alcoholysis for biodiesel production, and based on the application forms of biocatalyst, the related research can be classified into immobilized lipase, whole cell catalyst, and liquid lipase-mediated alcoholysis for biodiesel production, respectively. This mini-review is focusing on the study of the aforementioned three forms of biocatalyst for biodiesel production, as well as its impacts and prospects.