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。     

燃油植物橡胶树籽的开发利用

橡胶籽是橡胶树种植产业中的一项副产品资源,估计我国每年可产橡胶籽油15万～18万t.论述了橡胶籽油用于生物柴油的可行性,如能因地制宜开发生物柴油,既可解决植胶农场柴油不足,也可充分利用资源,其生态效益、经济效益均很明显,值得引起有关方面的注意.     

三种植物油及其生物柴油中脂肪酸组成的比较研究

生物柴油油料植物的选择是多样化的。通过对麻疯树,青刺果及乌桕三种产于西南的油料植物油分的理化性质及它们的生物柴油进行GC/MS分析,以麻疯树油为参照油分,对比青刺果油和乌桕油,找出适合作生物柴油油料植物油分的特点,为生物柴油油料植物的选择提供了依据。     

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]     

乌桕油脂成分作为生物柴油原料的研究进展

生物柴油本质上是长链脂肪酸甲酯,工业上多通过酯交换反应进行生产.乌桕是广泛分布于中国的油料树种,其种子油脂含量高达40%左右,是生物柴油的优质原料.本文在介绍能源植物的种类及生物柴油生产概况的同时综述了乌桕皮油和梓油的提取工艺、用于催化乌桕油生产生物柴油的催化剂以及乌桕油及种子中脂肪酸组成等方面的研究进展.规范乌桕种质资源的标准化与分子标记辅助遗传育种、油脂代谢途径机理的揭示及转基因技术创制高含油新品种、新型纳米催化剂及新型高效固定化抗逆脂肪酶的研制对推动乌桕生物柴油的发展具有重要作用.     

在青藏高原地区推广油菜种植并发展生物柴油产业的思考

青藏高原地区是国内最为优良的油菜种植地之一,油菜籽亩产、含油率、千粒质量多次创下全国乃至世界最高纪录。然而目前青藏高原地区油菜产品多以油菜籽形式外销,产品附加值低,并且种植分散、生产成本高,严重限制了青藏高原地区油菜产业的发展。因地制宜地利用丰富的油菜资源发展生物柴油产业,通过生物柴油产业带动油菜产业发展,对于带动农牧民脱贫致富、保护高原生态环境、保障青藏地区燃油供应安全具有重要意义。本文探讨了在青藏高原地区发展生物柴油产业的意义、原料油供应基础及潜力,并对比分析了以菜籽油为原料油制备生物柴油的不同工艺技术。分析表明,在大规模产业化生产下,能够围绕生物柴油产业形成完整的油菜产业链,并在成本进一步降低后产生可观的潜在经济效益。     

生物柴油植物黑皂树开发利用研究

能源短缺和环境污染是当前人类社会所面临的巨大挑战,生物柴油的推广和应用是现阶段解决替代燃油的重要途径之一。黑皂树种子油是很好的生物柴油原料,目前在许多热带地区大力种植黑皂树。我国华南、西南地区的一些干旱荒地可以种植黑皂树。我们对黑皂树油在柴油机上的应用研究证明:黑皂树油在气温35℃条件下,可以直接在各种柴油机上起动和应用;黑皂树油中掺入20%的轻柴油,其黏度大大降低,冷机起动性能和热效率等均与轻柴油相当。因此,黑皂树油的应用比目前国外使用的生物柴油更经济,是一种很有发展前途的能源植物。     

海南省非粮生物柴油能源植物的调查、化学组分的测定及筛选研究

为研究海南省现有非粮生物柴油能源植物的资源特点、资源量和分布情况,对海南省现有资源进行了调查。采集样品的含油部位采用索氏提取法测定其含油量,并用碱催化法进行脂肪酸甲酯化。运用相关计算公式和＂DPS数据处理系统＂对各组分进行数据计算与分析,在第一年度数据基础上,按照生物柴油能源植物初步评价标准,筛选出非粮生物柴油能源植物共计30科、47属、59种（含2变种）,其中,罗志藤（Stixis suaveolens）和海南崖豆藤（Millettia pachyloba）是按此评价标准筛选新增加的种。分析了海南省非粮生物柴油能源植物的资源及其分布特点,对其发展潜力、保护和利用提出了建议。     

麻风果油为原料的生物柴油生产全过程能值分析

生物柴油作为石油的替代能源之一,已在我国开始了产业化应用。采用能值分析方法对以麻风果油为原料的生物柴油生产全过程,包括麻风树的种植、麻风果实的运输、麻风果油的榨取、果油酯化4个过程以及废水的处理进行了评价,从可更新资源、不可更新资源和购买资源入手构建了能值评价指标体系,并与大豆油为原料的生物柴油、小麦为原料的生物乙醇进行了比较。结果表明麻风果油生物柴油的能值转换率是1.67×1013sej/kg,能值产出率是1.85,环境负载率是6.84,可持续发展指数是0.271。比较得出,麻风果油能值转换率是大豆油的3倍,是生物乙醇的2倍;相同经济能值的投入,麻风果油能值产出率最高,但对环境的依赖程度也更强;可持续发展指数三者相差不大。原料的非食用性方面,与大豆生物柴油、生物乙醇相比,麻风果油有很大的优势,具有发展潜力。     

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。     

高含游离脂肪酸的香果树籽油制备生物柴油的方法

目前生物柴油因其环保和可再生利用资源的特性备受关注。多数生物柴油是通过甲醇和碱催化食用油得到的,而大量非食用油也可以制备生物柴油。本文报道用高含游离酸脂肪油快速高效低成本制备成其单酯的二步法工艺。先用1% H2SO4以少于1.5%量对甲醇和云南特产香果树（Lindera communis）籽的粗原料油以10∶1摩尔比组成的混合液酸催化酯化游离脂肪酸;之后再对醇和得到的油脂产品按摩尔比15∶1的混合液碱催化转化为单甲酯和甘油。本方法是一个直接甲脂化制备生物柴油的工艺简洁、降低成本的新技术。文中还讨论了该工艺影响转化效率的主要因素,如摩尔比,催化量,温度,反应时间和酸度。香果树生物柴油不重蒸,而其生物柴油的主要特性,如粘度、热值、比重、闪点、冷滤点等与生物柴油标准的匹配度,也做了报道,研究结果将为香果树生物柴油以非重蒸油料制备生物柴油产品,作为潜在的柴油燃料替代产品提供技术支撑。     

山橿生物特性的初步研究

目的：研究山檀的生长发育规律,为山檀资源的开发利用提供科学依据。方法：以实地调查的方式观测山檀植物生长发育情况;以高效液相色谱法（HPLC）测定山檀根种主要化学成分的动态积累变化规律。结果：描述了山檀的生物特性,了解了山檀的生长发育情况及主要化学成分的动态积累变化规律。结论：研究内容可为山檀野生资源保护开发利用,以及进行规范化种植提供科学依据。     

湘西北腊梅群落优势树种的生理生态学特性研究

对湘西北腊梅群落中 4个优势树种的光合、呼吸、蒸腾以及矿质营养等基本生理生态学指标进行了测试分析。结果表明 ,腊梅和香叶树的光—光合特性较为优良 ,它们对光合有效辐射的适应幅度更宽 ,净光合速率较高。香叶树的暗呼吸强度最低而水分利用效率最高 ,腊梅则对土壤矿质营养的选择性主动吸收能力最强。利川润楠和八角枫的生理生态学特性较之于腊梅和香叶树 ,显示出一定的劣势。     

Biodiesel production from seed oil of Cleome viscosa L

Edible oil seed crops, such as rapeseed, sunflower, soyabean and safflower and non-edible seed oil plantation crops Jatropha and Pongamia have proved to be internationally viable commercial sources of vegetable oils for biodiesel production. Considering the paucity of edible oils and unsustainability of arable land under perennial plantation of Jatropha and Pongamia in countries such as India, the prospects of seed oil producing Cleome viscosa, an annual wild short duration plant species of the Indogangetic plains, were evaluated for it to serve as a resource for biodiesel. The seeds of C. viscosa resourced from its natural populations growing in Rajasthan, Haryana and Delhi areas of Aravali range were solvent extracted to obtain the seed oil. The oil was observed to be similar in fatty acid composition to the non-edible oils of rubber, Jatropha and Pongamia plantation crops and soybean, sunflower, safflower, linseed and rapeseed edible oil plants in richness of unsaturated fatty acids. The Cleome oil shared the properties of viscosity, density, saponification and calorific values with the Jatropha and Pongamia oils, except that it was comparatively acidic. The C. viscosa biodiesel had the properties of standard biodiesel specified by ASTM and Indian Standard Bureau, except that it had low oxidation stability. It proved to be similar to Jatropha biodiesel except in cloud point, pour point, cold filter plugging point and oxidation stability. In view of the annual habit of species and biodiesel quality, it can be concluded that C. viscosa has prospects to be developed into a short-duration biodiesel crop.     

Water demand and stress from oil palm-based biodiesel production in Thailand

Purpose

The use and production of biofuels have been strongly promoted in Thailand. In order to achieve a 25 % renewable energy target in 2021, feedstock expansion is needed to satisfy the increased demand for biofuel production putting more pressure on freshwater resources. This is an important implication of biofuel production which has not yet been taken into consideration. Thus, this study intends to address the impact from freshwater use due to the biodiesel target based on life cycle assessment approach as well as to evaluate suitable areas for expansion of oil palm.

Methods

The amount of water for growing oil palm throughout its lifespan is estimated based on theoretical crop water requirement, while water demand for producing biodiesel is referred to from literature. Then, the potential impact on freshwater resources is assessed in terms of water deprivation using the water stress index of Thailand. The Alternative Energy Development Plan for 2012–2021 and areas recommended by the Ministry of Agriculture and Cooperatives are referred in this study. Additionally, two scenarios for increasing new plantation in suitable areas are proposed as expansion in a single region or spread over the three regions.

Results and discussion

The highest water requirement for oil palm-based biodiesel production is found in the central region followed by the eastern and southern (4–9, 5–16, and 4–19 m³ L^?1 biodiesel, respectively). This is because oil palm plantations in the central region are not yet fully mature. As a result, the ratio of crop water requirement associated to crop productivity will be reduced while the water productivity will be increased yearly in yield. Also, more than 99 % of the total water is required during the cultivation period. To achieve the 2021 biodiesel target with a concern towards the impact from freshwater use by means of low water deprivation, cultivating oil palm is recommended entirely in the eastern and the southern parts without expansion to the central region.

Conclusions

The impact on freshwater resources is an important implication of biofuel production as most of the water requirement of palm oil biodiesel was for oil palm cultivation. Accounting the water deprivation as one of the criteria on impact from freshwater use will provide useful support for selecting areas having less potential for inducing water stress in a watershed leads to people in these areas being less vulnerable to water stress.

     

樟科植物中脂肪酸成分的分布

本文报道了樟科11个属49种种子油和‘种果肉油的脂肪酸成分。其中樟族和木姜子族的各属种(滇新樟除外)种子油脂肪酸成分以 C_(10)、C_(12)和 C_(14)饱和或烯酸为主。而厚壳桂属、润楠和楠属种子油脂肪酸成分主要为棕榈酸、油酸和亚油酸。山苍子、天目木姜子、大果山胡椒、山橙、红脉钓樟、鸭公树和锈叶新木姜子种子油中的 C_(10)、C_(12)和 C_(14)烯酸经分离鉴定均是顺式Δ~4烯酸。     

Studies of Terminalia catappa L. oil: characterization and biodiesel production

Since the biodiesel program has been started in Brazil, the investigation of alternative sources of triacylglycerides from species adapted at semi-arid lands became a very important task for Brazilian researchers. Thus we initiated studies with the fruits of the Terminalia catappa L (TC), popularly known in Brazil as "castanhola", evaluating selected properties and chemical composition of the oil, as well any potential application in biodiesel production. The oil was obtained from the kernels of the fruit, with yields around 49% (% mass). Also, its fatty acid composition was quite similar to that of conventional oils. The crude oil of the TC was transesterified, using a conventional catalyst and methanol to form biodiesel. The studied physicochemical properties of the TC biodiesel are in acceptable range for use as biodiesel in diesel engines.     

Continuous-flow biodiesel production using slit-channel reactors

Slit-channel reactors are reactors whose active surface areas are orders of magnitude higher than those of micro-reactors but have low fabrication costs relative to micro-reactors. We successfully produced biodiesel with different degrees of conversion using homogeneous catalyst in the slit-channel reactor. The reactor performance shows that percent conversion of soybean oil to biodiesel increases with channel depth, as expected, due to more efficient mixing. Shallow slit-channels require short average residence times for complete product conversion. Present results show that the slit-channel reactor provides an improved performance over traditional batch reactors using homogeneous sodium alkoxide catalyst. It is aimed to couple the reactors with solid catalysts in converting soybean oil to biodiesel and implementation method is suggested. The cost advantages resulting from the ease of fabrication of slit-channel reactors over micro-reactors and how these factors relate to the oil conversion efficiency to biodiesel are briefly noted and discussed.     

Desert date (Balanites aegyptiaca) as an arid lands sustainable bioresource for biodiesel

The aim of this study was to assess the suitability of Desert date (Balanites aegyptiaca L. Delile) as an oil crop in arid lands for large-scale sustainable industrial biodiesel production. Characterization of the Desert date plant material showed that using proper cultivation practices with emphasis on low quality irrigation water trees can be extremely well developed in hyper-arid conditions of the Israeli Arava desert and yield oil-rich fruits. Best selected trees can yield date fruits up to 52 kg/trees. Desert date kernels oil content may reach up to 46.7% (based on dry weight). The oil is consisted on four major fatty acids: palmitic (16:0), stearic (18:0), oleic (18:1), and linoleic (18:2), constituting 98-100% of the total fatty acids in the oil of all tested genotypes. Linoleic acid was the most prevalent fatty acid, ranging from 31% to 51% of the fatty acids profile, very similar to soybean oil profile. In situ biodiesel production directly from oil-enriched powder was successfully developed. Yield efficiency for both conventional and in situ biodiesel production was about 90%. The qualities of the produced biodiesel well meet the international biodiesel standards. The present study clearly demonstrated Desert date as a model for the utilization of bioresources in the Israeli Arava desert and potentially other similar areas for cost-effective biodiesel production.     

Biodiesel production from Jatropha oil by catalytic and non-catalytic approaches: an overview

Biodiesel (fatty acids alkyl esters) is a promising alternative fuel to replace petroleum-based diesel that is obtained from renewable sources such as vegetable oil, animal fat and waste cooking oil. Vegetable oils are more suitable source for biodiesel production compared to animal fats and waste cooking since they are renewable in nature. However, there is a concern that biodiesel production from vegetable oil would disturb the food market. Oil from Jatropha curcas is an acceptable choice for biodiesel production because it is non-edible and can be easily grown in a harsh environment. Moreover, alkyl esters of jatropha oil meet the standard of biodiesel in many countries. Thus, the present paper provides a review on the transesterification methods for biodiesel production using jatropha oil as feedstock.