地沟油超临界酯交换法制备生物柴油

地沟油制备生物柴油作为可再生能源具有巨大的潜力。作为制备生物柴油的原料,地沟油具有可再生、环境友好、使用和运输安全等优点。地沟油需经过酯交换转化为生物柴油。文中介绍了酯交换法在地沟油制备生物柴油生产中的应用,其中着重介绍地沟油经超临界甲醇酯交换法制备生物柴油。提出地沟油超临界酯交换制备生物柴油研究意见及优化工艺方法。     

植物油作为发动机燃料及生物柴油制备的研究

本文详细介绍了植物油作为发动机燃料的4种应用方式。生物柴油是绿色可再生能源，由动植物油的酯交换反应获得。讨论了生物柴油制备过程中的反应动力学以及水份、游离脂肪酸、催化剂、醇油摩尔比、反应温度等对酯交换的影响。     

生物柴油制备新进展

介绍了国内外酯交换制备生物柴油的最新进展.目前酯交换法制备生物柴油主要有4种方法：均相酸碱催化法、酶催化法、超临界法和非均相催化剂催化法,综合比较了4种酯交换生产方法的优缺点,同时介绍了生物柴油制备的最新进展,指出了生物柴油的发展趋势.     

水力空化强化高芥酸菜籽油联产生物柴油和芥酸甲酯

水力空化条件下,以高芥酸菜籽油为原料,研究了醇-油不相溶体系的酯交换反应.结果表明:水力空化技术能大大缩短酯交换反应达到平衡的时间;与机械搅拌反应体系相比,在反应温度60℃、醇油摩尔比6∶1、催化剂用量1.0％ KOH的条件下,反应平衡时间可从60min缩短至30min,油酯的转化率从94％提高到99％,水力空化技术可强化醇油互不相溶体系酯交换反应传质过程,是一种高效的生物柴油制备方法.同时通过实验以高芥酸菜籽油为原料制备出高品质的生物柴油和高附价值的芥酸甲酯,为我国发展菜籽油生物柴油降低生产成本提供新思路.     

制备生物柴油所用催化剂的研究进展

生物柴油作为一种清洁的可再生能源,可以由动植物油脂通过酯交换反应来制备.本文概述了近年来制备生物柴油的多种催化剂,并探讨了各自的优点及缺陷.     

生物柴油制备以及在柴油机上应用的关键技术研究

针对工业上生产生物柴油的制备技术、工艺流程、酯交换反应影响因素、质量指标以及在柴油机上燃烧的关键技术等进行了综述。国内外仍然以酯交换法反应为主,且常以氢氧化钠等碱为催化剂。如何降低生物柴油中甲醇、甘油、水含量以及研制适用于生物柴油的抗氧化剂均是生物柴油应用的关键技术。关于多种生物柴油的掺混燃烧以及燃用生物柴油导致的排放对于生物系统的细胞毒害性和突变性等涉及人类健康影响的研究仍然有待加强。     

甲醇/乙醇均相体系酯交换制备生物柴油的研究

为解决酯交换反应中甲醇与植物油呈两相不互溶的问题,研究了在甲醇/乙醇均相体系中,植物油在NaOH催化剂条件下通过酯交换反应制备生物柴油的工艺.结果表明,添加乙醇能有效提高反应速率.通过Box-Benhnken试验,得到最佳工艺条件:反应温度为48.2℃、催化剂用量为植物油质量的0.59%、反应时间为25.4 min.在此工艺条件下,生物柴油转酯化率为99.3%,产品的主要性能指标符合我国生物柴油标准(GB/T20828-2007).     

高酸值油料一步法制备生物柴油研究

以酸值123.04 mg KOH/g的棕榈油脱臭馏出物(PFAD)为原料,在带压反应器中,用浓硫酸为催化剂,采用一步法催化酯化反应制备生物柴油。重点研究反应温度、反应时间、催化剂用量和醇油比等因素对酯化和酯交换反应的影响。结果表明,提高反应温度能促进酯化反应和酯交换反应,使高酸值原料经一次反应直接转化为目的产物——脂肪酸甲酯,从而缩短制备流程,降低成本,强化酯化反应进行,提高脂肪酸甲酯收率。当催化剂用量为0.5%(质量分数)、醇油物质的量之比7∶1、在130℃反应90 min后,生物柴油的最高收率达到88.1%。较之酸碱两步法催化高酸值油料制备生物柴油能显著缩短反应时间、简化工艺流程、降低生产成本。     

微藻直接离子液体脂肪酶制备生物柴油

采用小球藻、甲醇为原料,脂肪酶为催化剂,离子液体为提取剂和反应介质,直接提取酯交换制备生物柴油。考察不同工艺条件对产率的影响,结果表明:甲醇用量和藻粉质量比为8∶1,离子液体[BMIM][DCA]和藻粉质量比为1∶1,脂肪酶用量为藻粉质量的12%,反应温度为50℃,酯交换反应时间为16 h条件下,生物柴油的转化率可达69.6%。采用微藻直接离子液体脂肪酶制备生物柴油无需从微藻粉中提取油脂,因此降低过程成本、缩短工艺,能实现含油微藻到生物柴油的一步转化。     

棉籽酸化油酸催化两步法制备生物柴油的研究

以棉籽酸化油和甲醇为原料,采用酸催化两步法制备生物柴油.第一步为酸催化酯化和一次酯交换反应,第二步为酸催化二次酯交换反应.通过大量试验优化了反应条件:在酯化和一次酯交换阶段,醇油质量比为0.5:1,催化剂用量为棉籽酸化油质量的3%,反应温度为90℃,反应时间为150 min:在二次酯交换阶段,醇油质量比为0.7:1,催化剂用量为棉籽油质量的4%,反应时间为90min.在此条件下,生物柴油的产率达到94%以上,产品质量符合国家标准.     

Optimization of biodiesel production from Pungamia oil by Taguchi’s technique

In biodiesel production process, not all fatty acid chains are turned into alkyl esters (biodiesel). This phenomenon reduces the biodiesel quality and yield significantly. Therefore, optimization of biodiesel production process is very much essential to attain maximum yield. In this work, biodiesel production from raw Pungamia oil was optimized by using Taguchi’s method. The L9 orthogonal array was used to optimize the maximum yield of biodiesel production. The parameters like stirrer speed, concentration of NaOH catalyst, and reaction time for producing maximum yield of methyl esters from raw Pungamia oil is reported. In this analysis, signal-to-noise ratio (S/N ratio) and the analysis of variance (ANOVA) are employed to identify and quantify the maximum yield. The analysis revealed that 550 rpm stirrer speed, 15 g of NaOH catalyst, and 80 min reaction time are the optimum parameters for methyl esters of biodiesel production from raw Pungamia oil.     

Biodiesel production by transesterification of duck tallow with methanol on alkali catalysts

Duck tallow was employed as a feedstock for the production of biodiesel by transesterification with methanol. The content of fatty acid methyl ester (FAME) was evaluated on various alkali catalysts during transesterification. The composition and chemical properties of the FAME were investigated in the raw duck tallow and the biodiesel products. The major constituent in the biodiesel product was oleic acid. The FAME content was 97% on KOH catalyst in the reaction. It was acceptable for the limit of European biodiesel qualities for BD100. Acid value, density, and kinematic viscosity of the biodiesel products also came up to the biodiesel qualities.     

我国生物质能源现代化应用前景展望(二)——生物质制备液体燃料的转化途径

利用可再生生物质资源转化制备液体燃料已成为全球关注的热点。常见的生物质能源原料主要有草本植物、木本植物、微藻和脂肪类生物质资源,丰富的生物质资源为生物质液体燃料的生产提供了广泛的原料来源,也为生物质能源的多样性发展提供了坚实的物质基础。不同的生物质原料种类和转化方式可生产出性能各异的多种液体燃料,主要包括醇类燃料(乙醇、丁醇等)、烃类燃料和生物柴油等,由此构建出生物质转化制备液体燃料的转化途径网络。醇类燃料的生物质转化途径主要包括生物质直接发酵、生物质合成气发酵、生物质合成气化学合成等;烃类燃料的生物质转化途径主要有生物质液化加氢、微藻热化学途径、生物质合成气费托合成、生物质发酵脂肪酸加氢及油脂类加氢途径等;生物柴油的转化途径主要有油脂酯交换和微藻萃取酯交换。在这些液体燃料的转化途径中,只有生物质发酵制乙醇途径和油脂酯交换途径基本实现了商业化应用,其他大部分转化途径仍处于开发阶段。     

Quality analysis studies on biodiesel production of neochloris oleoabundans algae

The petroleum fuels play a major role in industry, agriculture, and transport besides meeting out many other basic human needs. However, fossil fuels are limited in quantity and are depleting day by day as the consumption is increasing very rapidly. Biodiesel is one such fuel in which there is a lot of hope. In the recent past, biodiesel received considerable attention as a renewable fuel. In India, it has not been possible to produce biodiesel from edible oils since the same is very scarce. Hence, the scope of opting to non-edible oils from plants as raw material for biodiesel production recently gained momentum. This paper presents the production of biodiesel from nonedible, Neochloris oleoabundans oil and its characterization. The studies were carried out on transesterification of oil with methanol, sodium hydroxide, and Sodium methoxide as catalyst for the production of biodiesel. The process parameters such as catalyst concentration, reaction time, and reaction temperature were optimized for the production of Neochloris oleoabundans oil biodiesel. The biodiesel yield of 95.15% was noticed at optimal process parameters.     

A review on biodiesel production using catalyzed transesterification

Biodiesel is a low-emissions diesel substitute fuel made from renewable resources and waste lipid. The most common way to produce biodiesel is through transesterification, especially alkali-catalyzed transesterification. When the raw materials (oils or fats) have a high percentage of free fatty acids or water, the alkali catalyst will react with the free fatty acids to form soaps. The water can hydrolyze the triglycerides into diglycerides and form more free fatty acids. Both of the above reactions are undesirable and reduce the yield of the biodiesel product. In this situation, the acidic materials should be pre-treated to inhibit the saponification reaction. This paper reviews the different approaches of reducing free fatty acids in the raw oil and refinement of crude biodiesel that are adopted in the industry. The main factors affecting the yield of biodiesel, i.e. alcohol quantity, reaction time, reaction temperature and catalyst concentration, are discussed. This paper also described other new processes of biodiesel production. For instance, the Biox co-solvent process converts triglycerides to esters through the selection of inert co-solvents that generates a one-phase oil-rich system. The non-catalytic supercritical methanol process is advantageous in terms of shorter reaction time and lesser purification steps but requires high temperature and pressure. For the in situ biodiesel process, the oilseeds are treated directly with methanol in which the catalyst has been preciously dissolved at ambient temperatures and pressure to perform the transesterification of oils in the oilseeds. This process, however, cannot handle waste cooking oils and animal fats.     

Macroalgae: Raw material for biodiesel production

The objective of this paper is to study marine macroalgae as an alternative raw material for the biodiesel production. The obtained results show that biodiesel production from oil extracted from marine algae is feasible by transesterification. Oil extraction can be carried out simultaneously with the transesterification. To investigate the optimum reaction conditions, the reaction was carried out at various methanol to oil molar ratios, catalyst concentrations and reaction temperatures. The process yields 1.6–11.5% depending on the reaction conditions. Moreover, the properties of macroalgae transesterification residue after transesterification were analyzed, concluding that it is a suitable material for fuel pellets manufacturing.     

Microalgal biodiesel in China: Opportunities and challenges

With rapid economic development, energy consumption in China has tripled in the past 20 years, exceeding 2.8 billion tons of standard coal in 2008. The search for new green energy as substitutes for nonrenewable energy resources has become an urgent task. Biodiesel is one of the most important bioenergy sources. According to the Mid- and Long-term Development Plan for Renewable Energy in China, the consumption of biodiesel in China will reach 0.2 million tons in 2010 and 2.0 million tons in 2020. However, large-scale production of biodiesel is restricted by the limited sources of raw materials. Microalgal oil is a prospective raw material for biodiesel production. Development of technology for the production and commercialization of biodiesel from microalgae has become a hot topic in the field of bioenergy and CO₂ emission mitigation. Biodiesel from microalgae can be produced at laboratory-scale, but the cost is too high. Few studies on the commercialization of the technology of producing biodiesel from microalgae have been reported. In this review, recent progress on the research and development of biodiesel from microalgae that have resulted in scientific breakthroughs and innovation in engineering in China are introduced. The existing challenges are also discussed. Based on a detailed analysis, several novel strategies on commercial biodiesel production from microalgae are proposed.     

Waste capiz (Amusium cristatum) shell as a new heterogeneous catalyst for biodiesel production

The waste Capiz shell was utilized as raw material for catalyst production for biodiesel preparation. During calcination process, the calcium carbonate content in the waste capiz shell was converted to CaO. This calcium oxide was used as catalyst for transesterification reaction between palm oil and methanol to produce biodiesel. The biodiesel preparation was conducted under the following conditions: the mole ration between methanol and palm oil was 8:1, stirring speed was 700 rpm, and reaction temperature was 60 °C for 4, 5, and 6 h reaction time. The amount of catalyst was varied at 1, 2, 3, 4, and 5 wt %. The maximum yield of biodiesel was 93 ± 2.2%, obtained at 6 h of reaction time and 3 wt % of amount of catalyst. In order to examine the reusability of catalyst developed from waste of capiz (Amusium cristatum) shell, three transesterification reaction cycles were also performed.     

Biodiesel production from waste chicken fat based sources and evaluation with Mg based additive in a diesel engine

In this study, chicken fat biodiesel with synthetic Mg additive was studied in a single-cylinder, direct injection (DI) diesel engine and its effects on engine performance and exhaust emissions were studied. A two-step catalytic process was chosen for the synthesis of the biodiesel. Methanol, sulphuric acid and sodium hydroxide catalyst were used in the reaction. To determine their effects on viscosity and flash point of the biodiesel, reaction temperature, methanol ratio, type and amount of catalyst were varied as independent parameters. Organic based synthetic magnesium additive was doped into the biodiesel blend by 12 μmol Mg. Engine tests were run with diesel fuel (EN 590) and a blend of 10% chicken fat biodiesel and diesel fuel (B10) at full load operating conditions and different engine speeds from 1800 to 3000 rpm. The results showed that, the engine torque was not changed significantly with the addition of 10% chicken fat biodiesel, while the specific fuel consumption increased by 5.2% due to the lower heating value of biodiesel. In-cylinder peak pressure slightly rose and the start of combustion was earlier. CO and smoke emissions decreased by 13% and 9% respectively, but NO_x emission increased by 5%.     

Biofuel and biomass from marine macroalgae waste

Nowadays, biofuel production of new raw materials has gained renewed interest. For that reason, the objective of this work is to use marine macroalgae for biodiesel and biomass production. The obtained results show that macroalgae are a suitable energy source for biodiesel production by direct transesterification, avoiding the previous step of oil extraction. It is an effective process because 95% of the oil is extracted. To analyze the optimum reaction conditions, the reaction was carried out at different amounts of methanol, catalyst concentrations, reaction temperatures, and reaction times. In addition, the macroalgae residue after transesterification was analyzed and it is suitable as fuel in biomass boilers.