生物柴油制备新工艺的研究进展

综述了生物柴油的特性及其生产方法,介绍了酯交换法制备生物柴油的反应机理及其近年来出现的各种新生产工艺,包括超临界法、生物催化法、超声波法、离子液体法等,指出了生物柴油技术发展面临的问题及研究方向。     

利用超临界技术制备生物柴油的研究现状

分析了超临界技术制备生物柴油的反应机理,重点阐述了温度、醇油比、压力、水、游离酸对超临界法制备生物柴油的影响.研究表明:超临界技术制备生物柴油在反应时间、对原料要求和产物回收等方面均具有传统碱催化法无法比拟的优势.展望了超临界技术制备生物柴油的工业应用前景,并对超临界技术制备生物柴油的研究提出了建议.     

生物柴油及其生产技术的进展

介绍了由可再生油脂原料衍生的环保燃料生物柴油在国内外应用现状,重点介绍了酯交换法制备生物柴油技术研究进展情况,展望了生物柴油产业在我国的发展前景。     

酯交换法制备生物柴油及其在我国的实践

生物柴油是一种对环境友好的可再生燃料,以其是好的环境效应受到越来越多的关注。综述并比较了生物柴油的各种化学制备方法,介绍了该产业的国内外生产应用情况,指出了生物柴油的优势,分析了生物柴油在生产厦使用过程中存在的一些问题并对生物柴油的未来研究与发展作了展望。     

菜籽油超声波法制备生物柴油的研究

以菜籽油和甲醇为反应原料,以KNO3/Al2O3为催化剂,采用超声波法制备生物柴油,考察了超声波频率、醇油物质的量比、催化剂用量等条件对反应的影响。试验结果表明,该反应的最佳条件:超声波频率为30kHz,醇油物质的量比为7∶1,催化剂用量为菜籽油质量的2.0%。在此条件下,生物柴油产率为94%。所得生物柴油的主要性能指标均符合德国的生物柴油标准。     

超声波制取生物柴油工艺技术探讨

介绍了新兴的超声波制取生物柴油工艺技术,并与液体碱催化技术进行了比较。众多试验结果表明,超声波能加速酯交换反应,反应时间仅需5-30min,其催化剂消耗量仅为液体碱催化技术的30％-50％,甲酯转化率可达99％。但在工业化应用方面仍需要原料预处理、甲醇回收、甲酯洗涤以及甲酯干燥等工艺过程。据估算,商业规模生物柴油加工中超生波处理的成本在0．002～0．015欧元／L之间。     

以棉籽油皂脚为原料制备生物柴油

文章探讨了在酸性催化剂作用下以酸化的棉籽油皂脚为原料制备生物柴油的工艺,为棉籽油生产过程中产生的废料--棉籽油皂脚的回收利用开辟了一条新的途径.试验考察了催化剂用量、反应时间、投料比等因素对反应收率的影响,并通过正交试验优化得到了最佳工艺条件:催化剂(浓硫酸)用量4%(以脂肪物质量计),反应时间10 h,脂肪物与甲醇物质的量比为1:10.在上述最优条件下产品收率可达83%.     

大豆油制备生物柴油的工艺探索

试验研究了大豆油在催化剂（NaOH）的作用下与甲醇发生转脂化反应生成脂肪酸甲酯（生物柴油）的工艺条件。试验结果表明，该转脂化反应的最佳操作条件：NaOH用量为大豆油量的1％、油醇摩尔比为1：6、搅拌时间为50min、反应温度为50～60℃、水的含量必须控制在油重的0．1％以下。     

车用柴油机燃用生物柴油的研究进展和发展前景

简要介绍了生物柴油的主要制备方法和燃料特性,综述了生物柴油对车用柴油机的低温起动性能、动力性、经济性,排放特性以及燃烧特性影响的研究进展,阐述了近期针对生物柴油研究的新对象和新方法,并探讨了生物柴油的应用前景。     

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.     

生物柴油转化效果测定方法的研究

生物柴油的生产原料、催化剂、工艺流程等存在多样化特点,为比较各种方法的优劣,需要建立一种适宜、通用的测定方法.通过分析国内外相关测定方法,提出以气相色谱测定反应产物,十七碳脂肪酸甲酯为标准物,内标法计算反应转化率和产率的方法.     

氨基磺酸非均相催化菜籽油及废油脂制备生物柴油

采用正交试验和单因素试验的方法研究了氨基磺酸催化菜籽油及废油脂与甲醇的酯交换过程,考察了醇油物质的量比、催化剂用量、反应温度和反应时间对反应收率的影响。结果表明:菜籽油酯交换的最佳反应条件为醇油物质的量比6∶1,氨基磺酸用量为原料油质量的1.0%,反应温度60℃,反应时间20 min,此工艺条件下,脂肪酸甲酯的收率达到95.6%;废油脂酯交换的最佳反应条件为醇油物质的量比8∶1,氨基磺酸用量为原料油质量的1.0%、反应温度65℃,反应时间30 min,此工艺条件下,脂肪酸甲酯的收率达到87.5%。利用红外光谱表征了菜籽油和生物柴油的结构,气相色谱分析了生物柴油的组成。     

Toward estimation of biodiesel production from castor oil using ANN

Nowadays, a green replacement for the conventional petrodiesel introduced as biodiesel in which its economical production way is using feedstock. Also, environmentally friendly fuels attracted more attention due to the serious global warming problem. In the present study, two different artificial intelligencebased modeling was utilized to predict the production of biodiesel from castor oil. Also, a comparison between the two methods was carried out, and the more applicable method for the prediction of biodiesel production was introduced. To this end, biodiesel production yield from castor oil assumed to be the target of the model and various parameters such as temperature (T), time (S), methanol to oil molar ratio, and catalyst weight (C) expected as input parameters. ANN modeling shows high accuracy and robustness for the prediction of biodiesel production, and statistical parameters such as coefficient of determination and root-mean-square error are 0.9984 and 1.13, respectively.     

制备生物柴油中超声空化过程的研究

建立了超声波辅助制备生物柴油中空化气泡运动的动力学模型,采用MATLAB对模型方程进行数值模拟,探讨超声频率、声压幅值、空化泡的初始半径和环境压力对空化泡运动的影响.模拟结果表明,随着超声波频率的增加,空化效应减弱;超声声压较小时,超声波空化为稳态空化过程,随着声压的增加,空化气泡半径变化幅度增加,空化气泡所带来的空化效应必然增加;气泡的原始半径为超声波频率对应的共振尺寸时,空化情况最为激烈,声化效果最好;环境压力变化时,气泡运动的振幅差别不大.经分析得到提高生物柴油产率的较佳条件,即较低频率、较大声压幅值、气泡直径为共振尺寸、普通大气压.该研究可为超声在制备生物柴油中的应用提供基础理论依据.     

A rapid ultrasound-assisted production of biodiesel from a mixture of Karanj and soybean oil

Karanj oil having high free fatty acid was neutralized with a dilute alkali solution and then mixed with soybean oil in different ratios in order to reduce the free fatty acid content significantly. The mixture of the oils was then transesterified with methanol to produce fatty acid methyl ester. The transesterification was carried out using ultrasonication energy of 20 kHz in pulse mode. It was found that up to 60% Karanj oil in the blended mixture could produce good quality biodiesel that met the ASTM standards. However, the lesser content of Karanj oil in the mixture, the lesser the reaction parameters viz. alcohol to oil molar ratio, catalyst concentration, and reaction time. About 99% yield of methyl esters was obtained when the Karanj oil content in the mixture was 20% with a reaction time of 30 min, catalyst concentration 1 wt%, and a temperature of 55°C.     

Ternary phase behavior of water microemulsified diesel-palm biodiesel

This paper aims to develop a new microemulsions system comprising diesel and palm oil methyl ester (PME) that have the potential to be used as alternative fuels for diesel engines. The water-in-diesel-biodiesel microemulsions were prepared by applying PME mixed with diesel, non-ionic surfactants, co-surfactants and water to make the water-in-oil (W/O) microemulsion system. This microemulsified fuel was achieved through low-energy microemulsification by using the constant composition method. The diesel used was mixed with four different concentrations of PME, i.e., 10% (w/w) (B10), 20% (w/w) (B20), 30% (w/w) (B30) and neat diesel (B0). The amount of water was fixed at 20% (w/w). The phase behavior of the water/mixed non-ionic surfactant/diesel-PME system were studied by constructing pseudoternary phase diagrams with the goal of formulating optimized systems. The results showed that the microemulsions were formed and stabilized with a mixture of non-ionic surfactants at a weight ratio of 80:20 at 20% (w/w), and with mixed co-surfactants at a weight ratio of 25:75, 20:80 and 10:90 for B0, B10, B20 and B30 respectively. The particle size, kinematic viscosity at 40°C, refractive index, density, heating value, cloud point, pour point and flash point of the selected water-in-diesel microemulsion were 19.40 nm (polydispersity of 0.12), 2.86 mm²/s, 1.435, 0.8913 g/mL, 31.87 MJ/kg, 7.15°C, 10.5°C and 46.5°C respectively. The corresponding values of the water-in-diesel-PME selected were 20.72 nm to 23.74 nm, 13.02 mm²/s to 13.29 mm²/s, 1.442, 0.8939 g/mL to 0.8990 g/mL, 31.45 MJ/kg to 27.34 MJ/kg, 7.2°C to 6.8°C, 8.5°C to 1.5°C and 47.5°C to 52.0°C. These preliminary findings were further studied as potential fuels for diesel engines.     

Potential hybrid feedstock for biodiesel production in the tropics

Recently, mixture of different oils at various proportions have been used as feedstock for biodiesel production. The primary aim is to improve fuel properties which are strongly influenced by the fatty acid composition of the individual oil that makes up the feedstock mix. The tropics are renowned for abundant oil-bearing crops of which palm kernel oil (PKO) from palm seed and groundnut oil (GNO) are prominent. This present paper investigated biodiesel production from hybrid oil (HO) of PKO (medium carbon chain and highly saturated oil) and GNO (long carbon chain and highly unsaturated oil) at 50/50 (v/v) blending. The principal fatty acids (FAs) in the HO are oleic (35.62%) and lauric acids (24.23%) with 47.80% of saturated FA and 52.26% of unsaturated FA contents. The chemical conversion of the oil to methyl ester (ME) gave 86.56% yield. Fuel properties of hybrid oil methyl ester (the HOME) were determined in accordance with standard test methods and were found to comply with both ASTM D6751 and EN 14214 standards. The oxidative stability, cetane number and kinematic viscosity (KV) of HOME were observed to be improved when compared with those of GNO methyl ester from single parent oil, which could be accredited to the improved FA composition of the HO. The KV (3.69 mm²/s) of HOME obtained in this paper was remarkably low compared with those reported in literature for most biodiesels. This value suggests better flow, atomization, spray and combustion of this fuel. Conclusively, the binary blend of oils can be a viable option to improve the fuel properties of biodiesel feedstock coupled with reduced cost.