叔丁醇共溶剂用于制备生物柴油的研究

利用叔丁醇作为共溶剂可使棕榈油、甲醇和催化剂形成均相体系,用于酯交换反应制备生物柴油,可以缩短反应时间。实验以棕榈油为原料,氢氧化钠为催化剂,在带夹套的玻璃反应器内进行反应。考察了共溶剂质量分数、催化剂质量分数、反应温度、醇油摩尔比等因素对生物柴油产率的影响,获得了最佳反应条件。实验结果表明,当叔丁醇质量为棕榈油质量的11.6%,催化剂质量为油质量的1.0%,反应温度为60℃,醇油摩尔比为6∶1时,反应2 m in后生物柴油产率达到了90%。     

棕榈油酯交换制备生物柴油的反应动力学

在甲醇与棕榈油的摩尔比为6∶1和催化剂KOH用量为棕榈油质量1.0%的条件下,研究不同温度下棕榈油制备生物柴油的酯交换反应动力学,采用Origin软件拟合曲线方程,建立棕榈油酯交换反应的宏观动力学模型。研究结果表明:棕榈油制备生物柴油的酯交换反应遵循1.40级动力学方程,反应速率随温度的升高而加快,二者符合Arrhenius方程,该反应的活化能为27.23 kJ/mol,频率因子为1.4×103。文中研究建立的反应动力学模型将对扩大试验研究提供理论依据和基础数据支持。     

Effect of altitude and palm oil biodiesel fuelling on the performance and combustion characteristics of a HSDI diesel engine

Altitude above sea level and fuel’s chemical and physical nature affect engine performance and combustion characteristics. In this work, a combustion diagnosis model including exergy analysis was applied to a turbocharged (TC) automotive diesel engine fuelled with neat palm oil biodiesel (B100) and No. 2 diesel fuel (B0). Tests were performed under steady state operating conditions, at two altitudes above sea level: 500 and 2400 m. Biodiesel fuelling and altitude had an additive effect on the advance in injection and combustion timings. The duration of the premixed combustion stage increased with altitude and decreased with biodiesel. When B100 was used, the transition between this stage and the diffusion stage was practically suppressed. As altitude increased, biodiesel fuelling led to shorter combustion duration, and higher in-cylinder pressures and fuel-air equivalence ratios. Brake thermal efficiency decreased with altitude for both fuels, but in a greater extent for B0. For all fuels and altitudes, exergy destruction rose sharply when combustion started, indicating that this process was the main source of irreversibilities. At both altitudes, the cumulative exergy destruction was higher for B100 due to its earlier and faster combustion process. Some of the results obtained in this work indicate that palm oil biodiesel fuelling can lead to a better engine performance at high altitudes.     

微碱强化超临界法制备生物柴油组分分析及工艺过程

对超临界条件下添加微量氢氧化钾催化碳酸二甲酯与棕榈油制备无甘油副产的生物柴油反应进行了研究,微碱的添加有效降低了苛刻的反应条件。利用气质联用技术对反应产物的组分进行了定性确证并建立了产物的定量分析方法。结果表明,酯交换反应的产物组分为甘油碳酸酯、脂肪酸甲酯、甘油单酯、脂肪酸甘油碳酸酯、甘油二酯和甘油三酯。考察了反应温度、反应时间、酯油摩尔比以及催化剂添加量对酯交换反应的影响。当反应温度280℃、反应时间20 min、KOH添加量为0.1%、酯油摩尔比20:1、反应压力3.5MPa时,脂肪酸甲酯的收率可达到83.11%。     

Ignition delay in a palm oil and rapeseed oil biodiesel fuelled engine and predictive correlations for the ignition delay period

This paper presents the results of engine tests of biodiesels obtained by transesterification of palm oil and rapeseed oil and with fossil diesel fuel as a reference. The analysis is focused on the determination of the ignition delay and on obtaining a predictive correlation for it. The experiments show no significant difference in in-cylinder pressures at injection timing for each fuel. With biodiesel slightly lower peak cylinder pressures were observed for most engine conditions. Palm oil and rapeseed oil biodiesel gave shorter ignition delay than fossil diesel fuel due to the higher cetane number for the biodiesels. The ignition delay data were correlated as a function of the equivalence ratio, the mean cylinder pressure and mean temperature over the ignition delay interval. A comparison is made with other available correlations. The ignition delay values estimated by the new correlations are in good agreement with the experiments.     

全球生物柴油产业的发展

在全球市场上,马来西亚正在逐步上升为生物柴油的最主要出口国。介绍了生物柴油在马来西亚的发展状况以及市场前景,同时对全球主要生物柴油生产国的现状做了简要分析,指出在繁荣的背景下存在的问题。     

生物柴油低温流动改进剂复配研究

采用碱催化法制备菜籽油生物柴油和棕榈油生物柴油,对其主要品质指标进行分析;考察了添加不同的柴油低温流动改进剂及其复配物对生物柴油低温流动性能的影响。结果表明,柴油低温流动改进剂能够改善生物柴油低温流动性能;将其进行复配后,能表现出协同效应,取得更好的降滤效果,尤其能使饱和脂肪酸甲酯含量高的棕榈油生物柴油冷滤点降低8℃;不同生物柴油对柴油低温流动改进剂或其复配物感受性存在较大差异,不饱和脂肪酸甲酯含量高,且脂肪酸甲酯种类较多、分布较广的菜籽油生物柴油对单一低温流动改进剂感受性好,而饱和脂肪酸甲酯含量高,且脂肪酸甲酯种类分布较集中的棕榈油生物柴油对复配物感受性好。     

生物柴油氧化安定性的实验室研究

用桐油生物柴油、棕榈油生物柴油和石化柴油以不同的比例混和分别放置在不同的条件下常温贮存3×30 d,对其氧化安定性进行考察,定时取样测其过氧化值、酸值、运动粘度。并对得出的变化规律进行总结分析,以求将双键较多的生物柴油应用的更加广泛。     

菜籽油制备生物柴油的研究现状和发展趋势

综述了国内外以菜籽油制备生物柴油的研究现状和发展趋势,通过对各种制备方法的系统比较和国内外发展现状的考察,提出了用常压、连续反应-分离一体化的生产技术,以纳米固体酸、碱催化法制备生物柴油的研发方向,指出了以菜籽油为原料制备生物柴油的发展优势。     

生物柴油浸没喷吹的雾化特性

以生物柴油替代柴油进行浸没喷吹熔池熔炼是发展低碳铜冶炼的重要途径。针对该过程建立生物柴油浸没喷吹雾化流动过程计算模型,本文模拟计算了喷枪在水模型中浸没深度为20mm时不同油气比条件下生物柴油雾化颗粒的雾化特性,并实验验证了计算模型。研究结果表明：油滴颗粒的贯穿距随着空气流速的增加而增大;在气泡内油滴颗粒以一定的雾化半角向前扩散;当油滴颗粒到达气泡底部时,油滴颗粒以气泡底部平面为中心向整个空间扩散;气泡内距离喷枪轴向越远的观察面内大颗粒数目越多;油滴颗粒的索特平均直径（SMD）沿喷枪轴向先增大后减小;气泡内距喷枪口越远油滴颗粒SMD越大,进入水区域的油滴颗粒SMD逐渐减小;雾化空气流速越大,油滴颗粒SMD最大值的位置距喷口越远。     

Performance of compression ignition engine with mahua (Madhuca indica) biodiesel

The performance of biodiesel obtained from mahua oil and its blend with high speed diesel in a Ricardo E6 engine has been presented in this paper together with some of its fuel properties. These properties were found to be comparable to diesel and confirming to both the American and European standards. Engine performance (brake specific fuel consumption, brake thermal efficiency and exhaust gas temperature) and emissions (CO, smoke density and NO_x) were measured to evaluate and compute the behaviour of the diesel engine running on biodiesel. The reductions in exhaust emissions and brake specific fuel consumption together with increase brake power, brake thermal efficiency made the blend of biodiesel (B20) a suitable alternative fuel for diesel and thus could help in controlling air pollution.     

微波强化棉籽油制备生物柴油的研究

利用微波强化以棉籽油和甲醇为原料,KOH为催化剂制备生物柴油。考察醇油摩尔比、催化剂用量、反应时间和微波功率对酯交换反应的影响。结果表明,醇油摩尔比为9∶1,催化剂用量为1.0%,反应时间为3 min,微波功率360 W为最优反应条件。在此反应条件下生物柴油产率可达94%。与传统合成方法相比,该方法可缩短反应时间30~35 min。所得生物柴油主要质量指标达到我国和欧洲(EN14214)生物柴油质量标准,通过红外光谱分析表明,棉籽油生物柴油具有生物柴油所含的官能团。     

超临界制备生物柴油及副产甘油工艺研究

利用植物油和超临界甲醇制备生物柴油及副产甘油,增加了油相在其中的溶解度,提高了原料转化率和产品收率。实验考察了醇油摩尔比、压力、温度、时间等对生物柴油及副产物甘油产率的影响,结果表明:醇油摩尔比、压力、温度、时间等因素对生物柴油及甘油产率影响较为显著。通过正交实验设计得出的超临界甲醇制备生物柴油的工艺条件为醇油摩尔比30∶1,压力20 MPa,温度280℃,保温时间60 m in,生物柴油和甘油产率可分别达到89.14%和88.73%。     

Palm fatty acid biodiesel: process optimization and study of reaction kinetics

The relatively high cost of refined oils render the resulting fuels unable to compete with petroleum derived fuel. In this study, biodiesel is prepared from palm fatty acid (PFA) which is a by-product of palm oil refinery. The process conditions were optimized for production of palm fatty acid methyl esters. A maximum conversion of 94.4% was obtained using two step trans-esterification with 1:10 molar ratio of oil to methanol at 65°C. Sulfuric acid and Sodium hydroxide were used as acid and base catalyst respectively. The composition of fatty acid methyl esters (FAME) obtained was similar to that of palm oil. The biodiesel produced met the established specifications of biodiesel of American Society for Testing and Materials (ASTM). The kinetics of the trans-esterification reaction was also studied and the data reveals that the reaction is of first order in fatty acid and methanol (MeOH) and over all the reaction is of second order.     

Metakaolinite as a catalyst for biodiesel production from waste cooking oil

The use of metakaolinite as a catalyst in the transesterification reaction of waste cooking oil with methanol to obtain fatty acid methyl esters (biodiesel) was studied. Kaolinite was thermally activated by dehydroxylation to obtain the metakaolinite phase. Metakaolinite samples were characterized using X-ray diffraction, N₂ adsorption-desorption, simultaneous thermo-gravimetric analyse/differential scanning calorimetry (TGA/DSC) experiments on the thermal decomposition of kaolinite and Fourier-transform infrared spectrometer (FTIR) analysis. Parameters related to the transesterification reaction, including temperature, time, the amount of catalyst and the molar ratio of waste cooking oil to methanol, were also investigated. The transesterification reaction produced biodiesel in a maximum yield of 95% under the following conditions: metakaolinite, 5 wt-% (relative to oil); molar ratio of oil to methanol, 1∶23; reaction temperature, 160°C; reaction time, 4 h. After eight consecutive reaction cycles, the metakaolinite can be recovered and reused after being washed and dried. The biodiesel thus obtained exhibited a viscosity of 5.4?mm²?s^–1 and a density of 900.1 kg?m^–3. The results showed that metakaolinite is a prominent, inexpensive, reusable and thermally stable catalyst for the transesterification of waste cooking oil.     

粗菜籽油制备生物柴油及放大实验研究

为了考察项目组自行开发的新型催化剂(SXL)的催化效率,以粗菜籽油为原料,SXL为催化剂,酯交换反应为基础,研究产物生物柴油的转化率和产率。结果表明:小试优化反应条件以100 g粗菜籽油为原料油、醇油比(摩尔比)7∶1、催化剂用量(质量分数)为2.5%、反应温度为60℃、反应时间为2 h下,生物柴油转化率和产率均达到98%以上。放大实验结果:在20 L反应釜中,投入6.50 kg粗菜籽油,以小试条件为基础,原料油转化率、生物柴油产率和甘油产率可达95%以上。表明SXL具有良好的发展前景。     

茶油精炼副产物皂脚制备生物柴油的研究

以茶油精炼副产物皂脚和甲醇为原料,NaOH为催化剂,经酯交换合成生物柴油,研究了工艺条件对皂脚合成生物柴油收率的影响。结果表明,适宜的工艺条件为:醇油摩尔比为5∶1,反应时间为30 min,反应温度为30℃,催化剂NaOH用量为油重的0.7%,反应收率为98.0%。     

Some physical properties and oxidative stability of biodiesel produced from oil seed crops

Biodiesel is a cleaner burning fuel than petrodiesel and a suitable replacement in diesel engine. It is produced from renewable sources such as vegetable oils or animal fats. Biodiesel fuel was prepared from castor (CSO), palm kernel (PKO) and groundnut (GNO) oils through alkali transesterification reaction. The biodiesel produced was characterized as alternative diesel fuel. Fuel properties such as specific gravity, viscosity, calorific (combustion) value, The CSO, PKO and GNO were measured to evaluate the storage/oxidative stability of the oils to compare them with commercial petrodiesel. The biodiesel produced had good fuel properties with respect to ASTM D 6751 and EN 14214 specification standards, except that the kinematic viscosity of castor oil biodiesel was too low. The viscosity of castor oil biodiesel at different temperatures was in the range of 4.12–7.21 mm²/s. However, promising results which conformed to the above specification standards were realized when castor oil biodiesel was blended with commercial petrodiesel. At 28 °C the specific gravity recorded for CSO, PKO and GNO biodiesel was higher than the values obtained for petrodiesel. Commercial petrodiesel had the highest oxidative stability than biodiesel produced from CSO, PKO and GNO oils.     

Solution polymerization of styrene using biodiesel as a solvent: Effect of biodiesel feedstock

Increasing environmental concerns regarding solvents commonly used in solution polymerization has led to a search for alternatives, such as biodiesel (a.k.a. fatty acid methyl esters or FAME). The effect of the feedstock used in biodiesel production when FAME is used as a polymerization solvent was studied for styrene. A series of homopolymerizations was carried out at different solvent concentrations for two biodiesel feedstocks: soybean oil and 50% yellow grease–50% canola oil. Results were compared to FAME produced from canola oil. Considerable differences in the rate of polymerization were observed, while chain transfer to solvent constants had comparable values. The collected kinetic experimental data were modelled using a polymerization simulator.     

微藻产生物柴油研究进展

微藻是地球上生长最快的植物,利用含油微藻作为生物柴油的原料来源是生物燃料产业最具竞争力的选择之一。本文首先介绍了含油微藻制备生物柴油的工艺过程,然后对产油微藻的筛选、微藻培养系统、微藻的收集分离、藻油的提取、微藻油脂制生物柴油过程分别进行了阐述,其中就用于微藻规模化培养的循环渠开放系统和各种光生物反应器的封闭系统进行了较为详细的讨论,指出了各种系统的优缺点和最新研究进展。最后,就微藻产生物柴油产业的发展趋势和研发方向提出了建议。