微波辐射印楝油甲酯化响应曲面模型研究

以微波辐射印楝油甲酯化制取生物柴油,通过单因素实验,找到醇油物质的量比、催化剂用量、反应温度和反应时间的较佳取值范围。根据Box-Behnken实验设计原理设计实验,以印楝油转化率为响应值,建立反应的回归模型,进行响应面分析和优化。结果表明,微波辐射印楝油甲酯化反应的最佳工艺条件为:醇油物质的量比5.4∶1,催化剂KOH用量1.36%,反应温度50℃,反应时间68 min。在此条件下,印楝油的转化率为93.17%,与理论预测值93.78%的相对误差为0.65%。     

Microwave irradiation-assisted transesterification of soybean oil to biodiesel catalyzed by nanopowder calcium oxide

This study examined the effect of a heterogeneous base catalyst on the transesterification of soybean oil assisted by microwave irradiation. The results showed that nanopowder calcium oxide (nano CaO) was very efficient in converting soybean oil to biodiesel, and microwave irradiation is more efficient than the conventional bath for biodiesel production. However, the water content of methanol can not improve the conversion rate catalyzed by nano CaO.The suitable reaction conditions that can reach a 96.6% of conversion rate were methanol/oil molar ratio, 7:1; amount of catalyst used, 3.0 wt.%; reaction temperature, 338 K; and reaction time, 60 min. The biodiesel produced is within the limits prescribed by the standard of EN-14214.     

负载型固体碱催化合成甲酯生物柴油的研究

采用浸渍法制备了Na2CO3/高岭土负载型固体碱催化剂,用于催化大豆油与甲醇酯交换反应制备甲酯生物柴油。考察了反应时间、催化剂用量、反应温度和醇油摩尔比对酯交换反应转化率的影响,并通过单因素试验确定了最优工艺条件。结果表明:反应时间4 h、反应温度60℃、催化剂用量3%和醇油摩尔比12∶1条件下,酯交换反应转化率达到90.5%。     

微波辐射酸催化喜树种子油制备生物柴油工艺

研究了在微波辐射条件下硫酸催化酯交换反应转化喜树种子油制备生物柴油的工艺,同时采用HPLC分析了生物柴油产品中主要脂肪酸甲酯成分及其质量分数。通过实验考察了醇油摩尔比、反应时间、反应温度、催化剂加入质量分数对反应的影响,并得出了在微波辐射下硫酸催化喜树种子油制备生物柴油的最佳工艺条件:醇油摩尔比15∶1、微波辐射时间40 min、反应温度70℃、催化剂加入质量分数(与原料油)3%,转化率可达95%以上。结果表明,与传统硫酸催化酯交换反应相比,该方法具有催化剂加入质量分数少、反应温度低、时间短和转化率高等优点,对工业化制备生物柴油提供了科学参考价值。     

Na_2CO_3/MCM-41型固体碱催化制备生物柴油

以MCM-41为载体负载Na2CO3制备Na2CO3/MCM-41型酯交换催化剂,用于催化大豆油制备生物柴油。并研究了催化剂用量、反应物的摩尔比、反应温度和反应时间等因素对该反应的影响。结果表明,最佳反应条件是n(甲醇)∶n(大豆油)=16∶1,催化剂用量为大豆油质量的3%,反应温度为60℃,反应时间为3 h条件下,酯交换转化率可达35%以上。     

微波辅助合成α-萘乙酸甲酯的研究

在微波辐射下,以浓H2SO4为催化剂、α-萘乙酸和甲醇为原料合成α-萘乙酸甲酯。考察了微波辐射时间、醇酸比、催化剂用量对α-萘乙酸甲酯产率的影响。实验结果表明,最佳实验条件为：微波辐射时间4.5 min（功率700W）,醇酸物质的量比10∶1,催化剂为总质量的9.2%,产率为94.4%。探讨了微波辅助下,酯化反应的可能机理。     

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。     

Optimization of biodiesel production from crude palm oil using ultrasonic irradiation assistance and response surface methodology

BACKGROUND: Production of biodiesel from crude palm oil (CPO) with 6 wt% of free fatty acid (FFA) using a low‐frequency ultrasonic irradiation (40 kHz) technique was investigated in the present work. The objective of this study was to determine the relationship between various important parameters of the alkaline catalyzed transesterification process to obtain a high conversion to biodiesel. Response surface methodology (RSM) was used to statistically analyze and optimize the operating parameters of the process. A central composite design (CCD) was adopted to study the effects of the methanol to oil molar ratio, the catalyst concentration, reaction temperature, and irradiation time on conversion to biodiesel. RESULTS: The result from the RSM analysis indicated that the methanol to oil molar ratio, catalyst concentration and irradiation time have the most significant effects on the conversion to biodiesel. Moreover, a coefficient of determination (R²) value of 0.93 shows the fitness of a second‐order model for the present study. Based on this second‐order model, the optimum conditions for alkaline catalyzed transesterification of CPO were found to be a methanol to oil molar ratio of 6.44:1, catalyst concentration 1.25 wt%, reaction temperature 38.44 °C and irradiation time 25.96 min. At the calculated optimum condition, the conversion to biodiesel reached 97.85%. Under these same conditions, the experimental value was 98.02 ± 0.6%. CONCLUSIONS: The mathematical model developed has been proven to adequately describe the range of the experimental parameters studied and provide a statistically accurate prediction of the optimum conversion to biodiesel. Copyright © 2011 Society of Chemical Industry     

微波辐射下二丁基锡（Ⅳ）对氨基苯磺酸酯催化合成对羟基苯甲酸异戊酯

以二丁基氧化锡和对氨基苯磺酸为原料合成了二丁基锡（IV）对氨基苯磺酸酯,并以此为催化剂,在微波辐射下合成了对羟基苯甲酸异戊酯。探讨了微波功率、催化剂用量、反应时间、温度及醇酸摩尔比对酯合成收率的影响。结果表明,该有机锡化合物在微波辐射下对酯化反应有良好的催化活性,在辐射功率为550 W,辐射时间为40 min,催化剂用量为0.5 g,醇酸摩尔比为5∶1,反应温度为110℃的条件下,对羟基苯甲酸异戊酯的收率可达94%。     

乙醇与餐饮废油制备生物柴油的工艺研究

以餐饮废油和乙醇为原料,以氢氧化钾为催化剂,采用酯交换法制备生物柴油。考查了醇油摩尔比、催化剂用量、反应时间和温度对原料转化率的影响。正交试验结果表明,餐饮废油与乙醇酯交换反应的最佳反应条件为：醇油摩尔比12∶1,催化剂用量1.25%,反应温度78℃,反应时间1.5h。在此反应条件下,餐饮废油转化率达65.12%;在此基础上引入四氢呋喃作助溶剂,转化率可提高至86%~90%。     

橄榄油制备生物柴油的工艺研究

以橄榄油为原料,四氢呋喃作共溶剂,NaOH为催化剂制备生物柴油.用气相色谱分析方法,通过对反应温度、醇油摩尔比、催化剂的量、反应时间的研究,得出在各自的最优化条件下橄榄油的转化率为97.3%.     

双液相萃取棉籽油制备脂肪酸甲酯

以双液相萃取技术处理棉籽，在得到脱毒棉粕的同时得到含有高质量毛油的非极性相。以非极性相作为与甲醇进行酯交换反应的原料，得到脂肪酸甲酯和甘油。考察了非极性相溶剂石油醚与棉籽油的比例对酯交换转化率和洗涤粗产品用水量的影响，确定了石油醚与棉籽油的最佳质量比为3，在此条件下，洗涤用水量可降低一半。考察了醇油比、催化剂用量、反应温度、反应时间等参数对转化率的影响。应用正交实验的方法找出酯交换反应的适宜条件为：醇油比6：1，催化剂用量1.1％，反应温度60℃，反应时间120min。在此反应条件下，产物中脂肪酸甲酯的含量可达97.4％。     

Production of bio-diesel fuels by transesterification of rice bran oil

Transesterification of rice bran oil was investigated to produce the bio-diesel oil. Experimental conditions included molar ratio of rice bran oil to alcohol (1:3, 1:5 and 1 :7), concentration of catalyst used (0.5, 1.0 and 1.5 wt%), types of catalysts (sodium methoxide, NaOH and KOH), reaction temperatures (30, 45 and 60°C) and types of alcohols (methanol, ethanol and butanol). The conversion of rice bran oil increased with the alcohol mixing ratio and with the reaction temperature. Sodium methoxide was the most effective among the catalysts. The conversion was increased with the concentration of catalyst, but slightly increased over 1.0 wt%. The best conversion was obtained using methanol with sodium methoxide. In that case, 98% conversion was achieved within 1 hr. The physical properties of rice bran oil for diesel fuel can be significantly improved by transesterification reaction.     

Biodiesel from an alkaline transesterification reaction of soybean oil using ultrasonic mixing

The feasibility of using ultrasonic mixing to obtain biodiesel from soybean oil was established. The alkaline transesterification reaction was studied at three levels of temperature and four alcohol-to-oil ratios. Excellent yields were obtained for all conditions. For example, at 40°C with ultrasonic agitation and a molar ratio of 6∶1 methanol/oil, the conversion to FAME was greater than 99.4% after about 15 min. For a 6∶1 methanol/oil ratio and a 25 to 60°C temperature range, a pseudo second-order kinetic model was confirmed for the hydrolysis of DG and TG. Reaction rate constants were three to five times higher than those reported in the literature for, mechanical agitation. We suspect that the observed mass transfer and kinetic rate enhancements were due to the increase in interfacial area and activity of the microscopic and macroscopic bubbles formed when ultrasonic waves of 20 kHz were applied to a two-phase reaction system.     

超声波促进浓H2SO4改性活性炭催化合成β-萘甲醚

在超声波辐射下,以活性炭负载浓硫酸作催化剂,催化合成了β-萘甲醚。考察了超声波辐射功率、辐射时间、无水甲醇用量、催化剂用量等因素对合成工艺的影响。确定了最佳反应条件:n(β-萘酚)∶n(无水甲醇)=1∶6,x(催化剂)=7%,超声波辐射功率200W,反应时间为15min,反应温度为80℃,在该条件下,β-萘甲醚产率为98.3%。该方法条件温和、操作简便高效。     

超声作用下碱催化大豆油酯交换反应制备生物柴油

采用低频率超声（40kHz）强化KOH催化大豆油和甲醇酯交换反应制备了生物柴油。结果表明,超声空化作用的传质和乳化效果较传统机械搅拌作用显著。不同超声功率对酯交换反应的强化作用不同,超声功率60-80W对生物柴油制备影响显著。此外,超声作用下酯交换反应时间大大缩短,催化剂和甲醇的用量也有所减少。在催化剂用量为1．0％、醇油摩尔比为6：1、45℃水浴条件下,超声作用10min,甲酯含量高达99％。     

Production of biodiesel through transesterification of Jatropha oil using KNO3/Al2O3 solid catalyst

The purpose of the work to study biodiesel production by transesterification of Jatropha oil with methanol in a heterogeneous system, using alumina loaded with potassium nitrate as a solid base catalyst. Followed by calcination, the dependence of the conversion of Jatropha oil on the reaction variables such as the catalyst loading, the molar ratio of methanol to oil, reaction temperature, agitation speed and the reaction time was studied. The conversion was over 84% under the conditions of 70 °C, methanol/oil mole ratio of 12:1, reaction time 6 h, agitation speed 600 rpm and catalyst amount (catalyst/oil) of 6% (w). Kinetic study of reaction was also done.     

微波促进下新型碳基固体酸催化合成草酸酯

在微波辐射条件下,以新型碳基固体酸为催化剂催化草酸分别与正丁醇、异丁醇、正戊醇、异戊醇的酯化反应。系统研究了微波功率、酸醇摩尔比、催化剂用量、反应时间等诸因素对酯化率的影响。实验结果表明：微波功率为500 W,在n（醇）/n（酸）=4.0︰1,催化剂用量占反应物料总质量的2.3%,反应时间为12 min条件下,不同草酸酯的酯化率均在95%以上。该固体酸重复使用多次,其催化活性基本不变。     

油酸甲酯烯烃复分解合成1-癸烯的工艺优化

以油酸甲酯（MO）为植物油脂模型物,通过烯烃复分解反应制备1-癸烯,以油酸甲酯转化率和1-癸烯得率为评价指标,探究了反应底物、催化剂类型、反应温度、反应时间、催化剂用量和MO与反应底物物质的量之比对烯烃复分解反应制备1-癸烯的影响,最后通过正交试验设计优化得到最佳工艺条件。结果表明：反应底物丁香酚和Grubbs第二代催化剂C2有利于本反应体系,最佳工艺条件为反应温度0℃,反应时间40 min,催化剂C2用量1%,n（MO）：n（丁香酚）1：10,在此条件下MO转化率和1-癸烯得率分别为96%和78%。     

新型固体碱铝酸钙催化剂用于生物柴油的制备研究

采用化学合成法制备了铝酸钙固体催化剂,并将其用于菜籽油与甲醇酯交换反应的研究.考察了酯交换反应的条件,实验结果表明,当醇/油摩尔比为15:1,催化剂质茸分数6%,反应温度65℃,搅拌速率270 r/min,反应时间3 h,甲酯的收率为89.05%.产物和催化剂固液分离简单容易,铝酸钙固体催化剂具有较好的稳定性,连续使用7次,甲酯的收率均在87.00%以上.同时采用Hammett指示剂法、XRD、BET等手段对铝酸钙同体催化剂进行了表征.