碳基固体酸催化废弃油脂合成脂肪酸甲酯

在碳基固体酸催化下,废弃油脂与甲醇反应合成生物柴油。系统考察了反应时间、甲醇与废弃油脂的配比、碳基固体酸用量及催化剂重复使用等因素对反应的影响。结果表明,具有疏水表面的碳基固体酸对废弃油脂与甲醇的反应具有很好的催化性能,可以一步同时催化废弃油脂中的游离脂肪酸与甲醇的甲酯化以及甘油三酯与甲醇的酯交换反应,具有反应条件温和,催化活性高等优点。     

固体复合酸催化废弃油脂预酯化反应的研究

利用废弃油脂作为原料油制备生物柴油是一条符合我国国情的方法,但一般废弃油脂酸值高,因此在碱催化酯交换反应之前,需对高酸值原料油进行降酸处理.考察了相关条件对油脂预酯化反应的影响,并通过正交实验和数据分析,得到最佳条件为固体酸用量3%、醇油摩尔比6∶1、反应温度80℃、反应时间2 h.同时研究了不同酸值原料油在固体酸催化作用下的酯化率.     

微波辐射酸催化潲水油合成生物柴油的研究

本文研究了以H2SO4为催化剂,以潲水油和甲醇为原料,在微波辐射下直接进行酯交换合成生物柴油的方法.通过实验得出最佳反应条件为:醇酸摩尔比为25:1,催化剂用量为油重的2%,微波辐射功率为480W,辐射90min,在此条件下取得了较好的酯交换率.     

复合固定化脂肪酶催化餐厨废弃油脂合成生物柴油

探讨了复合固定化脂肪酶(Rhizopus oryzae lipase和Candida rugosa lipase)催化餐厨废弃油脂合成生物柴油的工艺条件。实验结果表明,单独使用1,3位专一性脂肪酶R.oryzae lipase催化餐厨废弃油脂,反应18h,生物柴油转化率达到70%;单独使用非专一性脂肪酶C.rugosa lipase,反应30h,生物柴油转化率可达20%。为了更有效提高生物柴油转化率,采用1,3位专一性脂肪酶R.oryzae lipase和非专一性脂肪酶C.rugosa lipase复合固定化脂肪酶催化合成生物柴油,反应21h,生物柴油转化率可达到96.5%。同时对该复合酶的稳定性进行了实验,在连续催化反应10个批次(300h)后,生物柴油转化率仍保持在80%以上。     

废弃油脂超临界法制备生物柴油研究

以废弃油脂为原料,利用超临界法制备生物柴油.通过单因素实验及正交实验研究了醇油摩尔比、反应压力、催化剂用量、反应时间、反应温度等因素对生物柴油产率的影响.结果表明,在实验范围内各影响因素对生物柴油产率作用的大小依次为:反应温度>反应压力>催化剂用量>反应时间>醇油摩尔比.废弃油脂超临界法制备生物柴油的最佳工艺条件为:反应温度240℃,反应压力10MPa,反应时间6min,催化剂用量0.06%,醇油摩尔比40/1.在此条件下,生物柴油产率达到99.37%.     

从废弃油脂生物柴油中分离不饱和脂肪酸甲酯

以废弃油脂制生物柴油为原料,以95%醇为溶剂,采用尿素包合法提取不饱和脂肪酸甲酯,为生物柴油联产具有高附加值化工产品打下基础.重点考察了尿素用量、溶剂用量、包合时间和包合温度对不饱和脂肪酸甲酯分离效果的影响.结果表明,尿素包合法从生物柴油中分离不饱和脂肪酸甲酯的适宜工艺条件为:尿素,生物柴油质量比为1.4～1.7,溶剂/生物柴油质量比为4.6～6.0,包合温度为10℃,包合时间为18 h.在适宜条件下,不饱和脂肪酸甲酯含量可达93.5%,收率可达55.8%.     

固体酸催化油脂酯交换制备生物柴油

综述了固体酸催化制备生物柴油的优势、机理及研究进展,对固体酸催化制备生物柴油的研究方向进行了展望.     

高酸值废弃油脂制备生物柴油的预酯化

为了有效解决现有酯化体系中存在反应慢、时间长、产能低等问题,提出了一种高温下甲醇连续酯化反应的新技术,并采用该技术以对甲苯磺酸为催化剂催化高酸值废弃油脂预酯化试验研究。系统讨论了不同酯化方法对反应的影响,并着重研究了工艺条件对预酯化效果的影响。实验结果表明:高温下甲醇连续酯化的新技术可显著提高酯化反应效率,在反应温度120℃、甲醇流量4.0mL/min、催化剂加入量0.8%的条件下,酯化率达98.8%以上,可将油脂的酸值降至1.0mgKOH/g以下,满足下一步酯交换制备生物柴油的要求;并基于实验研究的基础上将该技术工艺对不同酸值的废弃油脂进行了放大试验研究,皆取得了较好的酯化效果,为产业化、规模化的应用提供理论依据和参数指导。     

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。     

固定化脂肪酶催化废油合成生物柴油

研究了固定化假丝酵母99-125脂肪酶在有溶剂的体系下催化废油合成生物柴油过程中,油醇摩尔比、有机溶剂性质、底物浓度、体系含水量、甲醇流加等因素对反应过程的影响.研究结果表明,在最佳实验条件下,反应转化率最高可达92％,酶的使用寿命可达7批以上.     

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%。     

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.     

废油脂预处理及制备生物柴油研究进展

介绍了废油脂的预处理工艺及我国废油脂的现状,重点阐述了国内外以废油脂为原料经碱法、酸法和酶法酯交换制备生物柴油的研究情况,并对目前存在的问题和相应的解决对策进行了简单的讨论。     

炭基固体酸催化废油脂合成生物柴油动力学研究(英文)

The kinetics of simultaneous transesterification and esterification with a carbon-based solid acid catalyst was studied.Two solid acid catalysts were prepared by the sulfonation of carbonized vegetable oil asphalt and petroleum asphalt.These catalysts were characterized on the basis of elemental analysis,acidity site concentration,the Brunauer-Emmett-Teller(BET)surface area and pore size.The kinetic parameters with the two catalysts were determined,and the reaction system can be described as a pseudo homogeneous catalyzed reaction.All the forward and reverse reactions follow second order kinetics.The calculated concentration values from the kinetic equations are in good agreement with experimental values.     

Transesterification for biodiesel production catalyzed by combined lipases: Optimization and kinetics

Preparation of biodiesel from waste cooking oil catalyzed by combined lipases in tert‐butanol medium was investigated. Several crucial parameters affecting biodiesel yield were optimized by response surface methodology, such as dosage of combined lipases of Novozym 435 and Lipozyme TLIM, weight ratio of Novozym 435 to Lipozyme TLIM, amount of tert‐butanol, reaction temperature, and molar ratio of oil to methanol. Under the optimized conditions, the highest biodiesel yield was up to 83.5% The proposed model on biodiesel yield had a satisfactory coefficient of R² (= 94.02%), and was experimentally verified. The combined lipases exhibited high‐operational stability. After 30 cycles (300 h) successively, the activity of combined lipases maintained 85% of its original activity. A reaction kinetic model was proposed to describe the system and deduced to be a pseudo‐first‐order reaction, and the calculated activation energy was 51.71 kJ/mol. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

碘催化餐饮废油合成生物柴油

以餐饮废油脂为原料,先用硅藻土对其进行脱色,再在I2的催化作用下,用已脱色的餐饮废油为原料合成生物柴油。并考察了反应温度,反应时间,醇油比和催化剂用量4个因素对产量的影响,得到了利用餐饮废油合成生物柴油的工艺条件：反应温度为60℃,反应时间为2h,醇油比为2∶1,催化剂用量为1.3%。在最佳工艺条件下,生物柴油的收率为58.8%。     

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。