正交法探讨制备生物柴油的优化条件

植物油在NaOH为催化剂的作用下通过甲醇酯交换反应生成脂肪酸甲酯(生物柴油)。考察了反应条件如醇油比、催化剂用量、反应温度、反应时间等的变化对生物柴油得率的影响。应用正交实验的方法找出植物油酯交换反应的最佳反应条件为:反应温度40℃,醇油物质的量比6∶1,催化剂用量0.8%,反应时间60 min。在此反应条件下生物柴油得率可达99.2%。实验所得的生物柴油主要质量指标已达到德国DINV51.606生物柴油质量标准。     

生物柴油酯交换反应机理和影响因素分析

阐述了生物柴油的生产制备技术,从生物柴油酯交换合成反应出发,探讨了原料油中水分和游离脂肪酸、醇油比、温度、压力、催化剂、反应时间、原料混合程度等各因素对制备生物柴油的影响,分析了各种酯交换反应的反应机理;得出了酯交换反应制备生物柴油的最佳反应工艺条件。     

棉籽油制备生物柴油的研究

采用棉籽油为原料,在催化剂(KOH)的作用下,通过甲醇酯交换反应制备生物柴油;考察了醇油比、催化剂用量、反应温度、反应时间对生物柴油收率的影响;确定了棉籽油酯交换反应的适宜反应条件:醇油物质的量比6:1,催化剂用量1.2%,反应温度60℃,反应时间30 min,在此条件下,柴油收率为96.3%,其质量指标密度、牯度、甲酯和硫含量等符合国外标准.     

酯交换法制备生物柴油研究进展

综述了酯交换法制备生物柴油的国内外重要研究进展,总结了超临界体系、生物酶催化体系、均相催化体系和非均相催化体系制备生物柴油的研究成果,重点讨论了不同催化剂和实验条件对酯交换反应速率和生物柴油产率的影响,分析了不同反应体系存在的一些关键问题,并对酯交换法制备生物柴油的研究方向进行了展望。     

花生油转酯化制备生物柴油工艺条件的研究

研究了花生油在KOH催化作用下通过酯交换反应制备生物柴油的过程.考察了醇油摩尔比、催化剂用量、反应温度、反应时间等操作条件对反应的影响.结果表明最佳酯交换反应条件为醇油摩尔比61、KOH用量1%(质量分数)、反应温度60℃、反应时间20min.同时,通过气相色谱-质谱对生物柴油进行了结构分析,生物柴油主要由C160、C180、C181和C182的脂肪酸甲酯组成,其中亚油酸甲酯含量最高,相对质量分数高达51.485%.     

用棉籽油制备生物柴油

采用棉籽油为原料连续化生产生物柴油,研究了工艺及设备的设计。由棉籽油与甲醇在催化剂NaOH存在下由酯交换反应制得生物柴油。在优化条件下反应50 min,转化率达到99%。生产的生物柴油,各项指标与天然柴油相似。其各项燃烧指标优于或与普通柴油相仿,满足欧洲Ⅱ排放标准。     

KF/Al2O3催化菜籽油与甲醇合成生物柴油的研究

用等体积浸渍法制备了KF/Al2O3催化剂,并将其用于菜籽油与甲醇酯交换合成生物柴油的研究.考察了反应条件、优化了合成工艺,结果表明制得的KF/Al2O3催化剂在适宜的条件下合成生物柴油的产率达96.7%,同时提出了合成反应的机理.     

生物柴油橡胶相容性的研究

将菜籽油用碱催化酯交换法反应生产生物柴油。然后用生物柴油、0号柴油和加1%甘油的生物柴油在不同的实验条件下与3种不同的橡胶测其相容性。得到生物柴油的橡胶相容性比0号柴油差;加了甘油的生物柴油其橡胶相容性变差。     

可膨胀石墨对动物油脂的催化酯交换反应研究

本研究以动物油为原料，可膨胀石墨作催化剂，通过与乙醇的酯交换反应制备了生物柴油。正交试验考察了反应时间、油一醇质量比和催化剂加入量等因素对生物柴油产率的影响。实验确定酯交换反应最佳反应条件为：油醇质量比1：1．5、催化剂用量为油重的20％、反应时间12h、反应温度控制为80℃。极差分析结果表明：反应时间对生物柴油产率的影响最大，其次为催化剂用量及油醇比例。可膨胀石墨的膨胀容积越大，酯交换反应产率越高。加入表面活性剂可以加快反应速度，提高生物柴油产率。加入壬基酚聚氧乙烯醚（OP-4）后，最佳条件下生物柴油产率为0．935g／g。可膨胀石墨可以作为动物油脂与乙醇酯交换反应的催化荆。     

元宝枫油制备生物柴油

以精炼元宝枫油为原料、固体超强酸为催化剂,通过甲醇酯交换反应制备脂肪酸甲酯(生物柴油)。采用气相色谱法测定反应体系中脂肪酸甲酯的含量。应用正交实验法找出精炼元宝枫油酯交换反应的最佳反应条件为:反应温度60℃,醇油物质的量比6∶1,催化剂用量1.0%,反应时间80 min。在此反应条件下原料油转化率可达98.14%。放大实验所得的生物柴油主要质量指标已达到国家0#柴油质量标准。     

新型催化剂制备生物柴油的动力学

工业生产中常采用碱催化酯交换法制备生物柴油,但原料油中的游离脂肪酸和水分往往会导致产生较多的皂化物,影响生物柴油和甘油的分离,降低了生物柴油的产率。开发的新型生物柴油催化剂SXL较好地解决了上述问题。以精制菜籽油和甲醇为原料,采用液相色谱法跟踪分析生物柴油(脂肪酸甲酯)的质量分数,考察新型催化剂SXL作用下的酯交换反应动力学,并研究该酯交换反应的影响因素,得到相关动力学参数。研究结果表明:在40—60℃,反应速率随反应温度升高而增大;催化剂与菜籽油质量比为2.2%时反应速率较快,产率较高;醇油摩尔比为16∶1时,在较短时间内可达到较高产率;通过假设求证得到催化剂SXL作用下的酯交换反应整个过程是从二级反应向零级反应转变,反应的平均活化能为35.33 kJ/mol,频率因子k0为4.73×105 L/(mol.min)。     

Optimization of biodiesel production process in a continuous microchannel using response surface methodology

We assessed the biodiesel production process in a continuous microchannel through preparation of a heterogeneous catalyst (CaO/MgO) from demineralized water plant sediment. This mixed oxide catalyst was used for transesterification of rapeseed oil as feedstock by methanol to produce biodiesel fuel at various conditions. A microchannel, utilized as a novel reactor, was applied to convert rapeseed oil into biodiesel in multiple steps. The effects of the process variables, such as catalyst concentration, methanol to oil volume ratio, n-hexane to oil volume ratio, and reaction temperature on the purity of biodiesel, were carefully investigated. Box-Behnken experimental design was employed to obtain the maximum purity of biodiesel response surface methodology. The optimum condition for the production of biodiesel was the following: catalyst concentration of 7.875 wt%, methanol to oil volume ratio of 1.75: 3, n-hexane to oil volume ratio of 0.575: 1, and reaction temperature of 70 °C.     

Techno-Economic Evaluation of Biodiesel Production from Waste Cooking Oil—A Case Study of Hong Kong

Fossil fuel shortage is a major challenge worldwide. Therefore, research is currently underway to investigate potential renewable energy sources. Biodiesel is one of the major renewable energy sources that can be obtained from oils and fats by transesterification. However, biodiesel obtained from vegetable oils as feedstock is expensive. Thus, an alternative and inexpensive feedstock such as waste cooking oil (WCO) can be used as feedstock for biodiesel production. In this project, techno-economic analyses were performed on the biodiesel production in Hong Kong using WCO as a feedstock. Three different catalysts such as acid, base, and lipase were evaluated for the biodiesel production from WCO. These economic analyses were then compared to determine the most cost-effective method for the biodiesel production. The internal rate of return (IRR) sensitivity analyses on the WCO price and biodiesel price variation are performed. Acid was found to be the most cost-effective catalyst for the biodiesel production; whereas, lipase was the most expensive catalyst for biodiesel production. In the IRR sensitivity analyses, the acid catalyst can also acquire acceptable IRR despite the variation of the WCO and biodiesel prices.     

非均相法催化制备生物柴油的最新研究进展

非均相连续化工艺是生物柴油规模化工业生产的发展方向。多相催化剂的研制和新型工艺过程的开发一直是生物柴油领域的研究热点,也是实现生物柴油绿色、经济、高效生产的关键。分析了酯交换反应可能的反应机理,综述了国内外生物柴油非均相酸碱催化剂的最新研究进展,评述了多种固体酸碱催化剂在生物柴油的制备中优异的催化性能和存在的问题,介绍了多种新型多相生物柴油反应器及反应分离耦合工艺在生物柴油连续化制备中的应用,最后展望了生物柴油未来的发展前景,指出新型固体酸碱双功能催化剂与先进多相连续反应分离耦合工艺的开发将推动生物柴油领域不断发展。     

酯交换法在生物柴油制备中的研究进展

介绍了国内外生物柴油制备方法的研究进展,主要阐述了非均相催化、均相催化、生物催化和超临界催化技术等酯交换法的研究进展。阐明了各种催化法的优缺点,指出了目前酯交换法研究的热点和未来发展的方向。     

Transesterification of soybean oil to biodiesel using SrO as a solid base catalyst

In this study, transesterification of soybean oil to biodiesel using SrO as a solid base catalyst was studied. The reaction mechanism was proposed and the separate effects of reaction temperature, molar ratio of methanol to oil, mass ratio of catalyst to oil and repeated experiments were investigated. The results showed that the yield of biodiesel produced with SrO as a catalyst was in excess of 95% at temperatures below 70 °C within 30 min. SrO had a long catalyst lifetime and could maintain sustained activity even after being repeatedly used for 10 cycles. The results proved that transesterification of soybean oil to biodiesel using SrO as a catalyst is a commercially viable way to decrease the costs of biodiesel production.     

Preparation of KF/CaO nanocatalyst and its application in biodiesel production from Chinese tallow seed oil

KF/CaO nanocatalyst was prepared by using impregnation method and used to convert Chinese tallow seed oil to biodiesel. The effects of different preparation conditions on biodiesel yield were investigated and the structure of the catalyst was characterized. Transmission electron microscopy (TEM) photograph showed that the catalyst had porous structure with the particle size of 30-100 nm. Brunauer-Emmet-Teller (BET) analysis indicated that the catalyst specific surface area was 109 m² g⁻¹ and average pore size was 97 nm. X-ray diffractometer (XRD) analysis demonstrated that the new crystal KCaF₃ was formed in catalyst, which enhanced catalytic ability. Under the optimal conditions, the biodiesel yield was 96.8% in the presence of as-prepared KF/CaO catalyst, showing potential applications of catalyst in biodiesel industry.     

Biodiesel production from waste frying oil in sub- and supercritical methanol on a zeolite Y solid acid catalyst

Waste frying oil (WFO) is a very important feedstock for obtaining biodiesel at low cost and using WFO in transesterification reactions to produce biodiesel helps eliminate local environmental problems. In this study biodiesel was produced from WFO in sub- and super-critical methanol on a zeolite Y solid acid catalyst. The procedure was optimized using a design of experiments by varying the methanol to WFO molar ratio, the reaction temperature, and the amount of catalyst. Typical biodiesel yields varied from 83 to nearly 100% with methyl esters content ranging from 1.41–1.66 mol·L^-1 and typical dynamic viscosities of 22.1-8.2 cP. Gas chromatography was used to determine the molecular composition of the biodiesel. The reaction products contained over 82 wt-% methyl esters, 4.2 wt-% free acids, 13.5 wt-% monoglycerides, and 0.3 wt-% diglycerides. The transesterification of WFO with methanol around its critical temperature combined with a zeolite Y as an acid catalyst is an efficient approach for the production of biodiesel with acceptable yields.     

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%。     

Biodiesel production from soybean oil using modified calcium loaded on rice husk activated carbon as a low-cost basic catalyst

Activated carbon was obtained by hydrothermal process using rice husk as raw materials. The study in our lab had been developed to produce high-quality biodiesel from soybean oil with the activated carbon-base catalyst. The polyethylene glycol (PEG 400) modified calcium loaded on the rice husk activated carbon (CaO/AC) catalyst was prepared via the dipping method and then was used as a heterogeneous solid-base catalyst to produce biodiesel. The effects of CaO/AC ratio and calcination time on catalytic performance were researched according to the yield of biodiesel, and the optimum reaction conditions for biodiesel from soybean oil via PEG 400–modified CaO/AC catalyst were evaluated. The results showed that the yield of fatty acid methyl ester (FAME) achieved 93.01% at the reaction temperature of 342 K, methanol/oil molar ratio of 10:1, and reaction time of 6 h. All in all, modified CaO/AC catalyst showed very high activity for transesterification of soybean oil and had catalytic repeated availability.