以废食用油为原料的生物柴油研制

介绍了废食用油脂在KF/CaO催化剂作用下,与乙醇通过酯交换反应,生产生物柴油的研究。通过研究废食用油的预处理,反应时间,反应温度,原料与催化剂配比及催化剂用量等操作条件对反应的影响,摸索反应的最佳操作条件。实验结果表明,KF/CaO催化剂,在活性白土为载体,在KF与CaO质量比为1/3时,温度为800℃,烧制4 h时得到的催化剂活性最好。该反应得最适宜的操作条件是：醇油体积比为6∶1,催化剂量KF/CaO为原料油质量的2%,反应温度为70℃,反应时间为60min。     

Investigation on Particulate Oxidation from a DI Diesel Engine Fueled with Three Fuels

In this study, particles generated from a direct-injection (DI) diesel engine fueled with biodiesel, ultra-low-sulfur diesel (ULSD, <10 ppm-wt), and low-sulfur diesel (LSD, <500 ppm-wt) were investigated experimentally for their oxidation properties, using the thermogravimetric analysis (TGA), at five engine loads. Kinetic analysis of particulate oxidation was conducted based on the mass loss curves obtained from the TGA. The activation energy was found to be in the range of 142–175, 76–127, and 133–162 kJ/mol for the particulate samples for ULSD, biodiesel, and LSD, respectively. The particulate oxidation rate decreases with the increase of engine load for each fuel, and at each engine load, the oxidation rate decreases in the order of biodiesel, LSD, and ULSD. The primary particle size, nanostructure, and volatile fraction were also investigated for different particulate samples. The results indicate that the higher oxidation rate of biodiesel particles could be related to the smaller primary particle size, the more disordered nanostructure, and the larger volatile fraction, compared with the ULSD and LSD particles. The increase of sulfur content in a diesel fuel has a limited influence on primary particle size and nanostructure, while inducing a larger volatile fraction, which might be one of the reasons for the stronger oxidative reactivity of the LSD particles, compared with the ULSD particles.

Copyright 2012 American Association for Aerosol Research     

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%。     

餐饮废油制生物柴油研究进展

简述了餐饮废油（ WCO）转化为生物柴油的反应原理,比较了利用WCO转化制备生物柴油的各种方法,主要有均相转化法（包括酸催化法、碱催化法和酸碱两步催化法）、非均相转化法（包括固体碱催化法、固体酸催化法）、酶催化法、超临界转化法等,分析了不同方法的特点。     

地沟油酶法制生物柴油的GC-MS测定

地沟油制的生物柴油成分复杂,通过气相色谱-质谱法测定脂肪酸甲酯、游离脂肪酸的峰形和相对位置,由此可确定各成分的含量,并准确计算出生物柴油的转化率和产率.     

脂肪酶催化食用废油制备生物柴油

利用脂肪酶为催化剂,食用废油与甲醇反应,制备生物柴油,最佳酯化反应条件为反应温度50℃、脂肪酶催化剂用量为原料量的3%、甲醇与食用废油体积比为3∶1、共溶剂丁酮量为甲醇量的1/6、pH=7,反应时间4h,生物柴油产率可达到78%,对产品的各项指标测定,均达到GB/T20828-2007要求,指标并与0#石化柴油相接近。     

利用废食用油制备生物柴油的研究

对利用废食用油制备生物柴油的预酯化-酯交换工艺进行了研究。结果表明,预酯化的最佳工艺条件为：乙醇用量为80 mL、催化剂浓硫酸用量为1 g、反应时间为3 h、反应温度为70℃;酯交换的最佳工艺条件为：乙醇用量为60 mL、催化剂氢氧化钾用量1 g、反应时间为40 min、反应温度为70℃。在此条件下可使50 mL废食用油的酸值由40.27 mg KOH/g降到1.52 mg KOH/g,粗生物柴油的产率可达93.71%。     

酶催化餐饮业废油脂生产生物柴油的研究

研究了利用餐饮业废油脂和甲醇,在无溶剂系统中通过脂肪酶的转酯作用来生产生物柴油.结果表明,醇油摩尔比为3∶1时甲醇转化率只能达到48%左右,醇油摩尔比低于1∶1时甲醇转化率能达到95%以上,采用分批添加法,甲醇总转化率可以明显提高到80%以上.反应体系的最适初始水活度应控制在0.54～0.75之间,随着反应温度的升高,酯交换反应的速度加快,但酶失活率也随之增大.     

地沟油生物柴油流变学特性研究

生物柴油是一种可以替代矿物柴油使用的环保燃油和可再生能源,粘度是评价生物柴油流动性能的一个重要指标。文章对地沟油生物柴油和0#柴油混合的流变学特性进行研究,并确定了地沟油生物柴油的流体类型为牛顿流体,在剪切力作用下能保持很好的稳定性,其粘度不随搅拌时间的变化而变化,随浓度的增大而增加,温度的升高而降低。     

非均相催化剂两步法催化潲水油制备生物柴油

对取自餐饮的潲水油进行一系列预处理,脱去其中的胶类、色素、水分等杂质,然后用自制的固体酸、固体碱催化剂经"两步法"工艺将其转化为生物柴油。结果发现,在预酯化反应中,催化剂A用量为6%、醇油摩尔比为12∶1,反应2.5 h后,潲水油的酸值由50 mg KOH.g-1降至2 mg KOH.g-1。通过正交实验得到碱催化酯交换反应最佳条件为:反应时间2 h、反应温度100℃、催化剂B用量6%、醇油摩尔比9∶1,在此条件下转化率达96.4%。表明所制备的固体酸、固体碱催化剂能有效将潲水油转化为生物柴油。     

Optimized Production of Biodiesel from Waste Cooking Oil by Lipase Immobilized on Magnetic Nanoparticles

Biodiesel, a non-toxic and biodegradable fuel, has recently become a major source of renewable alternative fuels. Utilization of lipase as a biocatalyst to produce biodiesel has advantages over common alkaline catalysts such as mild reaction conditions, easy product separation, and use of waste cooking oil as raw material. In this study, Pseudomonas cepacia lipase immobilized onto magnetic nanoparticles (MNP) was used for biodiesel production from waste cooking oil. The optimal dosage of lipase-bound MNP was 40% (w/w of oil) and there was little difference between stepwise addition of methanol at 12 h- and 24 h-intervals. Reaction temperature, substrate molar ratio (methanol/oil), and water content (w/w of oil) were optimized using response surface methodology (RSM). The optimal reaction conditions were 44.2 °C, substrate molar ratio of 5.2, and water content of 12.5%. The predicted and experimental molar conversions of fatty acid methyl esters (FAME) were 80% and 79%, respectively.     

碱均相催化制备生物柴油工艺研究

对碱均相催化制备生物柴油工艺进行研究,考察了主要工艺参数醇油比、催化剂浓度、反应温度、反应时间对生物柴油得率的影响.结果表明,在碱催化条件下,工艺参数的最优组合为醇油化30:1、催化剂浓度1.0%、反应温度60℃、反应时间40 min,最高生物柴油得率为89.06%.生物柴油的实测密度、粘度、闪点(闭口)分别为0.875 g·mm-3、4.7cst、133℃.     

餐饮业废油脂生产生物柴油绿色化工艺的研究

提出了一种清洁、环境友好的餐饮业废油脂制备生物柴油的方法和工艺.以磁性固体超强酸SO2-4/TiO2-Fe3O4为非均相催化剂,以餐饮业废油脂为原料与甲醇进行酯交换反应制备生物柴油;利用三因素一次回归正交设计实验方法,考察了反应温度、甲醇用量、催化剂用量对废油脂酯转化率的影响,确定了制备生物柴油的最佳反应条件;通过对实验结果的处理,求出了回归方程;数理统计分析表明回归方程可靠适用;同时利用IR、XRD、SEM、EDS等对磁性固体超强酸SO2-4/TiO2-Fe3O4催化剂的结构进行了表征.与传统的均相催化剂(H2SO4、NaOH) 相比,磁性固体超强酸具有催化活性高、易于分离、可重复使用的特点,是制备生物柴油的环境友好型固体酸催化剂.     

Improving Waste Cooking Oil Quality for Biodiesel Production with the Ethanolic By-product of Soybean Oil Extraction

Waste cooking oils (WCO) can be used as feedstock for biodiesel (fatty acid ethyl or methyl esters—FAEE or FAME) production. Their usual high acidity, high moisture, and low stability can impair the reaction yield and generate a low-quality biodiesel. Here, we performed liquid–liquid washings using WCO and ethanol-based solvents with the goal of generating oil-rich miscella as FAEE feedstocks with a higher quality than WCO. Three different solvents were evaluated: 99% ethanol, 95% ethanol, and the soybean oil extraction ethanolic phase (SEP), a by-product with immense unexplored antioxidant potential obtained by extracting soybean oil using ethanol. Washings were performed in a 1000 mL flat-bottom flask at 78.1 °C, using a 1:2 (w/v) oil/solvent ratio, under magnetic stirring (1200 rpm) for 10 min. Ethyl esters were prepared via homogeneous alkali transesterification using WCO and oil-rich miscella as feedstocks. Treatments reduced the acid value by 40–61% and the peroxide value by 15–50%. Improvements in feedstock quality generated 24–54% higher biodiesel yields. The oil-rich phase produced with SEP was 15% more resistant to oxidation than WCO. This was attributed to the transference of isoflavones from the SEP. However, biodiesel from treated samples presented equal or lower oxidative stability than FAEE from WCO. High-performance liquid chromatography (HPLC) analysis showed that no isoflavones remained in biodiesel after purification. Pretreatment of WCO with ethanol-based extracts such as the SEP has great potential to improve WCO quality for biodiesel production as it can be a source of plant-based antioxidants.     

Use of Phagotrophic Microalga Ochromonas danica to Pretreat Waste Cooking Oil for Biodiesel Production

In this study, the feasibility of pretreatment and/or upgrading of waste cooking oil (WCO) using the microalga Ochromonas danica was investigated. Two WCO samples with initial acid values (AV) of 10.7 mg KOH/g (~5.4 % FFA content) and 3.9 mg KOH/g (~2.0 % FFA content) were examined. The algal cells engulfed oil droplets and grew rapidly on both WCO samples. The cell growth rates on WCO were compared with the rates on olive oil, with or without surfactant addition to make the oil droplets smaller and easier for algal ingestion. Comparison was also made with the growth rate in a sugar‐based medium. More importantly, contacting the WCO with the phagotrophic O. danica cells was found to decrease the acid values of the remaining oil by 2.8 and 2.4 mg KOH/g WCO, respectively. The O. danica‐pretreated WCO, with lower acid values, are potentially better feedstock for biodiesel production.     

地沟油制备生物柴油的研究进展

生物柴油是一种原料广泛的可再生性燃料资源,目前世界各国正掀起开发利用生物柴油资源的热潮,与矿物柴油相比,它具有低含硫和低排放污染,可再生,优良的生物可降解性等特点,有广阔的发展前景,而原料问题是制约生物柴油产业发展的瓶颈。地沟油来源广泛,廉价易得,是制备生物柴油的良好原料。利用地沟油制备生物柴油不但可以缓解能源危机、环境污染等社会问题,还提供了废弃食用油脂的合理化利用方式、防止废弃食用油脂再次返回餐桌。文章综述了地沟油的来源及特点、生物柴油的生产技术和应用现状以及我国生物柴油行业存在的问题,并提出了相应的合理化建议。     

排放影响的研究综述

生物柴油是内燃机用石化柴油的替代燃料之一。本文从4个方面梳理了生物柴油对车用柴油机NO_X排放影响研究的现状,探讨了NO_X排放增加、减少的原因,从改进生物柴油和柴油发动机两大方面细致分析了降低NO_X排放的措施,给出了进一步研究影响NO_X排放的方向。     

生物柴油对车用柴油机NO_X排放影响的研究综述

生物柴油是内燃机用石化柴油的替代燃料之一。本文从4个方面梳理了生物柴油对车用柴油机NOX排放影响研究的现状,探讨了NOX排放增加、减少的原因,从改进生物柴油和柴油发动机两大方面细致分析了降低NOX排放的措施,给出了进一步研究影响NOX排放的方向。     

Mixed Alkyl Esters from Cottonseed Oil: Improved Biodiesel Properties and Blends with Diesel Fuel

Transesterification of refined cottonseed oil (CSO) was carried out with methanol, ethanol, 1-butanol, and various mixtures of these alcohols to produce biodiesel. In the mixed alcohol transesterifications, formation of methyl esters was favored over ethyl and butyl esters. The influence of ester head group on fuel properties was determined. Specifically, cold flow properties, lubricity, and energy content improved in the order: CSO butyl esters (CSBE, best) > ethyl esters (CSEE) > methyl esters (CSME). Higher kinematic viscosities (KVs) as well as lower iodine values (IVs) and wear scars were observed with larger ester head groups. Blends of CSME, CSEE and CSBE exhibited properties intermediate to the neat esters. All ester samples were within the limits prescribed in ASTM D6751 and EN 14214 for cetane number, acid value (AV), glycerol (free and total) content, sulfur, and phosphorous. Also examined was the influence of blending alkyl esters with petrodiesel. All blends exhibited improved cold flow properties versus unblended alkyl esters. Enhanced lubricity was observed after blending. With increasing content of biodiesel, higher KVs and lower energy contents were observed. Finally, all blends were within the limits specified in ASTM D975 and D7467 for AV, KV and sulfur.     

用废油脂制备生物柴油的催化材料的结构与性能研究

用废油脂制备生物柴油时所用的催化剂的结构与性能研究,包括对负载型固体酸催化剂、负载型固体碱催化剂和离子液体催化剂的研究,并对生物柴油催化剂的发展进行了展望。