Ultrasound-assisted Biodiesel Production from Waste Cooking Oil at Room Temperature

Waste cooking oil(WCO) is considered to be a promising alternative for vegetable oils that have been traditionally used for biodiesel production. In this study, WCO with a fairly high free fatty acid content was transesterified into biodiesel in a one-step procedureat room temperature(25℃) under ultrasound irradiation and in the presence of potassium hydroxide(KOH) as catalysts. Response surface methodology(RSM) was used to investigate the effects of the methanol/oil molar ratio, reaction time,and catalyst loading on the fatty acid methyl ester(FAME) yield and the biodiesel yield. The optimal reaction conditions for the production of WCO biodiesel were found to be a methanol/oil molar ratio of 8.6:1, a reaction time of 25 min, and a catalyst loading of 2.43 wt%. Under these optimal settings,the FAME and biodiesel yields were 96.4% and 92.7%, respectively. The properties of the resultant WCO biodiesel, including kinetic viscosity, acid number, water content, and flash point, were measured according to ASTM D6751 standards. The obtained results provide useful information for the large-scale production of WCO biodiesel.

Ultrasonic-Assisted Production of Biodiesel from Waste Frying Oil Using a Two-Step Catalyzing Process

This study proposed using waste frying oil rather than refined vegetable oil as an effective way to reduce the raw material cost of producing biodiesel. In addition, the ultrasonic-assisted two-step catalyzing Process was first adopted for the production of biodiesel from waste frying oil. The results show that the total reaction time was less than 50 min and the conversion rate of fatty acid methyl esters (FAMEs) achieved was 97.1%. Therefore, the ultrasonic-assisted two-step catalyzing process has a potential application in producing biodiesel from waste frying oil.

Combined Effect of a Catalytic Reduction Device with Waste Frying Oil-Based Biodiesel on NOx Emissions of Diesel Engines

Internal combustion engines with application in automobiles and other relevant industries constitute significant environmental pollution via the release of toxic exhaust gasses like carbon monoxide (CO), hydrocarbons (HC), particulate matter (PM), and nitrogen oxide (NOx). Engine researchers and manufacturers are challenged to develop external and internal measures to ensure environmentally friendly solutions to accommodate and conform to the growing list of emission standards. Therefore, this work presents an experimental investigation of the NOx emission profile of a diesel engine that is fuelled and fitted with waste frying oil-based biodiesel and catalytic converter. Using a single-cylinder, four-stroke air-cooled CI engine at a constant speed of 1900 rpm and different loadings of 25%, 50%, 75%, and 100%;fitted with a catalytic converter at the exhaust outlet of the engine and linked to a dynamometer and a gas analyser, an experiment was conducted at biodiesel/diesel volume blends of B0 (0/10), B5 (5/95), B20 (20/80), B30 (30/70), B70 (70/30), B100 (100/0);and 30% concentration (v/v), 0.5 litre/hr flow rate of aqueous urea from the catalytic converter. The results show an increasing NOx emission as the biodiesel component increased in the blend. The catalytic converter showed a downward NOx reduction with a significant 68% reduction in efficiency at high exhaust gas temperatures. It is concluded that the combined utilisation of waste frying oil-based biodiesel and the catalytic converter yields substantial NOx emission reduction.

Production Optimization of Biodiesel from Frying Oil Waste to Reduce the Environmental Impacts

The objective of this study was to reduce the environmental impacts of used frying oil waste through the production of biodiesel. A 22 factorial planning has been used to evaluate the influences of alcohol/oil and reaction time on the biodiesel production yield. The optimal condition to produce the biodiesel has been found by use of the response surface methodology and analysis of variance to obtain the fitting model. This study was conducted in Campinas city, Brazil, where were collected the waste oil. An analysis of ecological cost also has been developed. Cooking oils collected from Campinas homes were mixed with ethanol in planned proportions （1：9, 1：7 and 1：5） and were transesterified at 60 ℃ and planned reaction times （30, 60 or 90 min）, in order to obtain biodiesel, using 0.1% NaOH as a catalyst. The results of the physical-chemical analyses demonstrated that the biodiesels obtained possessed characteristics close to those required by Brazilian standards. This fuel could be used in fleets of buses, trucks and machines, or even sold to fuel distributors, which results in a solving between US$0.8 and US$4.5 millions. Thus, Campinas would gain environmental credits and become a sustainable city.

Waste Frying Oils-Based Biodiesel: Process and Fuel Properties

The conversion of waste frying oil into a valuable methyl ester (biodiesel) has been successfully conducted and also the acid pre-treatment process was carried out prior to the main biodiesel production process for lowering waste frying oil free fatty acid (FFA) content below 1%. The physicochemical properties of biodiesel were analyzed to ensure the product could meet the standards of fuel properties. The methanolysis was selected as the biodiesel production technique under various mixing speeds namely 350, 400 and 450 rpm, while the other parameters are maintained at the optimum process conditions such as methanol to oil molar ratio is 6:1, percentage of catalyst loading is 1.0% wt, reaction temperature is 60℃, and reaction time is 50 min. Also, the investigation on the kinematic viscosity, density and flash point of biodiesel was performed against a number of rpm. The standards of ASTM D 6751 were applied to measure the entire prescribed properties of biodiesel. The highest yield of biodiesel obtained was 99%. The values of flash point, kinematic viscosity and density were in the range of specified limitations. Other biodiesel properties fulfilled the diesel engine application requirements.

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 1.41-1.66mol.L-~ and typical dynamic viscosities of 22.1-8.2 cE 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-% monoglycer- ides, 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.

Flow-mode synthesis of biodiesel under simultaneous microwave–magnetic irradiation

In this study,aiming at optimization of a novel continuous biodiesel production system was developed by combining technologies based on microwaves and magnetic fields.Factors affecting microwave-assisted biodiesel(alkyl esters)production reaction were analyzed in this investigation.Studied factors included magnetic field intensity(0,0.225 and 0.450 T),microwave power(400,821,and 1181 W),percentages of KOH and Na OH catalysts at constant concentrations of 1 wt%(0,50%and 100%),and percentages of ethanol and methanol at a constant molar ratio of 6:1(0,50%and 100%).Response Surface Methodology(RSM)was used to optimize the reaction conditions.RSM-based analysis indicated that,all independent parameters had significant effects on the reaction efficiency.Results of the investigations reveal that the largest effects on the conversion efficiency were due to type of alcohol and magnetic field intensity.The optimized conditions were found to be a magnetic field intensity of 0.331 T,a microwave power of 677.77 W,catalyst percentages of 30.35%and 69.65%for KOH and Na OH,respectively,and alcohol percentages of 80.47%and 19.53%for methanol and ethanol,respectively.Under the optimal conditions,yield of the reaction was 96.2%.

Biodiesel Production from Waste Cooking Oil Using Sulfuric Acid and Microwave Irradiation Processes

A comparative study of biodiesel production from waste cooking oil using sulfuric acid (Two-step) and microwave-assisted transesterification (One-step) was carried out. A two-step transesterification process was used to produce biodiesel (alkyl ester) from high free fatty acid (FFA) waste cooking oil. Microwave-assisted catalytic transesterification using BaO and KOH was evaluated for the efficacy of microwave irradiation in biodiesel production from waste cooking oil. On the basis of energy consumptions for waste cooking oil (WCO) transesterification by both conventional heating and microwave-heating methods evaluated in this study, it was estimated that the microwave-heating method consumes less than 10% of the energy to achieve the same yield as the conventional heating method for given experimental conditions. The thermal stability of waste cooking oil and biodiesel was assessed by thermogravimetric analysis (TGA). The analysis of different oil properties, fuel properties and process parametric evaluative studies of waste cooking oil are presented in detail. The fuel properties of biodiesel produced were compared with American Society for Testing and Materials (ASTM) standards for biodiesel and regular diesel.

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, Nz adsorption-desorption, simultaneous thermogravimetric analyse/differential scanning calorimetry （TGA/DSC） experiments on the thermal decomposition of kaolinite and Fourier-transform infrared spectrometer （FTIR） analysis. Parameters related to the transesterificaion 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℃; 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.

Biodiesel Production from Waste Cooking Oil by Enzymatic Catalysis Process

Biodiesel is an excellent option for reducing dependence on fossil fuels with environmental advantages by reducing hazardous emissions. The enzymatic transesterification has attracted the attention of researchers in the last decade and the advantages of enzymatic catalysis show that the production of biodiesel by this route has good potential, mainly because it is friendly environment. For biodiesel, production process by enzyme catalysis is chosen the response surface methodology. It is an experimental strategy to find the best operating conditions oftransesterification reaction to improve the biodiesel quality. The Process has three variables： temperature, molar ratio oil-alcohol and catalyst quantity. The process was monitored by GC-FID （gas chromatography with flame ionization detector）. The yield of the transesterification reaction by enzymatic catalysis decreases with increasing temperature, and may be due to inactivation of the enzyme by denaturation at temperatures above 50 ℃. The second-order design used was the ＂CDC （central design composition）＂ which produced a maximum yield of 95.5% in the transesterification reaction by enzymatic catalysis obtained at a temperature of 45 ℃, molar ratio methanol：oil of 8：1 and a catalyst loading of 8% wt.

Biodiesel Production from Waste Cooking Oil over Mesoporous SO42-/Zr-SBA-15

Biodiesel production from waste cooking oils over SO42-/Zr-SBA-15 catalyst was successfully carried out and investigated. SO42-/Zr-SBA-15 catalyst was prepared by one-step process using anhydrous zirconium nitrate as zirconium resource, and endowed with the strong Lewis acid sites formed by supporting the zirconium species onto the SBA-15 surface. The asprepared SOt2-/Zr-SBA-15 showed excellent triglyceride conversion efficiency of 92.3% and fatty acid methyl esters （FAME） yield of 91.7% for the transesterification of waste cooking oil with methanol under the optimized reaction conditions： the methanol/oil molar ratio of 30, the reaction temperature of 160 ℃, the reaction time of 12 h and 10wt% of catalyst. It was noticed that the as-prepared SOa2-/Zr-SBA-15 materials with the higher area surface of mesoporous framework and the surface acidity displayed excellent stability and reusability, maintaining high FAME yield of （74±1）% after seven runs of reaction.

Biodiesel from fish waste oil: synthesis via supercritical methanol and thermodynamic optimization

This study evaluates the potential of local fish waste oil as a feedstock for biodiesel via supercritical methanol transesterification(SCMT).Hexane was used as a cosolvent and the transesterification reaction was carried out in a continuous reactor under supercritical conditions.The response surface methodology(RSM)method was applied to analyse the effect of four independent variables,including the weight ratio of methanol to fish-waste oil(W),the reaction temperature(T),the pressure(P)and the feed flow rate(F),on the yield of the biodiesel production in supercritical methanol.According to the calculated optimal operating condition for the RSM,the values of W(22.3 weight ratio of methanol to fish waste oil),T(270°C),P(112.7 bar)and F(2.0 mL min-1)were achieved.Under the optimum conditions,the highest yield was estimated to be 94.6%(g/g).The obtained yield was found to be close to the theoretical yield(95.2%).This value suggests that the proposed strategy has a promising potential in the production of biodiesel fuel.

Al_(2)O_(3)-GO-SO_(3)H非均相催化剂催化餐厨废油制生物柴油的研究

本文采用共沉淀法,利用氧化铝修饰磺化氧化石墨烯制备了一种非均相催化剂(Al_(2)O_(3)-GO-SO_(3)H),并用扫描电镜(SEM)、X射线光电子能谱(XPS)、X射线衍射(XRD)和傅里叶变换红外光谱(FTIR)对Al_(2)O_(3)-GO-SO_(3)H的理化性质进行表征。研究了Al_(2)O_(3)-GO-SO_(3)H的Al_(2)O_(3):GO质量比、催化温度、醇油摩尔比、催化剂投加量及催化时间对餐厨废油制生物柴油反应的影响。结果表明:以Al_(2)O_(3)-GO-SO_(3)H催化餐厨废油制生物柴油反应中具有较好的催化活性,且生物柴油产率随着Al_(2)O_(3):GO质量比的降低而升高,随催化剂投加量的增大而升高,在反应温度为60℃、醇油摩尔比9:1、催化剂投加量3%(Al_(2)O_(3)与GO质量比1:3)、反应时间5 h时,生物柴油产率达91.23%,催化剂重复用5次后仍有较高生物柴油产率。实验制生物柴油的性能指标达到了《柴油机燃料调和用生物柴油(BD100)》(GB/T 20828—2015)标准。

餐饮业废油脂制取生物柴油的工艺研究

提出了利用餐饮业废油脂生产生物柴油的方法工艺,并且根据碱催化甲醇酯化反应机理提出了甲醇酯化反应的动力学模型,对甲醇酯化制取生物柴油的反应动力学进行了模拟,得到一种与实际工艺非常吻合的模型。

废弃油脂原料SRCA生物柴油技术的研发与工业应用示范

针对废弃油脂品质差,酸值高,难于采用传统的碱催化酯交换技术加工生产生物柴油,中国石化石油化工科学研究院开展了超/近临界甲醇介质中油脂溶解和反应的基础研究,相继解决了甲醇与油脂的互溶、降低反应条件,三脂肪酸甘油酯和游离脂肪酸的深度转化,以及产品质量等问题,成功开发了近临界醇解生物柴油技术(以下简称SRCA),于2009年建成了6万吨/年工业化示范装置,以酸化油和餐厨废油为原料,生产连续稳定,产品收率高且满足国家生物柴油质量标准(GB/T20828-2007).

两步法催化潲水油制备生物柴油的研究

采用两步法催化高酸值潲水油制备生物柴油,第一步先用硫酸铁催化潲水油中游离脂肪酸和甲醇酯化生成脂肪酸甲酯(生物柴油),然后再用氢氧化钾催化潲水油中的甘油三酯和甲醇进行酯交换。结果表明,硫酸铁对酯化反应具有很强的催化活性,而且可以回收利用。通过正交试验得到最佳酯化反应参数:硫酸铁用量2%,反应温度95℃,醇油摩尔比10∶1,反应时间4 h,该条件下游离脂肪酸酯化率达97.22%。酯交换条件为:KOH用量1%,反应温度65℃,反应时间1 h,醇油摩尔比6∶1。经过两步催化,产品中总的脂肪酸甲酯(生物柴油)含量达97.02%。该两步催化法具有不产生酸化废水,不需要耐强酸设备,反应时间短,转化率高,同时硫酸铁可以回收重复利用等优点。

无溶剂系统中固定化脂肪酶催化废油脂转酯生产生物柴油

探讨了无溶剂系统中固定化脂肪酶Novozym 4 35催化餐饮业废油脂转酯生产生物柴油 .反应副产物甘油可吸附在固定化酶载体表面 ,采用丙酮洗涤除去甘油可提高酶的稳定性 .适宜的醇 /油摩尔比、酶用量、反应温度和摇床转速分别为 1,6 6U/g ,35～ 4 0℃和 15 0r/min ,不宜加水到反应体系中 .采用分步加入甲醇的方式可减轻甲醇对酶的毒害作用 .分别在反应进行到 6和 14h时用丙酮除去酶表面的甘油 ,然后按醇 /油摩尔比为 1的比例加入甲醇继续反应 ,反应 30h后产物中的脂肪酸甲酯含量为 88 6 % .连续反应 30 0h后 ,酶活性基本没有下降 .

超声波作用下甲醇钠催化废煎炸油合成生物柴油的研究

采用超声酯化技术进行生物柴油的合成，在超声波频率28kHz，屏级电流0．6A，甲醇钠加量0．5％，醇油比9：1（摩尔比），超声波作用时间40min时，酯化产率可达95％以上。与传统合成方法相比，该方法可缩短反应时间30～50min，催化剂加量也比传统方法低1～2倍。

BrФnsted酸离子液体催化废油脂制备生物柴油

采用磺酸类BrФnsted酸离子液体作为催化剂,研究了不同工艺条件下催化废油脂制备生物柴油的过程.以地沟油为原料,醇/油摩尔比12:1,催化剂用量为油质量的2%,在140℃下反应5h,产物中脂肪酸甲酯的含量达到86.8%.在同样的反应条件下,催化剂重复使用9次后其活性无明显变化.该催化剂对废油脂制备生物柴油具有较高的催化活性和良好的重复使用性能.

超声波辅助下脂肪酶催化高酸值废油脂制备生物柴油

探讨了超声波辅助条件下脂肪酶催化高酸值废油脂转化为生物柴油的反应。来源于Aspergillus oryzae和Candida antarctica的固定化脂肪酶，在超声波辅助下，对高酸值废油脂转化为生物柴油具有高的催化活性。以来自于C．antarctica的固定化脂肪酶Novozym435为催化剂，以酸价为157mgKOH／g的高酸值废油脂为原料在超声波辅助下与丙醇反应，在脂肪酶用量为油质量的8％、初始醇油摩尔比为3：1、反应温度控制在40～45℃、超声波频率和功率分别采用28kHz和100W的条件下，反应50min转化率达到94．86％。在此条件下，不同碳原子数（C1～C5）的直链和支链醇均有较高的转化率，在短链醇的选择上具有宽广的适应性。超声波还减少了反应产物和反应体系中其他黏性杂质在固定化脂肪酶表面的吸附，回收的Novozym435相较单纯机械搅拌条件下回收的外观干净、分散良好无结块现象、易于洗涤和再次利用，具有良好的操作稳定性。