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%。     

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%。     

白云石非均相催化合成生物柴油的工艺研究

以大豆油、甲醇为原料,研究了通过白云石催化酯交换反应制取生物柴油的工艺的条件。用气相色谱-质谱分析法,并对反应温度、醇油摩尔比、反应时间、催化剂的用量及催化剂粒径进行考察,得出最佳合成条件为:反应温度65℃、反应时间2h、醇油摩尔比7:1,催化剂用量2%,催化剂粒径为80～150目,在此条件下得到生物柴油转化率为77.36%。     

采用抽油烟机废油合成增塑剂的实验研究

以抽油烟机废油脂和正丁醇为原料,甲醇钠为催化剂,通过酯交换反应制取非芳基绿色增塑剂——脂肪酸丁酯。研究了醇酸摩尔配比、催化剂用量、反应时间和反应温度对酯交换反应产物收率的影响。结果表明,该反应的最佳工艺条件为:醇油摩尔比为4∶1,催化剂用量为0.5%,反应时间为4 h,反应温度110℃。在最佳工艺条件下,酯交换反应产物丁酯增塑剂收率达到了83.05%以上。利用气相色谱对产物含量进行了分析,用红外光谱表征了产物的结构。     

碱催化法制备生物柴油工艺研究

在250m l间歇式高压反应器中,以大豆油为原料,研究KOH催化甲醇酯交换反应制备生物柴油的工艺条件。主要考察了醇油摩尔比、反应温度、反应时间、催化剂用量等操作条件对脂肪酸甲酯转化率的影响。结果表明,当KOH用量为1%(wt),醇油摩尔比为5∶1,反应温度为65℃时,反应时间为15m in,脂肪酸甲酯的转化率可以达到92%。     

分子筛型固体碱催化剂用于酯交换反应制备生物柴油

采用等体积浸渍法制备了NaOH/NaX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NaOH负载量、焙烧温度、反应时间、反应温度、催化剂用量和醇油摩尔比对转化率的影响。结果表明,在NaOH负载量25%,焙烧温度500℃,反应时间4 h,反应温度65℃,催化剂用量3%和醇油摩尔比12条件下,转化率达95.3%。     

脂肪酸乙酯合成工艺研究

研究了大豆油和乙醇进行酯交换反应合成脂肪酸乙酯的工艺。考察了催化剂类型、催化剂用量、n(醇)∶n(油)、反应温度以及反应时间对酯交换率的影响,结果表明最佳合成工艺条件为反应温度60℃,n(醇)∶n(油)=5∶1,w(NaOMe)=1.0%,反应时间4h,在此条件下,酯交换率可达到96.7%。     

固体超强酸Zr(SO4)2/TiO2催化合成生物柴油

以固体超强酸Zr(SO4)2/TiO2为催化剂,通过酯交换反应催化工业用棕榈油与甲醇合成了生物柴油,讨论了醇油摩尔比、催化剂用量、反应时间对棕榈油转化率的影响,确定了较佳工艺条件:醇油摩尔比5∶1,催化剂用量为棕榈油质量的8.8%,在78℃~81℃微沸下反应5 h。此时棕榈油的转化率可达89.3%,在此优化条件下进行第二步反应可使转化率达到98.6%。采用GC-MS对产物进行了分析,鉴定为脂肪酸甲酯。     

Na^＋／MgO固体碱催化制备生物柴油

利用等体积浸渍法制备了不同浓度NaOH浸渍的Na+/MgO固体碱,并考察了它们对制备生物柴油的催化性能.探讨了催化剂用量,醇油摩尔比,反应温度及反应时间对酯交换反应的影响,利用正交分析得到了反应的最佳条件:催化剂用量为原料油质量的2%,醇油摩尔比12:1,反应温度为60℃,反应时间90 min,转化率可达82.3%.     

“地沟油”脂肪酶NOVO435生物催化制备生物润滑油的工艺参数

为研究以采用脂肪酶NOVO435催化剂催化制备生物润滑油的相关技术,以地沟油为对象,选用脂肪酶NOVO435为催化剂,通过正交试验,对该催化剂在地沟油制备生物润滑油的工艺参数上进行探讨.研究结果表明,催化剂制备生物润滑油的最优工艺条件为：油醇摩尔比1∶6、催化剂用量为油质量的1％、反应温度65℃,反应时间21h;酯交换反应转化率最高可达92.93％.该生物润滑油的成分是由9-十八碳烯酸丁酯、十六酸丁酯、十八酸丁酯、9-二十碳烯酸丁酯等组成.其中脂肪酸丁酯中的9-十八碳烯酸丁酯含量最高,相对质量分数高达48.3％.     

固体催化剂催化高酸值鱼油的甲酯化研究

以高酸值鱼油为原料,利用Amberlyst15固体酸催化剂在温和条件下进行酯化反应降低酸值,再由氧化钙固体碱催化剂催化转酯化得到鱼油脂肪酸甲酯。采用正交设计优化反应条件,预酯化：催化剂用量15%,反应温度75℃,n（醇）/n（油）14,反应时间1.5 h,酸值降为3.35 mg/g,二次预酯化酸值降至1.24 mg/g;酯交换：催化剂用量为10%,反应温度65℃,n（醇）/n（油）为6,反应时间为3 h,鱼油甲酯收率为93.7%。     

Conversion of waste cooking oil to biodiesel using ferric sulfate and supercritical methanol processes

In this comparative study, conversion of waste cooking oil to methyl esters was carried out using the ferric sulfate and the supercritical methanol processes. A two-step transesterification process was used to remove the high free fatty acid contents in the waste cooking oil (WCO). This process resulted in a feedstock to biodiesel conversion yield of about 85-96% using a ferric sulfate catalyst. In the supercritical methanol transesterification method, the yield of biodiesel was about 50-65% in only 15 min of reaction time. The test results revealed that supercritical process method is probably a promising alternative method to the traditional two-step transesterification process using a ferric sulfate catalyst for waste cooking oil conversion. The important variables affecting the methyl ester yield during the transesterification reaction are the molar ratio of alcohol to oil, the catalyst amount and the reaction temperature. The analysis of oil properties, fuel properties and process parameter optimization for the waste cooking oil conversion are also presented.     

酯旨交换法合成椰子油甲酯

以椰子油为原料利用酯交换法制备了脂肪酸甲酯.分析测定了椰子油的平均(相对)分子质量,考察了反应条件对反应的影响.结果表明,优化的反应条件为:NaOH用量为1%(质量分数),醉油比为6:1(物质的量比),反应温度70 ℃,反应时间120 min,此条件下脂肪酸甲酯转化率达96%以上,椰子油平均相对分子质量为664.25.     

Biodiesel production from soybean oil using calcined Li–Al layered double hydroxide catalysts

The transesterification of soybean oil to fatty acid methyl esters was studied using a calcined Li–Al layered double hydroxide catalyst. The catalyst exhibited high activity, with near quantitative oil conversion being obtained under mild conditions (reflux temperature of methanol) and short reaction times (≤ 4 h). The influence of relevant parameters (catalyst calcination temperature, methanol to oil mole ratio, catalyst charge and reaction duration) was examined.     

Biodiesel production from waste cooking palm oil using calcium oxide supported on activated carbon as catalyst in a fixed bed reactor

A reactor has been developed to produce high quality fatty acid methyl esters (FAME) from waste cooking palm oil (WCO). Continuous transesterification of free fatty acids (FFA) from acidified oil with methanol was carried out using a calcium oxide supported on activated carbon (CaO/AC) as a heterogeneous solid-base catalyst. CaO/AC was prepared according to the conventional incipient-wetness impregnation of aqueous solutions of calcium nitrate (Ca(NO₃)₂·4H₂O) precursors on an activated carbon support from palm shell in a fixed bed reactor with an external diameter of 60 mm and a height of 345 mm. Methanol/oil molar ratio, feed flow rate, catalyst bed height and reaction temperature were evaluated to obtain optimum reaction conditions. The results showed that the FFA conversion increased with increases in alcohol/oil molar ratio, catalyst bed height and temperature, whereas decreased with flow rate and initial water content in feedstock increase. The yield of FAME achieved 94% at the reaction temperature 60 °C, methanol/oil molar ratio of 25: 1 and residence time of 8 h. The physical and chemical properties of the produced methyl ester were determined and compared with the standard specifications. The characteristics of the product under the optimum condition were within the ASTM standard. High quality waste cooking palm oil methyl ester was produced by combination of heterogeneous alkali transesterification and separation processes in a fixed bed reactor. In sum, activated carbon shows potential for transesterification of FFA.     

Production of mixed methyl/ethyl esters from waste fish oil through transesterification with mixed methanol/ethanol system

Biodiesel (mixed fatty acid methyl/ethyl esters) was prepared from waste fish oil through base-catalyzed transesterification with mixed methanol/ethanol system. Effect of methanol/ethanol (% v/v), type and concentration of the catalyst, mixed alcohols to oil molar ratio, the reaction temperature, and the reaction time on the biodiesel yield was optimized. Maximum biodiesel yield (97.30?wt%) was produced by implementing 1:1 methanol/ethanol (v/v), 1.0?wt% KOH, 6:1 mixed alcohols to oil molar ratio, 40°C reaction temperature, and 30?min of reaction time. Conversion of the waste fish oil to mixed methyl/ethyl esters was confirmed by ¹H NMR spectroscopy. Fuel properties of the resulting biodiesel in addition to its blends with petrodiesel were in good agreement with specifications of ASTM D6751 and ASTM D7467, respectively. Therefore, it was concluded that using mixed alcohol system for biodiesel production could reduce the production cost through reducing conditions required for maximum conversion.     

Biodiesel synthesis via homogeneous Lewis acid-catalyzed transesterification

Lewis acids (AlCl₃ or ZnCl₂) were used to catalyze the transesterification of canola oil with methanol in the presence of terahydrofuran (THF) as co-solvent. The conversion of canola oil into fatty acid methyl esters was monitored by ¹H NMR. NMR analysis demonstrated that AlCl₃ catalyzes both the esterification of long chain fatty acid and the transesterification of vegetable oil with methanol suggesting that the catalyst is suitable for the preparation of biodiesel from vegetable oil containing high amounts of free fatty acids. Optimization by statistical analysis showed that the conversion of triglycerides into fatty acid methyl esters using AlCl₃ as catalyst was affected by reaction time, methanol to oil molar ratio, temperature and the presence of THF as co-solvent. The optimum conditions with AlCl₃ that achieved 98% conversion were 24:1 molar ratio at 110 °C and 18 h reaction time with THF as co-solvent. The presence of THF minimized the mass transfer problem normally encountered in heterogeneous systems. ZnCl₂ was far less effective as a catalyst compared to AlCl₃, which was attributed to its lesser acidity. Nevertheless, statistical analysis showed that the conversion with the use of ZnCl₂ differs only with reaction time but not with molar ratio.