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1.
以氢化棉油脂肪酸和蔗糖为原料合成了氢化棉油脂肪酸蔗糖酯 ,最佳合成条件为 n(脂肪酸酯 )∶ n(蔗糖 ) =1∶ 1,亲合剂为反应物质量的 3 0 % ,催化剂用量为反应物质量的 2 .1% ,反应温度为 15 5℃ ,反应时间为 6h  相似文献   

2.
梁英 《精细化工中间体》2005,35(1):53-54,57
以固载杂多酸 TiGeW12 O40/TiO2 为多相催化剂,对以葡萄糖、硬脂酸、1,2-丙二醇、十二烷基硫酸钠等为原料合成葡萄糖酯的微乳化反应条件进行了研究。实验表明,TiGeW12O40/TiO2 是合成葡萄糖酯的良好催化剂,优化反应条件是:n(糖)∶n(酸)=1∶1.2 ,催化剂用量为反应物总量的2%,反应时间为1.5 h,葡萄糖硬脂酸酯的收率是92.4%。  相似文献   

3.
TiSiW12O40/TiO2催化合成葡萄糖酯的研究   总被引:56,自引:4,他引:52  
《精细化工》2001,18(7):408-410
以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,对以乙酸酐、丙酸、丁酸、异丁酸和葡萄糖为原料合成葡萄糖酯的反应条件进行了研究.实验表明TiSiW12O40/TiO2是合成葡萄糖酯的良好催化剂,最佳反应条件为n(糖)∶n(酸)=1∶6,催化剂用量为反应物料总质量的2.0%,反应时间为2h.上述条件下,葡萄糖五乙酸酯的产率为88.7%,葡萄糖五丙酸酯的产率为84.5%,葡萄糖五丁酸酯的产率为85.4%,葡萄糖五异丁酸酯的产率为86.4%.  相似文献   

4.
TiSiW_(12)O_(40)/TiO_2催化合成葡萄糖酯的研究   总被引:38,自引:0,他引:38  
杨水金  梁永光 《精细化工》2001,18(7):408-410
以固载杂多酸盐TiSiW12 O4 0 /TiO2 为多相催化剂 ,对以乙酸酐、丙酸、丁酸、异丁酸和葡萄糖为原料合成葡萄糖酯的反应条件进行了研究。实验表明 :TiSiW12 O4 0 /TiO2 是合成葡萄糖酯的良好催化剂 ,最佳反应条件为 :n(糖 )∶n(酸 ) =1∶6 ,催化剂用量为反应物料总质量的 2 0 % ,反应时间为 2h。上述条件下 ,葡萄糖五乙酸酯的产率为 88 7% ,葡萄糖五丙酸酯的产率为 84 5 % ,葡萄糖五丁酸酯的产率为 85 4% ,葡萄糖五异丁酸酯的产率为 86 4%。  相似文献   

5.
羧酸糠醇酯的合成研究   总被引:3,自引:0,他引:3  
以糠醇和酰氯为原料 ,六氢吡啶为催化剂 ,氧化钙为缚酸剂合成了辛酸糠醇酯 ,并考察了反应物的配料比 ,溶剂、缚酸剂、催化剂的用量等因素对辛酸糠醇酯合成反应的影响。经单因素试验确定的最佳反应条件为 :n(糠醇 )∶n(辛酰氯 ) =1 .4∶ 1 .0 ;n(六氢吡啶 )∶n( Ca O)∶ n(辛酰氯 ) =0 .1∶ 1 .6∶ 1 .0 ,溶剂苯的用量为 60 m L(以辛酰氯 0 .1 mol计 ) ,在此条件下合成的辛酸糠醇酯的收率为 91 .5 % ,产品的质量分数为 99%。按该条件还合成了丙酸糠醇酯和异戊酸糠醇酯 ,收率分别为85 .2 %、94.0 % ,产品的质量分数均为 99%以上。  相似文献   

6.
在相转移催化剂存在下,以2,4-二羟基二苯甲酮、丙烯酸(2′-氯乙基)酯为原料合成2-羟基-4-丙烯酰氧乙氧基二苯甲酮,分别研究了反应温度、反应时间、原料配比、催化剂用量、阻聚剂用量等条件对合成反应的影响,确定了最佳工艺条件是:反应温度110℃;反应时间6h;n(2,4-二羟基二苯甲酮)∶n(丙烯酸(2′-氯乙基)酯)∶n(氢氧化钠)=1∶1.15∶1.2;溶剂用量为40mL,催化剂用量为0.8g、阻聚剂用量0.6g(相对于0.1 mol 2,4-二羟基二苯甲酮),产品收率可达到85.71%。  相似文献   

7.
酯交换法合成共轭亚油酸三甘酯   总被引:6,自引:1,他引:6  
采用酯交换反应,以共轭亚油酸乙酯、甘油为原料,脂肪酸钾为均相化试剂,无水K2CO3为催化剂,在压力~1 0kPa下反应制得共轭亚油酸三甘酯。合成工艺条件:n(共轭亚油酸乙酯)∶n(甘油)=6∶1;酯化反应温度140℃;反应时间~1 5h;无水K2CO3用量为共轭亚油酸乙酯质量的0 5%~1%;按统计平均值,产物三甘酯脂肪酸侧链中w(共轭亚油酸)>80%;产率(以甘油计)60%~65%。  相似文献   

8.
以三(二亚苄基丙酮)二钯(Pd2dba3)为催化剂,2-双环己基膦-2',4',6'-三异丙基联苯(Xphos)为配体,采用联硼酸频哪醇酯[B2(pin)2]与对叔丁基氯苯(4-tert-butyl-1-chlorobenzene)反应合成对叔丁基苯基硼酸酯。通过研究Pd催化剂与配体的用量及比例、硼试剂的用量、碱的种类、不同的反应溶剂、温度及时间对反应收率的影响,确定了苯基硼酸酯合成的最佳条件为:n(对叔丁基氯苯)∶n(Pd2dba3)∶n(Xphos)∶n[B2(pin)2]∶n(KOAc)=1∶0.01∶0.04∶2∶3,以乙醇(Et OH)为溶剂于60℃反应1 h,收率达98%。  相似文献   

9.
彭冬梅  张灏  周逸婧  马宁  周丽梅 《江苏化工》2008,36(6):29-31,50
以麦芽糖醇和脂肪酰氯为主要原料合成麦芽糖醇脂肪酸酯。通过对影响反应的催化剂用量、溶剂的用量、反应温度、反应时间、原料配比等主要因素的考察,发现在以麦芽糖醇糖/脂肪酰氯为1∶1.25,催化剂(碳酸钾)用量为麦芽糖醇用量的15%~20%,溶剂(冰醋酸)/麦芽糖醇的用量比为6~7mL/1g,反应温度110℃的条件下,反应10h,麦芽糖醇脂肪酸酯的收率可达93%~95%。  相似文献   

10.
以乙炔(C_2H_2)、CO和正丁醇为原料,采用PdBr_2为主催化剂,在常压、55℃条件下,双羰基化一步合成丁(烯)二酸丁酯。考察了催化剂用量、助剂种类及用量、溶剂种类、反应温度和反应时间对丁(烯)二酸二丁酯收率的影响。结果表明,在Pd Br2用量0.04g,n(PdBr_2)∶n(LiBr)=1∶8,甲基磺酸0.1 mL,30 mL乙腈为溶剂,n(C2H_2)∶n(CO)=1∶2,101 kPa,55℃,反应3 h的反应条件下,丁(烯)二酸二丁酯的收率达到76.11%。  相似文献   

11.
Methyl esters of alkali-isomerized safflower oil fatty acids after elaidinization with sulfur were treated with styrene in the presence of hydroquinone, with or without solvents. A combination of column chromatography and gas liquid chromatography techniques was employed for the estimation of the methyl esters of unreacted fatty acids, Diels-Alder adduct and polymers in the reaction products. Maximum yield of the Diels-Alder adduct (26.6%) was obtained when the elaidinized methyl esters of the fatty acids were treated with 1.5 moles of styrene per mole of linoleic acid in safflower oil fatty acids at 200–210 C for 6 hr. The methyl ester of the adduct was isolated in about 90% purity from the reaction product by vacuum distillation followed by solvent fractionation. The butyl ester of the adduct and the epoxy derivative of the methyl ester adduct were prepared and characterized.  相似文献   

12.
Modification of the fatty acid composition of soy lecithin, principally at its 1-position, was investigated by interchange reaction with the methyl ester of individual fatty acids and a lipase as the catalyst. The consequent effect on the surface activity of soy lecithin was also examined. The interchange reaction was carried out by heating a mixture of soy lecithin and methyl ester of a fatty acid at 60°C for 48 h with 10% (by weight of the reactants) Mucor miehei lipase. The lipase was filtered from the reaction mixture, and the product was isolated by combination of acetone extraction, which removed the methyl ester fraction, and by preparative thin-layer chromatography separation. The soy lecithin showed distinct change in its fatty acid composition in the sn-1 position. Capric acid was incorporated by 8.4%, while lauric acid and myristic acid were introduced at 14.1 and 15.7%, respectively. The linolenic acid percentage was increased by about 10 units. The interfacial tension of soy lecithin changed significantly after incorporation of various saturated fatty acids.  相似文献   

13.
Trifluoromethanesulfonic acid (TFMSA) was used to reduce the high free fatty acids (FFA) content in sludge palm oil (SPO). The FFA content of SPO was converted to fatty acid methyl ester (FAME) via esterification reaction. The treated sludge palm oil was used as a raw material for biodiesel production by transesterification process. Several working parameters were optimized, such as dosage of catalyst, molar ratio, reaction temperature and time. Less than 2% of the FFA content was the targeted value. The results showed that the FFA content of SPO was reduced from 16% to less than 2% using the optimum conditions. The yield of the final product after the alkaline transesterification was 84% with 0.07% FFA and the ester content was 96.7%. All other properties met the international standard specifications for biodiesel quality such as EN 14214 and ASTM D6751.  相似文献   

14.
在固体碱催化下,由菜籽油改性制得的菜籽油脂肪酸甲酯与聚乙二醇400(PEG400)进行酯交换反应,合成了绿色可降解的多功能非离子表面活性剂聚乙二醇脂肪酸酯。对酯交换反应的主要影响因素和产物性能进行了考察。结果表明,在m(菜籽油脂肪酸甲酯)∶m(PEG400)=2.0∶1.0,催化剂w(CaO/ZrO2)=0.8%(相对于反应物总质量),温度130℃,反应时间7.5h的条件下,聚乙二醇脂肪酸酯产率达91.56%;产物浊点53℃、表面张力35mN/m、乳化性361s、润湿力59s,说明具有很好的表面活性。  相似文献   

15.
The acid lipase of castor bean endosperm catalyzed the hydrolysis of fatty acids from the 1 and 3 positions of synthetic glycerides immediately after achieving proper reaction conditions, but fatty acids from the 2 position were not detected in the reaction products until 7 to 10 min later. Results obtained with 2,3-butane dioleate, n-hexyl oleate and 2-hexyl oleate showed that the castor lipase does not cleave secondary ester linkages. These findings suggest that the acid lipase of the castor bean may catalyze hydrolysis of fatty acids from the 1 and 3 positions of triglycerides only; the steady appearance of 2 position fatty acids in the reaction products during lipolysis is probably the result of an apparent isomerization reaction. So. Utiliz. Res. Dev. Div., ARS, USDA.  相似文献   

16.
Separation of sterols and tocopherols from fatty acids in deodorizer distillate was facilitated through lipase-catalyzed modification of fatty acids in canola, mixed and soya deodorizer distillates. The fatty acid esterification with methanol catalyzed by SP-382 (an immobilized nonspecific lipase) proceeded rapidly, with conversion of fatty acid to methyl ester in 5 h being 96.5, 83.5 and 89.4%, respectively. A model mixture of pure oleic acid and dl-α-tocopherol was used to study any potential side reactions that may lower the tocopherol content during the esterification reaction. Under the conditions employed, the loss of tocopherol was less than 5%. Simple vacuum distillation (1–2 mm Hg) was employed to remove the volatile fraction (methyl esters of fatty acids, some fatty acids and other volatiles) of the esterified deodorizer distillate, leaving behind sterols, sterol esters and tocopherols. Sterols and tocopherols were almost completely retained in the residue fraction with recoveries in the range of 95%. Overall recoveries of sterols and tocopherols after esterification and distillation were over 90% for all the deodorizer distillate samples.  相似文献   

17.
Meadowfoam dimer acids have been prepared in a thermal clay-catalyzed reaction. Reaction conditions have been optimized, and yields of 44% were obtained with 2% water and 6–8% of an acid-washed montmorillonite clay, based on the meadowfoam fatty acids. Purity of the distilled dimer acids was 79–89% with most of the remaining 11–22% being residual mono- and tribasic acids. Dimethyl, di-(2-ethylhexyl), and di-n-butyl meadowfoam dimer ester derivatives were also prepared. Color, viscosity, and wear-preventive characteristics of the meadowfoam dimer acids and dimer ester derivatives were compared to those of commercial dimer acids and dimer esters. The viscosity of the meadowfoam dimer acids is similar to that of Empol® 1010, which is also derived from a highly monounsaturated fatty acid source. Viscosities of the meadowfoam dimer esters were also comparable to those of commercial dimer esters. Wear prevention characteristics, as determined by the four-ball test method, of the meadowfoam dimer acids and dimer esters were similar to those of the commercial products. In one case, the di-n-butyl esters, the meadowfoam derivative showed a significantly smaller wear scar than that shown by the di-n-butyl derivative of Unidyme® 14.  相似文献   

18.
樊国栋  沈茂 《应用化工》2008,37(1):93-96
综述了植物油改性合成聚乙二醇脂肪酸酯的催化剂研究进展。提出采用固体碱为催化剂进行脂肪酸酯类化合物与聚乙二醇酯交换反应来制备聚乙二醇脂肪酸酯基的方法。指出固体碱催化剂在此酯交换反应中的优良性能和应用前景。  相似文献   

19.
The Diels-Alder reaction between alkali conjugated and elaidinized safflower oil fatty acids and maleic anhydride was studied under various experimental conditions. The principal product which was obtained in 51–55% yields was a mixture of the adduct of maleic anhydride and maleic acid in 40∶60 proportions. The isolation and properties of this mixed adducts from the reaction mixture and their conversion to trimethyl, tributyl and triallyl esters are described. The trimethyl ester was also obtained in good yield from the methyl esters of the fatty acids and dimethyl maleate.  相似文献   

20.
The serum fatty acid profiles of patients receiving either intravenous medium or long chain triglycerides were studied. Seventeen hospitalized patients, dependent on total parenteral nutrition, were randomly enrolled into a prospective study. The total parenteral nutrition (TPN) delivered amino acids and glucose and either a 75% medium chain triglyceride and 25% long chain triglyceride (MCT group) physical mixture or all long chain triglyceride (LCT group), as the respective fat sources. The amino acids and glucose were given continously, and the lipid was given for 10 hours each day over five days. Fatty acid profiles on serum triglycerides and free fatty acids were done in the morning before any lipid was given and also later in the afternoon, near the end of the lipid administration, on days 1, 3 and 5. Medium chain fatty acids rose quickly in the triglyceride fraction in patients given MCT. Rapid MCT hydrolysis occurred as evidenced by the appearance of medium chain fatty acids in the free fatty acid fraction in the afternoon sampling. Clearance of the hydrolyzed medium chain free fatty acids (MCFFA) occurred so that little, if any, were present in the morning sampling one day later. Long chain fatty acids, as either triglycerides or free fatty acids, showed expected increases during the daily infusion, but not of such relative magnitude as the medium chain fatty acids. Medium chain fatty acid incorporation into the phospholipid or cholesterol ester fractions by the end of the five-day feeding period was present but minimal. As opposed to conventional long chain triglycerides, intravenously administered medium chain triglycerides are hydrolyzed and cleared rapidly and do not accumulate in other lipid fractions, and are therefore a more readily available lipid fuel.  相似文献   

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