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1.
Hydrogenation of oleic acid to 9-octadecen-1-ol with rhenium-tin catalyst   总被引:1,自引:0,他引:1  
A new supported bimetallic catalyst, rhenium-tin, is able to reduce oleic acid to 9-octadecen-1-ol (cis andtrans isomers) with appreciable yield under mild hydrogenation conditions. This paper reports investigations on the effects of catalyst preparation methods, types of support, catalyst raw materials, mole ratio of the metals, activation and reaction conditions on the activity and selectivity of the catalyst. Catalyst derived from the combination of ammonium perrhenate and stannic chloride on alumina gave the best performance, and the presence of tin in the catalyst is essential for the preservation of the olefinic bond of the oleic acid during hydrogenation.  相似文献   

2.
A ruthenium/tin/alumina catalyst was found to hydrogenate ethyl phenylacetate to 2-phenylethanol selectively with a high yield. The optimum atomic ratio of ruthenium to tin was 1∶2, and the optimum metal content was about 5 and 11.75 wt% for ruthenium and tin, respectively. The raw materials of the catalyst had a significant effect on the conversion and selectivity in the catalytic hydrogenation. Chloride had a negative effect on catalytic activity. Washing the catalysts, which were prepared from chloride materials, with distilled water or alkali solution had a positive effect upon catalyst activity. The catalyst prepared from chloride-free raw materials performed the best, and the impregnation catalyst has a higher yield than the solgel catalyst, suggesting that impregnation is a suitable procedure for this reaction.  相似文献   

3.
A ruthenium-tin-alumina catalyst, prepared by a combination of kneading and impregnation methods, which we have named the combination method, was able to selectively hydrogenate ethyl phenylacetate to 2-phenylethanol; tin oxide was used as a chloride-free tin source. For this combination catalyst, the optimum atomic ratio for Ru: Sn was found to be 1 4. X-ray diffraction measurements showed the presence of tin particles. It appeared that the number of the tin particles had a large effect on the hydrogenation of C=O groups. However, the catalyst prepared with ruthenium oxide had a low activity, possibly owing to the ruthenium metal or ruthenium-tin alloy, which was formed and which obstructed the reaction.  相似文献   

4.
采用浸渍法制备硅胶(SG)/对甲苯磺酸(p-TSA)催化剂,并用XRD对其进行了表征。利用冰醋酸和无水乙醇为原料,以SG/p-TSA为催化剂合成乙酸乙酯。考察了反应时间,催化剂的用量,原料配比等对该反应的影响。最佳合成条件为:反应温度为100℃,反应时间为100 min,酸醇摩尔比为1.0∶1.9,催化剂用量为5%,产率为95.40%。催化剂不经处理可重复使用,使用3次以后的产率为81.11%。  相似文献   

5.
杜晓晗 《化学世界》2012,(3):169-171
以柠檬酸和2-乙基己醇为原料,用氧化二正丁基锡为催化剂合成了无毒增塑剂柠檬酸三(2-乙基)己酯,考察了反应温度、催化剂用量、醇酸摩尔比、反应时间等因素对反应结果的影响,对合成的产品进行了红外光谱分析。实验结果表明,氧化二正丁基锡催化合成柠檬酸三(2-乙基)己酯的最佳反应条件为n(柠檬酸)∶n(2-乙基己醇)=1∶3.60,催化剂用量为柠檬酸质量的0.5%,反应时间为120min,反应温度为150~160℃,在最佳反应条件下,柠檬酸三(2-乙基)己酯收率在98%以上。  相似文献   

6.
硅钨酸掺杂聚苯胺催化剂催化合成环己酮1,2-丙二醇缩酮   总被引:4,自引:0,他引:4  
采用回流法制备硅钨酸 (H4SiW12 O40 )掺杂聚苯胺 (PAn)催化剂H4SiW12 O40 /PAn。用环己酮和 1,2 丙二醇为原料合成环己酮 1,2 丙二醇缩酮 ,探讨了硅钨酸掺杂聚苯胺催化剂对缩醛反应的催化活性 ,较系统地研究了原料量比 ,催化剂用量 ,反应时间诸因素对产品收率的影响。实验表明 :硅钨酸掺杂聚苯胺是合成环己酮 1,2 丙二醇缩酮的良好催化剂 ,在n(环己酮 )∶n(1,2 丙二醇 ) =1∶14 ,催化剂用量为反应物料总质量的 1.6 % ,环己烷为带水剂 ,反应时间 5 0min的优化条件下 ,环己酮 1,2 丙二醇缩酮的收率可达 85 .6 %。  相似文献   

7.
以双三羟甲基丙烷与正辛酸为原料,对甲基苯磺酸为催化剂,采用酸醇酯化法合成了双三羟甲基丙烷正辛酸酯。考察了反应物投料比、反应时间、催化剂用量等对反应的影响。结果证明,最佳反应条件为:酸醇摩尔比4.4∶1,催化剂用量为双三羟甲基丙烷质量的1.0%,带水剂为双三羟甲基丙烷质量的60%,反应温度为120℃,加热回流4 h。在此工艺条件下,产品颜色浅,产率高达97.28%。并用红外光谱、核磁等方法进行了定性分析。  相似文献   

8.
己二酸系聚酯多元醇的合成   总被引:2,自引:0,他引:2  
以己二酸和不同多元醇为原料,经酯化、缩聚合成已二酸系聚酯多元醇。考察了醇酸摩尔比、催化剂种类和用量等因素对酯化反应的影响。研究表明,当采用四异丙基钛酸酯为催化剂,质量分数为总投料量的0.03%,醇酸摩尔比为1.2~1.3,反应温度为220℃,真空度为85~90kPa时,合成的己二酸系多元醇酯化率可达99%。  相似文献   

9.
酯交换-吸附脱乙醇联合工艺合成乙酸异辛酯   总被引:2,自引:0,他引:2  
以乙酸乙酯和异辛醇为原料、阳离子交换树脂NKC-9为催化剂,通过酯交换反应,采用4A分子筛吸附脱乙醇技术合成乙酸异辛酯,考察了原料配比、催化剂用量和反应时间等因素对酯交换反应的影响. 结果表明,较佳的酯交换反应工艺条件为:乙酸乙酯与异辛醇摩尔比3.0:1,NKC-9为初始原料质量的6.0%,反应温度≤98℃,反应时间4.0 h. 在该条件下,反应液中乙酸异辛酯含量为60.51%.  相似文献   

10.
王守庆 《应用化工》2005,34(6):369-370
以固体超强酸SO42-/TiO2为催化剂,以苯乙酸和月桂醇为原料,直接合成苯乙酸月桂醇酯,研究探讨了原料摩尔比、反应时间、催化剂用量等工艺条件对苯乙酸月桂醇酯收率的影响。结果表明,最佳反应条件为:醇酸摩尔比3.0∶1,催化剂用量5%,反应时间3h,酯化率可达90.8%。  相似文献   

11.
磷钨杂多酸掺杂聚苯胺催化合成环己酮乙二醇缩酮   总被引:1,自引:0,他引:1  
采用浸渍法制备的磷钨杂多酸掺杂聚苯胺H3PW12O40/PAn作催化剂,通过环己酮和乙二醇为原料合成环己酮乙二醇缩酮,探讨了磷钨酸掺杂聚苯胺催化剂对缩酮反应的催化活性,系统地研究了原料量比,催化剂用量,反应时间诸因素对产品收率的影响。实验表明,在n环己酮∶n乙二醇=1∶1.5(物质的量比),催化剂用量为反应物料总质量的0.25%,环己烷为带水剂,反应时间1.0 h的优化条件下,环己酮乙二醇缩酮的收率可达80.4%。  相似文献   

12.
以K2CO3、纳米CaCO3(自制)为原料,K2CO3的负载质量分数为50%,在750℃焙烧3 h得到纳米K2CO3/CaO固体碱催化剂,并通过XRD、FT-IR及TG-DSC等手段进行确认.再用该催化剂催化制备生物柴油,结果表明:制备生物柴油的最佳条件为温度70℃,质量分数3%的纳米K2CO3/CaO,醇油摩尔比12...  相似文献   

13.
张晓利  赵杨锋  闫俊 《应用化工》2012,41(7):1227-1228,1231
以9,10-二氢-9-氧杂-10-膦杂菲-10-氧化物(DOPO)和丙酮为原料,合成10-(异丙基-2-醇)-9,10-二氢-9-氧杂-10-膦杂菲-10-氧化物。考察了原料摩尔比、反应温度和反应时间对产物收率的影响。结果表明,较优工艺条件为:n(丙酮)∶n(DOPO)=12∶1,反应温度为50℃,反应时间为30 min时,DOPO的转化率为99%,目标产物收率为90%。  相似文献   

14.
介绍了以连三甲苯和氯代叔丁烷为起始原料 ,在自制的非均相催化剂W 1 0 0作用下一步合成3,4 ,5 -三甲基叔丁基苯的简便方法。经探索性试验、正交试验和单因素试验确定了最佳反应条件 :连三甲苯与氯代叔丁烷物质的量比为n连三甲苯∶n氯代叔丁烷 =1∶1 ,催化剂W 1 0 0的用量占连三甲苯的质量分数为 2 % ,反应温度 5℃ ,反应时间 7~ 8h ,在此条件下 ,3,4 ,5 -三甲基叔丁基苯的收率达到 79%以上  相似文献   

15.
Aggregation and related phenomena in nonaqueous binary and ternary solutions containing unsaturated long-chain fatty alcohol amphiphiles have been studied. Six C18 fatty alcohols were studied—oleyl alcohol (9Z-octadecen-1-ol), elaidyl alcohol (9E-octadecen-1-ol), linoleyl alcohol (9Z, 12Z-octadecadien-1-ol), elaidolinoleyl alcohol (9E, 12E-octadecadien-1-ol), linolenyl alcohol (9Z, 12Z, 15Z-octadecatrien-1-ol) and elaidolinolenyl alcohol (9E, 12E, 15E-octadecatrien-1-ol). Equivalent conductivity and photon correlation spectroscopy confirmed that unsaturated long-chain fatty alcohols form large and polydisperse aggregates in methanol. Critical micelle concentration (CMC) results showed that the degree of unsaturation and configuration of the double bonds in the fatty alcohol significantly influences aggregation. Aggregation of oleyl alcohol in a series of straight and branched medium-chainlength (C3-C8) alkanol solvents was studied. For shorter-chained alkanols (C1-C4), decreasing solvent dielectric constant decreases the CMC; however, for longer-chained alkanols (C4-C8), no significant effects occurred on the CMC. The effect of solubilized soybean oil on the viscosity of long-chain fatty alcohol/methanol solutions was also analyzed. Relative viscosity results were consistent with those expected for microemulsions. Although preliminary in nature, these results generally support the notion that soybean oil is solubilized by incorporation into large soybean oil-in-fatty alcohol aggregates in methanol solvent, resembling a nonaqueous detergentless microemulsion. Presented at the 67th Colloid and Surface Science Symposium, Toronto, Canada, June 20–23, 1993.  相似文献   

16.
张方  王璐  李春 《应用化工》2010,39(6):850-853
利用微波强化以棉籽油和甲醇为原料,KOH为催化剂制备生物柴油。考察醇油摩尔比、催化剂用量、反应时间和微波功率对酯交换反应的影响。结果表明,醇油摩尔比为9∶1,催化剂用量为1.0%,反应时间为3 min,微波功率360 W为最优反应条件。在此反应条件下生物柴油产率可达94%。与传统合成方法相比,该方法可缩短反应时间30~35 min。所得生物柴油主要质量指标达到我国和欧洲(EN14214)生物柴油质量标准,通过红外光谱分析表明,棉籽油生物柴油具有生物柴油所含的官能团。  相似文献   

17.
以邻苯二甲酸酐和异辛醇为原料、甲苯为带水剂,分别以NaHSO4、对甲苯磺酸、阳离子交换树脂、LaCl3、LaCl3/阳离子交换树脂、LaCl3/ZSM-5、LaCl3/活性炭等为催化剂合成邻苯二甲酸二异辛酯(DEHP),经过比较,确定以自制的5% LaCl3/ZSM-5作催化剂.通过正交实验确定最优合成条件为:邻苯二甲酸酐与异辛醇摩尔比1∶2.5、催化剂用量(以原料总质量计)5%、反应时间4h、带水剂用量(以原料总质量计)40%,在此条件下,邻苯二甲酸酐转化率达98.81%、邻苯二甲酸二异辛酯产率达96.97%,且催化剂具有较好的重复使用性.  相似文献   

18.
阳离子交换树脂催化合成异丁酸正丁酯   总被引:2,自引:0,他引:2  
以异丁酸和正丁醇为原料,阳离子交换树脂(NKC-9)为催化剂,合成了异丁酸正丁酯。考察了醇酸摩尔比、催化剂用量、反应时间等因素对反应的影响,并测定了动力学数据。通过实验得到了较佳制备工艺条件:n(正丁醇)∶n(异丁酸)=1.4∶1,NKC-9催化剂用量为异丁酸和正丁醇总质量的4%,反应温度≤125℃,反应时间2.0h,在该条件下,异丁酸的转化率达97.6%,催化剂重复使用5次后,异丁酸的转化率为96.4%。并建立了该酯化反应的表观动力学模型。  相似文献   

19.
The esterification of five medium- and long-chain acetylenic alcohols (2-nonyn-1-ol, 10-undecyn-1-ol, 6-octadecyn-1-ol, 9-octadecyn-1-ol, and 13-docosyn-1-ol), seven olefinic alcohols (cis-3-nonen-1-ol, 10-undecen-1-ol, cis-6-octadecen-1-ol, cis-9-octadecen-1-ol, trans-9-octadecen-1-ol, trans-9, trans-11-octadecadien-1-ol, cis-9, cis-12-octadecadien-1-ol), and four short-chain unsaturated alcohols (allyl alcohol, 3-butyn-1-ol, 3-pentyn-1-ol, and cis-2-penten-1-ol) with pentanoic or stearic acid in the presence of various lipase preparations was studied. With the exception of 2-nonyn-1-ol, where Lipase AY-30 (Candida rugosa) was used as the biocatalyst, the esterification of C11, C18, and C22 acetylenic alcohols with pentanoic acid appeared to be generally unaffected by the presence of an acetylenic bond in the alcohol as relatively high yields of the corresponding esters (78–97%) were obtained. However, medium- and long-chain olefinic alcohols were discriminated by Lipase AY-30, Lipolase 100T (Rhizomucor miehei), and especially by porcine pancreatic lipase (PPL), when esterification was conducted with pentanoic acid. Esterification of medium-and long-chain acetylenic or olefinic alcohols with a long-chain fatty acid, stearic acid, was very efficient except when Lipase AY-30 and Lipolase 100T were used. Short-chain unsaturated alcohols were much more readily discriminated. 3-Pentyn-1-ol and 3-butyn-1-ol were difficult (<5% yield) to esterify with pentanoic or stearic acid in the presence of Lipase AY-30 and PPL, respectively. Very low yields (<26%) of esters were produced when 3-butyn-1-ol and 3-pentyn-1-ol were reacted with pentanoic or stearic acid, when catalyzed by lipase from Candida cylindracea, No reaction took place between 3-butyn-1-ol and stearic acid in the presence of Lipase AY-30. Esterification of short-chain acetylenic and olefinic alcohols was most efficiently achieved with Lipolase 100T (Rhizomucor miehei), Lipozyme IM20 (Rh. miehei), or Novozyme 435 (Candida antarctica) as the biocatalyst.  相似文献   

20.
酶法制备一氯乙酸对硝基苄酯及催化反应动力学模型   总被引:1,自引:0,他引:1  
研究了固定化脂肪酶Novozym 435催化对硝基苄醇和一氯乙酸制备一氯乙酸对硝基苄酯的过程,并对酶法合成反应条件进行优化,确定最佳反应条件为:甲苯作溶剂,对硝基苄醇与一氯乙酸摩尔比1:2,对硝基苄醇浓度5 g L 1,Novozym 435脂肪酶浓度为3.4 g L 1,反应温度50℃,反应时间10 h,对硝基苄醇转化率为76.7%。最后探索酶催化合成一氯乙酸对硝基苄酯动力学反应,得出该反应动力学模型符合双底物乒乓机理和一氯乙酸底物抑制动力学模型的结论并写出了其动力学方程。  相似文献   

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