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离子交换树脂在酯化反应中的应用 总被引:13,自引:0,他引:13
评述了各种离子交换树脂在催化酯化反应中的应用。介绍了用树脂催化制备乳酸酯、甲酸酯、乙酸酯、丙酸酯、丁酸酯、丙烯酸酯等几十种酯化合物的工艺条件及效果。 相似文献
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对近十年磷钼酸及其盐类和衍生物催化酯类化合物的合成方法进行了综述,详细综述了磷钼酸等新型催化剂催化合成草酸二丁酯、富马酸二甲酯、丙酸异戊酯、乙酸环己酯、乙酸苄酯、氯乙酸乙酯、己酸乙酯、乳酸正丁酯、乙酸乙酯、苹果酯、顺丁烯二酸二丁酯的方法和磷钼酸光催化降解性能。 相似文献
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无毒增塑剂的生产与应用 总被引:12,自引:0,他引:12
鲁凤兰 《精细石油化工进展》2006,7(9):40-45
详细介绍了无毒增塑剂的生产及应用,包括柠檬酸三丁酯、乙酰柠檬酸三丁酯、偏苯三酸三辛酯、偏苯三酸三甘油酯、均苯四酸四辛酯、二甘醇二苯甲酸酯、对苯二甲酸二辛酯、癸二酸二正己酯以及环氧大豆油;并对我国增塑剂行业的发展提出建议。 相似文献
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测试了不同结构的三羟甲基丙烷复合酯、季戊四醇复合酯及双季戊四醇酯与制冷剂R22,R134a,R410A的临界互溶温度,分析了复合酯中多元醇、二元酸和一元酸的结构变化对其与制冷剂互溶性能的影响,以及双季戊四醇酯中直链和支链脂肪酸的结构变化对其与制冷剂互溶性能的影响。结果表明:复合酯与制冷剂的互溶性能主要取决于复合酯的基本结构,复合酯中多元醇、二元酸和一元酸的变化未对其与R22,R134a,R410A的互溶性能产生显著影响;双季戊四醇酯的基本结构是其具备优异的与制冷剂互溶性能的重要因素;双季戊四醇酯中直链脂肪酸的含量越高、碳链越长,其与R134a的互溶性能越差;双季戊四醇酯中支链脂肪酸的含量越高、碳链越短,其与R134a的临界互溶温度越低,溶解能力越强。 相似文献
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《精细石油化工进展》2000,(10)
聚合酯 一篇关于用作新型润滑油基础油的聚合酯研制、性能及应用的综述,附参考文献9篇。这些聚合酯为(-烯烃与不饱和酯(一般为马来酸酯、富马酸酯)的共聚物或(-烯烃与马来酸酐共聚物的后酯化产物。讨论的主要内容包括:制造路线、物理化学性能(流变学、弹性流体力学膜 相似文献
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聚丙烯酸酯基有机-无机杂化材料的研究 总被引:3,自引:0,他引:3
综述了聚合物基有机-无机纳米杂化材料制备方法,包括溶胶-凝胶法、插层复合法、共混法、原位聚合法、纳米微粒原位生成法、微乳液聚合法等;较详细地介绍了聚丙烯酸酯基有机-无机杂化材料的研究,其中包括聚丙烯酸酯与二氧化硅复合,聚丙烯酸酯与二氧化钛复合,聚丙烯酸酯与层状纳米材料复合,聚丙烯酸酯与碳酸钙纳米粒子复合等方面的研究。 相似文献
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研究了ZnCl2催化剂催化草酸二苯酯脱羰基合成碳酸二苯酯反应,考察了反应温度、反应时间、草酸二苯酯和催化剂摩尔配比对碳酸二苯酯选择性、碳酸二苯酯收率和草酸二苯酯转化率的影响,确定了最佳的反应条件是反应温度280℃,反应时间3h,草酸二苯酯和催化剂摩尔配比是100∶0 5。运用MXXC、Benson等基团贡献法,对草酸二苯酯脱羰基反应的平衡常数进行了估算,得到KP=1 3×109。确定了草酸二苯酯脱羰基反应的副反应,发现水在草酸二苯酯脱羰基合成碳酸二苯酯体系的副反应中起到了关键性作用。草酸二苯酯在酸催化剂作用下易发生水解反应,水的存在有利于副产物苯酚和水杨酸苯酯的生成。因此,限制反应体系中水的含量有助于碳酸二苯酯的生成。 相似文献
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多元醇酯作为一种性能优异的合成基础油,广泛应用在航空发动机润滑油、精密仪器仪表油、齿轮油等领域。不断发展的航空发动机对多元醇酯的黏温性能、低温性能、热安定性、氧化安定性要求逐步提高。文章主要对多元醇酯基础油这些优异性能与结构的关系进行了总结概括,并根据航空润滑油规格标准的发展提出了多元醇酯基础油以后的发展趋势。 相似文献
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Yu. V. Maksimuk Z. A. Antonova V. V. Fes’ko V. N. Kursevich 《Chemistry and Technology of Fuels and Oils》2009,45(5):343-348
Measurements have been made on the kinematic viscosity at 20–80°C and on the upper heat of combustion of methyl esters of
fatty acids from rapeseed, mustard, and colza oils and the oil of oily radish, as well as the ethyl esters of rapeseed oil.
A method is proposed for calculating the viscosity of a mixture of esters from the fatty-acid composition. Matched data have
been obtained on the specific heat of combustion of plant oils and their esters. 相似文献
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介绍了可生物降解液压油概念,它的组成包括基础油和添加剂。可生物降解液压油主要研究方向集中在筛选和开发新基础油方面,添加剂的研究还处于起步阶段。文中详细总结了以植物油、改进植物油、合成酯、聚醇醚、聚甲基烯烃及其多种混合物作为基础油的可生物降解液压油研究进展。研制开发性能好、成本低的可生物降解基础油与可生物降解添加剂是今后的发展趋势。 相似文献
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Detection and monitoring of 3-monochloropropane-1,2-diol (3-MCPD) esters in cooking oils 总被引:5,自引:0,他引:5
Raznim Arni Abd. RazakAinie Kuntom Wai Lin SiewNuzul Amri Ibrahim Muhamad Roddy RamliRabeah Hussein Kalanithi Nesaretnam 《Food Control》2012,25(1):355-360
A series of refined palm oil products were collected from different refineries in Malaysia and were analysed for 3-MCPD esters content. Samples were analysed using acidic transesterification and quantification by Gas Chromatography-Mass Selective Detector (GC-MSD). This method is based on the Federal German Institute for Risk Assessment (BfR) Method 008 for 3-MCPD esters. Limit of Detection (LOD) for this method was 0.25 mg kg−1 and Limit of Quantification (LOQ) was 0.50 mg kg−1 3-MCPD esters were generally not detected in crude oils, but were found at trace levels in bleached oils. Deodorized or fully refined oils contained higher 3-MCPD esters. The values ranged from <0.25-5.77 mg kg−1 for palm oil products, whilst other cooking oils in the retail ranged from <0.25-2.45 mg kg−1. 相似文献
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《Food Control》2016
3-monochloropropane-1,2-diol (3-MCPD) and 2-monochloropropane-1,3-diol (2-MCPD) are intensively investigated food contaminants, which recently emerged as a serious problem within the discovery of high levels of their fatty acid esters in lipid samples. In order to monitor the concentrations of mentioned toxicants in edible oils and fats, several analytical methods have been developed so far. This paper presents the screening research on bound 3-MCPD and bound 2-MCPD contents in edible oils, fish oils (in the form of dietary supplements) and lipid fractions of margarines available on retail market in Poland. Applied SGS “3-in-1” methodology developed by Kuhlmann (2011) was based on mild alkaline transesterification reaction. MCPD esters were not detected in cold-pressed, non-refined edible oils. In all samples of refined oils and products, containing lipid fraction consisting of refined fats, bound 3-MCPD and 2-MCPD were detected. The highest amounts of analytes were present in lipid fractions of margarines and dietary supplements containing refined fish oils (7,3 and 5.5 mg kg−1 respectively). 相似文献
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The use of synthetic ester oils is presently an absolute necessity. Polyols ester type is the preferable synthetic lubricant to meet the demands of the lightweight gas turbine engine that used in civilian and military air crafts overcoming the lack ability of mineral lubricants. In this work, trimethylolpropanetributyrate, triheptanoate and trinonanoate esters were prepared using Dean Stark apparatus under specified optimum conditions verifying a conversion of 96.8–98.5% within 5.3–6.3?h. The esters were characterized by; i.r., elementary and average mean molecular weight determination, density, viscosity…etc. Some of their cordial properties were correlated to their chain length and some correlations were deduced. Comparison of these properties with the French Air specification 3514 (Nato 0–150) and those for the commercial turbonycoil 13B which is used for French aircrafts indicates that, some of the prepared esters are suitable as base turbine oils. These synthetic base oils may be blended with addition of the appropriate additives to produce final turbine oil for air crafts of speed regime coming towards supersonic. 相似文献
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生物柴油对低硫柴油润滑性的增进作用 总被引:1,自引:1,他引:0
用菜籽油、大豆油以及芸香籽油制备了多种脂肪酸低碳醇酯即生物柴油,用高频往复试验机法(HFRR)考察了生物柴油对低硫柴油润滑性的增进作用。研究结果表明,生物柴油对低硫柴油润滑性有增进作用,但添加质量分数在0.2%以下时效果不明显;柴油组分不同,对生物柴油的感受性也不同:对于馏分较重、粘度较大的柴油,生物柴油的添加量只需超过2.0%其润滑性就能满足标准要求(磨斑直径不大于460/μm);而对于馏分较轻、粘度较小的柴油,需添加4.0%~5.0%才能使其润滑性满足要求;生物柴油的烷氧基链长对其润滑性没有明显影响,而甘油单酸酯或游离脂肪酸等杂质能够显著提高其润滑性;以不同植物油为原料制备的生物柴油在较低的添加比例下对低硫柴油的润滑性没有明显的不同,超过2.0%以后略有差别。 相似文献
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对杨木粉与大豆油或脂肪酸甲酯在超临界甲醇中的共炼进行了研究,以验证油脂及其甲酯对杨木粉液化的促进作用。研究结果表明,大豆油及脂肪酸甲酯都对杨木粉的分解率有明显促进作用,且大豆油的促进效果要优于脂肪酸甲酯。更进一步研究表明,共炼能够同时提高木粉中纤维素、半纤维素和木质素的分解率,其中木质素的相对分解率提高幅度最大。生物质共炼产物在经过低温减压蒸馏、石油醚萃取分离后得到两部分:生物轻油,以油脂衍生物为主;生物重油,以杨木粉液化产物为主。如果原料中采用的油脂不饱和度越高,则产物中会含有越多的甘油二酯沸程的化合物,这部分甘油二酯沸程化合物主要是有油脂衍生物与杨木粉液化产物缩合而成。另外,共炼所得到的生物重油产率要远高于杨木粉在超临界甲醇中直接液化的产率,本文对可能的原因进行了分析。 相似文献
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