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用乙醇和叔丁醇在稀疏酸催化下得乙基叔丁醚粗产物。再经多次水洗、干燥、金属钠回流后,重蒸,即得无醇的乙基叔丁醚。 相似文献
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以环氧氯丙烷和叔丁醇为基本原料,经加成反应和环化作用,合成了缩水甘油基叔丁基醚(TBGE);用正交实验方法优化了TBGE的合成条件,气相色谱法分析了产品中TBGE含量,GC-MS和FT-IR等表征了产物结构.结果表明,在以BF3-乙醚为催化剂时,合成TBGE的适宜条件为:加成反应的温度和时间分别为50.0℃和5.0h,... 相似文献
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Muhammad Umar Yahia Abubakar Al-Hamed Abdulraheem Al-Zahrani Hisham Saeed Bamufleh 《中国化学工程学报》2013,21(10):1121-1128
Liquid phase synthesis of one of the important fuel oxygenate, ethyl tert-butyl ether (ETBE), from etha-nol and tert-butyl alcohol (TBA) has been studied in catalytic distillation column (CDC) using ion exchange resin catalyst CT-145H. A packed CDC of 1.2 m height and 50 mm diameter with indigenously developed reactive sec-tion packing was used to generate experimental data. Effect of different key variables on product purity in distillate, was investigated to find the optimum operating conditions for ETBE synthesis. The optimum conditions for 0.2 kg·s-1 of ethanol feed were found:reboiler duty of 375 W, molar feed ratio of 1︰1.3 of reactants, and reflux ratio of 7. Concentration profiles for each component along each column section at optimum conditions were also drawn. Neither output nor input multiplicity was observed at experimental conditions. 相似文献
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高取代度木薯羧甲基淀粉的合成及表征 总被引:1,自引:0,他引:1
以机械活化60min的木薯淀粉为原料,采用乙醇溶剂法合成了高取代度的木薯羧甲基淀粉.通过正交实验优化羧甲基淀粉的合成工艺条件,探讨了反应时间、反应温度、催化剂用量、醚化剂用量、乙醇浓度及淀粉乳浓度等因素对羧甲基淀粉取代度的影响.结果表明,其合成的最优工艺条件为:反应温度50℃,乙醇浓度90%,反应时间120min,ClCH2COOH与淀粉摩尔比0.80,淀粉乳浓度35%(ω),NaOH与淀粉摩尔比0.80.在此条件下合成的羧甲基淀粉的取代度为1.24.并对产物的结构进行了表征. 相似文献
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研究了以乙醇和氯甲基二甲基氯硅烷为原料合成氯甲基-乙氧基-二甲基硅烷的实验方法。探讨了反应溶剂、反应温度和氯化氢去除方式等影响因素,得出了适宜的反应条件:反应溶剂为石油醚,反应温度65℃,用尿素做缚酸剂去除氯化氢,收率92%,产物纯度98%。 相似文献
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Extraction and Fermentation‐Based Purification of Saponins from Sapindus mukorossi Gaertn. 下载免费PDF全文
Wu Heng Zhang Ling Wang Na Guo Youzhi Weng Zhen Sun Zhiyong Xu Deping Xie Yunfei Yao Weirong 《Journal of surfactants and detergents》2015,18(3):429-438
In the present study, the extraction and purification of saponins from Sapindus mukorossi Gaertn. were examined for effective utilization of the saponin resource. Saponins were extracted from S. mukorossi Gaertn. using water. The conditions of the water extraction process, including extraction temperature, extraction time, number of times of extraction, and solvent‐material ratio were optimized. The yield of total Sapindus saponins (TSS) from the pericarp was 33.41 % and its purity in the extract was 45.71 %. The saponin solution was further concentrated to 1/6–1/7 of its original volume, and dried yeast BV818 that adapted to the concentrated Sapindus saponins solution (SW) was screened. The activation conditions, inoculum amount, fermentation temperature, and fermentation period were optimized. By using the dried yeast under optimized conditions, the purity was increased to 75.50 %. The yield of the byproduct ethanol was 5.33 % (w/v), while the content of TSS in the final product decreased from 18.29 to 15.30 % (w/v). These results could contribute to the development of industrial‐scale production of Sapindus saponins. 相似文献
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以1-苄基-2-氧代吲哚-3-亚氨基甲酸叔丁脂和4-取代(Z)-N-苯基苯甲酰氯为底物通过1,3-偶极环加成反应合成了9种目标产物。通过比较目标产物的产率,对反应溶剂、碱及其用量、温度等因素进行了优化,确定了最佳反应条件,即在25℃下以二氯甲烷为溶剂、三乙胺为碱,且n(Et3N)∶n(1-苄基-2-氧代吲哚-3-亚氨基甲酸叔丁脂)=2.0∶1.0时,目标化合物最高产率可达94.4%。将具有生物活性的三氮唑骨架引入到螺环氧化吲哚骨架中,为更好地发现具有生物活性的该类新化合物提供借鉴。 相似文献
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以叔丁醇为原料,优化了其与浓盐酸氯代合成叔丁基氯的反应,采用CaCl2 氯化盐助催化体系使反应收率提高到95%,产品质量分数为99%;3,3-二甲基-1-丁烯合成的关键步骤是叔丁基氯与乙烯反应制备3,3-二甲基-1-氯丁烷,探讨了催化剂用量、反应温度对反应收率的影响.反应以无水三氯化铝为催化剂,用量为n(AlCl3):n[(CH3)3CCl]=0.018:1,反应温度为-17~-20 ℃时,产物3,3-二甲基-1-氯丁烷的收率可达80%;最后由3,3-二甲基-1-氯丁烷脱氯化氢制备3,3-二甲基-1-丁烯.考察了不同溶剂对反应收率的影响,以聚乙二醇-400为溶剂,无需加入相转移催化剂,收率可达88.5%,3,3-二甲基-1-丁烯的质量分数为可达95%以上. 相似文献
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以乙醇为溶剂,单甲氧基聚乙二醇琥珀酰亚胺碳酸酯(mPEG-SC)为修饰剂,对胰高血糖素样肽-1(GLP-1)进行了修饰反应条件的优化,同时对单修饰产物Mono-PEG-GLP-1进行分离纯化,并考察了其体外稳定性和体内活性. 得到的优化反应条件为:GLP-1浓度1 mg/mL, mPEG-SC与GLP-1摩尔比1:1, 37℃下反应24 h,该产物最高转化率达77%. 采用冷冻离心方式对Mono-PEG-GLP-1进行初步分离和浓缩,然后经反相液相色谱进一步高效纯化,纯度可达97%以上. 体外实验表明,Mono-PEG-GLP-1在血清中具有更好的稳定性及更强的抗胰蛋白酶消化能力. 体内动物实验表明,Mono-PEG-GLP-1具有更好的降血糖作用. 相似文献
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Separation of aqueous ethanol solution was carried out by pervaporation using a membrane which consisted of common polymer membranes. A membrane obtained from poly(tert-butyl methacrylate-co-styrene) was effective for a selective separation of ethanol from aqueous ethanol solution by pervaporation technique. The pervaporation ethanol–water mixture through the present membranes was analyzed as a solution–diffusion process, on the assumption that the both diffusion coefficients of each component are an exponential function of ethanol concentration. 相似文献
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