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何坤荣 《精细与专用化学品》2005,13(14):31-31
由中国石油大学(华东)与山东省东营市康瑞石油化工有限责任公司合作完成的尿素低压均相催化法生产氨基甲酸甲酯(MC)中试项目近期通过山东省科技厅鉴定。 相似文献
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《制药原料及中间体信息》2005,(10):18-18
尿素低压均相法氨基甲酸甲酯工艺诞生;L-苏氨酸精制结晶新技术与设备;一种合成共轭亚油酸维生素C酯方法的研究;尿囊素合成新工艺的研究;12-去羟基阿奇红霉素制备工艺的研究。 相似文献
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The production of diethyl carbonate (DEC) from urea and ethanol was investigated in a batch process. The catalytic activities of many metal oxides were evaluated, the influences of various operation conditions on the DEC yield were explored, and the catalytic mechanism was also analyzed. Among the tested catalysts, ZnO showed the best catalytic activity toward DEC synthesis. The optimum reaction conditions were as follows: ethanol/urea molar ratio of 10, catalyst concentration of 6%, reaction temperature of 463 K, reaction time of 5 h and the reaction pressure of 2.5 MPa, respectively. The highest DEC yield was 14.2%. The reaction of producing N-ethyl ethyl carbamate (N-EEC) was the main side reaction in this process, which consumed both ethyl carbamate and DEC. It is necessary to remove DEC from the reactor as quickly as possible. 相似文献
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对由碳酸二甲酯与环已胺化合生成N-环已基氨基甲酸甲酯的反应进行了研究。考察了催化剂CaCl2水溶液的催化活性。讨论了反应时间和反应温度以及催化剂的量对N-环已基氨基甲酸甲酯产率的影响。 相似文献
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A semicontinuous process for the synthesis of methyl carbamate from urea and methanol was investigated in the autoclave without the catalyst. Some significant parameters were determined in terms of the methyl carbamate yield. The optimal reaction conditions were found at an initial molar ratio of methanol/urea of 6:1, a reaction temperature of 423 K, a flow rate of fresh methanol at 4 mL/min, a stirring speed of 800 rpm and a reaction time of 6 hours, respectively. A MC yield of 98.7 % was obtained at the optimal reaction conditions. Furthermore, the kinetics of this reaction were researched and the reaction activation energy was obtained as 110.498 kJ/mol. It was demonstrated that removing methanol containing ammonia from the autoclave and replacing it with continuously feeding fresh methanol resulted in a higher reaction rate and a high MC yield. 相似文献
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《化工学报》2009,60(12)
加压条件下,对反应耦合法清洁合成苯氨基甲酸甲酯(MPC)的催化剂进行了筛选,对反应工艺优化、催化剂的循环使用和表征等方面进行了研究.在筛选的催化剂中,Bu_2SnO是较为理想的催化剂.在反应物碳酸二甲酯(DMC)和二苯基脲(DPU)的摩尔比为10:1,催化剂Bu_2SnO的用量为2%,160℃时,反应2 h,MPC的收率达到98%,远高于文献结果(77%).催化剂Bu_2SnO循环使用4次后,催化活性基本不变.对反应前后的Bu_2SnO进行了FTIR、XPS和XRD表征,结果表明,反应后从釜液中用水作沉淀剂絮凝沉淀出的催化剂绝大部分仍为Bu_2SnO,并可能含有其他微量未水解的催化剂中间体. 相似文献
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本文系统总结了尿素合成过程的热力学模型,介绍了尿素生产过程中搞压甲胺冷凝器和尿素合成塔的数学主模拟的实现,模拟结果与生产实测值吻合较好。 相似文献