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直接法合成三甲氧基硅烷工艺研究 总被引:2,自引:0,他引:2
以硅粉、甲醇为原料、以氯化亚铜、氧化铜、铜粉混合物为催化剂直接合成三甲氧基硅烷,考察了硅粉粒度、反应温度、溶剂配比及甲醇流量对反应的影响。结果表明,直接法合成三甲氧基硅烷的最佳工艺条件为粒度硅粉60~200μm,V(溶剂):w(硅粉)=2:1,反应温度215℃,0.6(甲醇加入速度(L/h)/反应介质(L)(0.8时,产品收率达80%以上、选择性在85%左右。 相似文献
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为研发高效的催化剂和深入认识直接法合成三烷氧基硅烷反应的机理,采用水热合成法制备了纳米CuCl催化剂,并用于催化乙醇与硅粉直接合成三乙氧基硅烷。探究了硅粉粒度、反应时间、硅粉与催化剂混合物预处理温度和预处理时间等因素对硅粉转化率、三乙氧基硅烷选择性的影响。结果表明:硅粉粒度为0.074 mm(200目)、反应时间为2 h、硅铜预处理温度和时间分别为260℃和8 h时催化效果最佳,硅粉转化率为93.6%,三乙氧基硅烷的选择性达99.6%。同时,结合X射线衍射(XRD)、扫描电镜(SEM)和X射线能谱(EDS)等表征结果,探讨了催化剂预活化和反应过程失活的内在作用机制。 相似文献
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通过双(甲基二氯硅基)乙烷和乙醇进行醇解反应,制得双(甲基二乙氧基硅基)乙烷,研究了反应工艺对产物收率的影响,较佳工艺条件为:双(甲基二氯硅基)乙烷与乙醇的量之比为1∶4. 6,以二甲苯为溶剂,填料为直径3 mm的玻璃弹簧,反应温度90℃,氮气流量60 m L/min,乙醇中水分含量小于1 000×10-6。 相似文献
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《化学与粘合》2017,(3)
采用二步法合成3-异氰酸丙基三乙氧基硅烷。第一步以3-氨基丙基三乙氧基硅烷(224g,1.01mol)和碳酸二乙酯(132g,1.12mol)在-25℃反应,为避免硅基水解,乙醇钠需溶解在无水乙醇中(乙醇水含量要低于1%)置于滴液漏斗缓慢滴加30min,反应混合物搅拌2h,升至室温(20~25℃),加入1.3m L冰醋酸,调节p H值至中性后减压蒸出。第二步将装有40m L矿物油的圆底烧瓶加热至320~340℃,将[3-(三乙氧基硅基)丙基]氨基甲酸乙酯缓慢滴加到热油上,发生热裂解反应,利用高真空闪蒸技术得到3-异氰酸丙基三乙氧基硅烷,再次精馏得到目标产物,纯度98%(JC),收率可达74.3%。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献