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稀土固体超强酸SO2-4/TiO2/La3+合成氯乙酸异丙酯 总被引:3,自引:0,他引:3
以稀土固体超强酸SO4^2-/TiO2/La^3 为催化剂,氯乙酸与异丙醇为原料合成氯乙酸异丙酯,系统地研究了投料比、催化剂用量、反应时间诸因素对产品收率的影响。实验结果表明:SO4^2-/TiO2/La^3 是合成氯乙酸异丙酯的良好催化剂,在n(异丙醇):n(氯乙酸)=3.0,催化剂的用量为氯乙酸质量分数的4.5%,环己烷的用量为反应物总摩尔分数的25%,反应时间4.0h,反应温度90~100℃,氯乙酸异丙酯的收率达到90.7%。 相似文献
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稀土固体超强酸SO42^-/TiO2/La^3+合成氯乙酸丙酯 总被引:1,自引:0,他引:1
本文研究了以稀土固体超强酸为催化剂 ,氯乙酸与丙醇反应合成氯乙酸丙酯。考察了诸因素对酯收率的影响。实验结果表明 :SO2 -4/TiO2 /La3 +是合成氯乙酸丙酯的良好催化剂。最适宜的反应条件为 :氯乙酸与丙醇的量比为 1∶1.5 ,催化剂的用量占反应物总重量的 2 .5 % ,反应温度 10 0~ 110℃ ,反应时间 2h ,在上述条件下 ,酯收率达到 87.1%。 相似文献
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本文比较了一水合硫酸氢钠、对甲苯磺酸、十二水合硫酸铁铵、稀土固体超强酸合成氯乙酸甲醋的催化活性;研究了以氯乙酸和甲醇为原料,以稀土固体超强酸为催化剂合成了氯乙酸甲酯.并考察了酸醇摩尔比、催化剂的用量、以及反应时间对酯收率的影响。结果表明:当氯乙酸与甲醇的摩尔比为1:4,固体超强酸1.8g,反应温度85~90℃,反应时间3.5h时为最佳条件.酯收率达到92.5%。 相似文献
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利用十六烷基三甲基溴化铵催化氯乙酸和邻甲苯酚合成邻甲苯氧乙酸,十六烷基三甲基溴化铵具有较高的催化活性,可以加快合成邻甲苯氧乙酸。反应过程考察了邻甲苯酚与氯乙酸摩尔比、催化剂用量、反应时间、反应温度对产率的影响以及催化剂的重复使用性能。反应的最佳条件为:在85℃下,邻甲苯酚和氯乙酸的摩尔比为1∶5,催化剂质量为0.3 g,反应时间为3.5h。此反应所得到的邻甲苯氧乙酸的产率为47.07%。该催化剂的用量很少,而且易于回收,并且可以重复使用。 相似文献
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利用十六烷基三甲基溴化铵催化氯乙酸和对甲苯酚合成对甲苯氧乙酸,十六烷基三甲基溴化铵具有较高的催化活性,可以加快合成对甲苯氧乙酸。考察了对甲苯酚与氯乙酸摩尔比、催化剂用量、反应时间、反应温度对产率的影响以及催化剂的重复使用性能。反应的最佳条件为:在80℃下,对甲苯酚和氯乙酸的摩尔比为1∶2,催化剂质量为0.2 g,反应时间2.5 h,此反应所得到的对甲苯氧乙酸的产率为51.93%。该催化剂的用量很少,易于回收,并且可以重复使用。 相似文献
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α-萘乙酸合成工艺研究 总被引:2,自引:0,他引:2
以荼与氯乙酸为原料,纳米级复合金属混合物Fht为主催化剂,KBr为助催化剂,采用直接缩合法制备了α-萘乙酸,讨论了原料配比、催化剂、反应时间及升温速度等因素对反应的影响,获得了较佳反应条件。合成α-萘乙酸较佳反应条件为:萘与氯乙酸摩尔比为3:1,Fht-1与KBr重量比为1:3,Fht-1用量为萘量的0.52%,4h升至反应温度.反应温度为180℃~224℃,反应时间为25h。在较佳反应条件下,产品收率为61.4%,熔点为118.5℃~129℃。 相似文献
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Models of chemical reaction systems can be quite complex as they typically include information regarding the reactions, the inlet and outlet flows, the transfer of species between phases and the transfer of heat. This paper builds on the concept of reaction variants/invariants and proposes a linear transformation that allows viewing a complex nonlinear chemical reaction system via decoupled dynamic variables, each one associated with a particular phenomenon such as a single chemical reaction, a specific mass transfer or heat transfer. Three aspects are discussed, namely, (i) the decoupling of reactions and transport phenomena in open non-isothermal both homogeneous and heterogeneous reactors, (ii) the decoupling of spatially distributed reaction systems such as tubular reactors, and (iii) the potential use of the decoupling transformation for the analysis of complex reaction systems, in particular in the absence of a kinetic model. 相似文献
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《Journal of the European Ceramic Society》2022,42(15):7377-7380
In this paper, we solve the long-unsolved problem of whether β-Ta4AlC3 can be transformed from α-Ta4AlC3. By utilizing Ta, Al, and C as initial materials with molar ratios ranging from 4.0/1.2/2.6–4.0/2.0/2.6, it is shown that the synthesis of β-Ta4AlC3 is largely affected by the content of Al, and it is confirmed that α-Ta4AlC3 is stable at 1600 °C. Furthermore, by modifying the sintering temperature of the samples (4.0/1.2/2.6, 4.0/1.4/2.6, and 4.0/2.0/2.6) from 1450 °C to 1600 °C, the reaction paths of α-Ta4AlC3 and β-Ta4AlC3 are systematically investigated. It is determined that the β-Ta4AlC3 phase forms through the reaction among Ta2C, C, and Ta0.6Al0.4 and the reaction between Ta2AlC and TaC. For the α-Ta4AlC3 phase, there are also two reaction pathways: one from the reaction among Ta2C, C, and Ta0.6Al0.4, and the other from the combination among Ta3Al2C, Ta2C, C, and TaC. 相似文献
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本文综述了国外双环戊二烯反应注射成型(DCPD RIM)的研究近况,主要介绍了原料的准备、加工过程、加工设备及制品改性方面的研究,对制品的性能和用途作了简单说明,同时对这一体系的发展进行了展望。 相似文献
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将活化后的活性炭置于密封的反应炉内,在高温还原气氛以及脱灰介质与催化剂的作用下,活性炭中的矿物质与脱灰介质发生反应,生成气态物排出炉外。利用该工艺可使活性炭的灰分降到1%~5%,脱灰率达85%以上 相似文献
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乙烯气相氧乙酰化反应机理和动力学研究 总被引:6,自引:2,他引:4
采用阶跃应答技术研究了乙烯Pd-Au-KAc/SiO2催化剂上气相氧乙铣化合成蜡酸乙烯过程主副反应的机理,结果表明:分子态吸附氧是生成目的产物醋酸乙烯的氧源,而原子态吸附氧是生成副产物二氧化碳的氧源,在工业条件下,主副反应动力学方程仅是氧化压的函数,主反庆级数为1级,副反应级数为0.5级,在反应机理研究的基础上,进一步研究确定了乙烯气相氧乙酰化过程的反应的网络和动力学参数。 相似文献
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Byeong-Il Non Byung-Hyun Moon Tae-Kyung Yoon Jong-Hyun Kim 《Korean Journal of Chemical Engineering》1995,12(5):551-556
Diffusion accompanied by instantaneous chemical reactions in a multicomponent drop is modeled. The developed model is then
simulated for the case of absorption of one solute from a continuous phase into the drop, followed by fast reactions with
two different reactants existing in the drop. The results of the model are obtained by using Galerkin’s finite element method
and represented by unsteady concentration profiles of all components in the drop, the reaction front positions, and the cumulative
mass flux and the enhancement factor of the diffusing solute. The effects of the system parameters, such as diffusivities
of the solute and the reactants, the relative amount of the reactants in the drop, and the interfacial concentration of the
solute, on the calculated quantities are evaluated. 相似文献
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A numerical investigation of a catalytically stabilized thermal (CST) combustor was conducted for a multichannel catalyst
bed, and both the catalyst bed and thermal combustor were simultaneously modeled. The numerical model handled the coupling
of the surface and gas reaction in the catalyst bed as well as the gas reaction in the thermal combustor. The behavior of
the catalyst bed was investigated at a variety of operating conditions, and location of the flame in the CST combustor was
investigated via an analysis of the distribution of CO concentration. Through parametric analyses of the flame position, it
was possible to derive a criterion to determine whether the flame is present in the catalyst bed or the thermal combustor
for a given inlet condition. The results showed that the maximum inlet temperature at which the flame is located in the thermal
combustor increased with increasing inlet velocity. 相似文献