乙苯/乙烯烷基化反应中EA-8402分子筛催化剂的失活动力学研究

用内循环无梯度反应器,在593～633K范围内考察了在乙苯/乙烯进行定向烷基化反应合成对二乙苯时,EA-8402分子筛催化剂的失活行为,建立了相应的失活动力学模型: -da/dt=0.3271exp(-12.94/T)P_(EB)~(0.02)P_(E(?))~(0.383)·α这一模型可作为该反应的宏观动力学模型的补充。由失活级数d=1,按Levenspiel判据推断:其失活机理应该是不受内扩散阻力控制的平行-连串失活。     

A110－1－H／A110－1型氨合成催化剂在双筐并流合成塔中的使用

在双筐并流氨合成塔中使用了Ａ１１０－１－Ｈ／Ａ１１０－１型氨合成催化剂，使用寿命达１７４０天，累计产氨４３８３７８ｔ．该催化剂组合具有低温活性好、易还原、高催化活性、高抗毒能力、良好的热稳定性与破碎强度等优点．     

宽温耐硫变换催化剂制备工艺研究

利用催化剂活性评价、催化剂活性组分含量测定、Ｘ—光衍射等手段，研究了共浸法制备宽温耐硫变换催化剂制备工艺过程中载体氧化铝的吸水率、浸渍条件、煅烧温度等对催化剂性能的影响。     

流动床离子交换工艺在己二酸催化剂回收中的应用

介绍流动床离子交换装置回收催化剂的生产工艺，从交换装置的选择到运行，分析了流动床的优点、影响因素以及生产中应注意的问题和要求。     

Supported Vanadia Catalysts for Dehydrogenation of Ethylbenzene with CO2

Alumina supported vanadia catalysts (V/Al) for selective oxidehydrogenation of ethylbenzene with CO₂ were prepared by impregnation method. During preparation the effect of promoters and calcined temperature was investigated, it was found these two items had a strong influence on the activity of V/Al catalysts. Dehydrogenation reaction with CO₂ was happened in the fixed-bed reactor at 450 °C. Results showed that 15.2% ethylbenzene conversion and 99.2% styrene selectivity were acquired when V₂K/Al catalyst was used.     

甲缩醛空气氧化制甲醛催化剂的研制和工艺条件探讨

考察了铁钼催化剂对甲缩醛空气氧化制甲醛的催化性能。制备了多种不同钼铁比和第三、第四组分的催化剂,进行了活性评价和筛选,探讨了适宜的工艺条件范围。对于所选定的催化剂(钼铁比为1.82～1.88;铬铁比为0.1～0.38)在适宜的工艺条件(甲缩醛进料浓度4.5～5.5％;甲缩醛和氧气进料比1:2.0±0.2;空速12000～22000h~(-1);热点温度370～390℃)下,甲醛收率可达85％左右。     

湿浸法制备活性组分非均匀分布负载型催化剂过程的计算机模拟

对活性组分非均匀分布的负载型催化剂的湿浸法制备过程进行了计算机模拟,其模拟程度可适用于任意多个活性组分的浸渍。发现单组分浸渍时,通过控制浸渍时间可获得活性组分由薄到厚的蛋壳型分布和均匀分布,但通过预浸渍吸附至一定分布后,再在空白溶液中浸渍洗脱,控制洗脱条件也可获得蛋黄、蛋白型的分布;加入竞争吸附剂,进行双组分及多组分浸渍,通过控制浸渍溶液性质及浸渍时间可获得各种类型的活性组分分布,诸如蛋壳型、蛋白型、蛋黄型和均匀型。通过对制备过程参数(如竞争吸附剂的选择、各组分有效扩散系数、初始浓度、吸脱附速率常数等)与活性组分分布形式之间关系的分析,可实现对任一分布形式的催化剂的制备过程参数的优化。这对实际制备催化剂具有指导意义。     

酯对钼系Ziegler-Natta催化剂引发丁二烯聚合的影响

以MoCl_4(Mo)为主催化剂,甲苯氧基二异丁基铝(Al)为助催化剂,在加氢汽油溶剂中,研究了8种酯对丁二烯(Bd)聚合的影响。结果表明,凡是能够溶解在酯中的Mo与Al所组成的二元催化体系,大多能很好地引发Bd聚合,并有较高的催化活性。酯的主要作用是增加Mo在加氢汽油中的溶解性,对聚合物的分子量影响不大,对微观结构几乎无影响。     

负载型Au催化剂的研究进展

金一直被认为是一种相对惰性的化学元素，但是近年来的研究发现，金催化剂对于CO及VOCs的低温氧化表现出很高的催化活性。本文综述了近年来金催化剂研究的进展情况，系统介绍了金催化剂的制备方法，以及金催化剂在不同反应中的催化活性和反应的机理。     

Synthesis, characterization, and catalytic properties of polysiloxanes with pendant 4-(3-pyridinyl)butyl and 4-(1-oxypyridin-3-yl)butyl groups

New silane monomers with the pendant 4-(3-pyridine)butyl group have been synthesized by hydrosilation of 3-(3-butenyl)pyridine with Me _n Si(OEt)_3-n H (n=0, 1) using a platinum catalyst. Only -addition products were observed. The products were characterized by elemental analysis, infrared,¹H- and¹³C-NMR spectroscopy, and gas chromatography-mass spectrometry. Hydrolysis-polycondensation of the difunctional monomer with a basic catalyst, Me₄NOH, gave a mixture of cyclic oligomers, principally cyclic tetramer, and linear homopolymer. Under similar reaction conditions, the trifunctional monomer gave crosslinked material which was soluble in common organic solvents. The linear homopolymer and crosslinked polymer were trimethylsilyl end-blocked with hexamethyldisilazane. The cyclic and end-blocked polymers were characterized by elemental analysis and spectroscopic methods. Molecular weights of the polymers were obtained by end-group analysis using¹H-NMR spectral data, size exclusion chromatography, and direct insertion-probe mass spectrometry. The cyclic, linear, and crosslinked materials were N-oxidized withm-chloroperoxybenzoic acid and characterized by spectroscopic methods. The polymeric N-oxide derivatives were shown to be effective transacylation catalysts in the synthesis of mixed carboxylic acid anhydrides in immiscible solvents (H₂O/CH₂Cl₂) under phase-transfer conditions. The implications of the results on the mechanism of catalysis are discussed.