新型催化剂在没食子酸月桂酯合成中的应用

以自制壳聚糖硫酸盐为催化剂，1，4-二氧六环作溶剂，由没食子酸和月桂醇合成没食子酸月桂酯，研究了影响催化酯化合成的各种因素，获得了最佳反应条件：月桂醇与没食子酸摩尔比取1.25：1，催化剂与没食子酸摩尔比0．40：1，反应温度126～128℃，反应时间10-12h，收率98.6％。以10倍60％乙醇重结晶可得到白色片状晶体没食子酸月桂酯。     

没食子酸月桂酯的合成新工艺

没食子酸月桂酯的合成新工艺陈琳＊伍贤（广东药学院药学系，广州５１０２２４）没食子酸酯类具有增强纤维蛋白和血栓的溶解及扩张血管、增加冠脉血流的作用，也是有效的血小板凝聚抑制剂。对心脑血管疾病、胃溃疡、哮喘、炎症等均有治疗作用［１］。其中没食子酸月桂酯...     

壳聚糖硫酸盐催化没食子酸异丙酯的合成

以壳聚糖硫酸盐为催化剂催化合成没食子酸异丙酯(iPG),研究了催化剂在没食子酸与异丙醇反应中的催化活性,考察了催化剂用量、醇酸物质的量比、反应时间、带水剂用量以及催化剂重复使用次数对酯收率的影响。实验的最佳合成条件:醇酸物质的量比8∶1,催化剂用量为0.8 g(没食子酸为9.4 g),带水剂用量为20 mL,iPG的收率可达90%以上。结果表明,壳聚糖硫酸盐作为催化剂用于合成没食子酸异丙酯(iPG)具有较好的催化活性和重复使用性。     

柠檬酸月桂醇酯的合成

以柠檬酸、月桂醇为原料，利用直接酯化法合成了柠檬酸月桂醇酯，并对催化剂、原料配比和反应温度等酯化反应的影响因素进行了详细讨论。     

癸二酸月桂醇酯的合成研究

在氯化亚锡作为催化剂的条件下,以癸二酸与月桂醇为原料合成了癸二酸月桂醇酯。对其合成工艺条件进行了探索和优化,优化的最佳反应条件是癸二酸、月桂醇摩尔比为1∶3.0,催化剂用量为癸二酸用量的2.5%,反应时间2 h,酯化产率可达97.80%。优化的合成方法具有反应时间短、产率高,对设备腐蚀性小等优点。     

食品抗氧化剂没食子酸丙酯的合成

研究了以硫酸氢钠为催化剂，没食子酸和正丙醇为原料合成没食子酸丙酯，并考察影响反应的因素。结果表明，没食子酸、正丙醇和硫酸氢钠摩尔比为1：14：0．058，反应时间5h是最佳的反应条件，酯收率达93．8％。     

没食子酸正辛酯合成工艺研究

研究了以没食子酸和正辛醇为原料合成没食子酸正辛酯的新工艺 ,讨论了正辛醇的用量、夹水剂的种类和过量正辛醇的循环使用次数对酯化反应的影响。正辛醇循环使用 4～ 8次时 ,没食子酸正辛酯的总得率为 79.53% 95.32 %。     

没食子酸丙酯的合成研究

本文以没食子酸和丙醇为原料合成了抗氧化剂没食子酸丙酯。最佳反应条件是：没食子酸和丙醇的摩尔比为4．6：1（mol/mol）,用乙酸丙酯为溶剂,催化剂浓硫酸的用量为5ml,反应时间6h,产品收率80．8％。     

APPLICATION OF A STOCHASTIC NETWORK PORE MODEL TO A CATALYST PELLET

A previously developed stochastic two-dimensional network pore structure model has been applied directly to a nickel/alumina commercial catalyst pellet. A technique has been devised to determine the pore diameter distribution function of cylindrical pore segments for any prescribed network dimension which will exactly replicate the experimentally observed mercury penetration curve for the pellet in the method of mercury porosimetry. This stochastic network representation for the catalyst pellet pore structure is superior to the classical parallel bundle model since it incorporates the element of pore interconnectivity. The model has been extended to investigate the phenomena occurring during the accumulation of a foulant deposit (e.g. coke in hydrocarbon catalysis) for the pore structure determined for a 10 × 10 set of network elements for the pellet under study. The analysis shows how the build-up of a deposit causes physical blocking of the smaller pores at quite low accumulations of foulant which results in inaccessibility of parts of the interior pore structure. This necessarily results in only partial filling of the pore structure with deposit, with a tendency for greater accumulation towards the pellet exterior. This kind of behaviour is not possible with the parallel bundle model. A detailed comparison of the two pore models in respect of accessible interior volume at various foulant accumulations is presented. The derived network model based upon the penetration curve gives an independent prediction of the mercury porosimeter retraction curve which is in reasonably close agreement with the experimental result, thus confirming the probable utility of the model in predicting and correlating other macroscopic properties of the catalyst pellet.     

新型蒽醌加氢催化剂的研制和工业应用

高活性、高选择性催化剂是解决葸醌法生产过氧化氢过程中瓶颈问题的根本途径。研制的新型钯催化剂,活性组分浸渍层薄,催化剂活性高及反应稳定性好,实验室模式评价实验和工业应用表明,研制的新型催化剂表现出良好的活性及选择性,其时空产率超过目前工业用的催化剂。     

APPLICATION OF A STOCHASTIC NETWORK PORE MODEL TO A CATALYST PELLET

A previously developed stochastic two-dimensional network pore structure model has been applied directly to a nickel/alumina commercial catalyst pellet. A technique has been devised to determine the pore diameter distribution function of cylindrical pore segments for any prescribed network dimension which will exactly replicate the experimentally observed mercury penetration curve for the pellet in the method of mercury porosimetry. This stochastic network representation for the catalyst pellet pore structure is superior to the classical parallel bundle model since it incorporates the element of pore interconnectivity. The model has been extended to investigate the phenomena occurring during the accumulation of a foulant deposit (e.g. coke in hydrocarbon catalysis) for the pore structure determined for a 10 × 10 set of network elements for the pellet under study. The analysis shows how the build-up of a deposit causes physical blocking of the smaller pores at quite low accumulations of foulant which results in inaccessibility of parts of the interior pore structure. This necessarily results in only partial filling of the pore structure with deposit, with a tendency for greater accumulation towards the pellet exterior. This kind of behaviour is not possible with the parallel bundle model. A detailed comparison of the two pore models in respect of accessible interior volume at various foulant accumulations is presented. The derived network model based upon the penetration curve gives an independent prediction of the mercury porosimeter retraction curve which is in reasonably close agreement with the experimental result, thus confirming the probable utility of the model in predicting and correlating other macroscopic properties of the catalyst pellet.     

有效反应区概念在催化剂颗粒级设计中的应用

将有效反应区概念引入催化剂颗粒级设计中,用来分析由于反应与传递交互作用所引起的一类问题——在实际体系中,催化剂颗粒内可能存在有效反应区和死区的情形。数值模拟的结果表明,在许多情况下,尤其对扩散控制的体系,催化剂颗粒内存在有效反应区和死区的情形。在这种情况下,采用不同的活性分布形式是避免死区扩大有效反应区的一个重要方法,尤其对放热反应,用适当的活性分布形式制成的催化剂有可能既满足反应器系统对颗粒尺寸的要求,又能得到很好的催化剂效率。     

大型压机应用粉末触媒合成优质高产金刚石新工艺的研究

经过40年的努力,有专家统计,我国已有年产20～30亿克拉人造金刚石的生产能力;经过10年左右的努力,有专家预计,我国人工合成的金刚石20％是由粉末触媒生产的。两组有意义的数字把我们带入近年发展起来的大型压机应用粉末触媒合成优质高产金刚石工艺研究的总结之中。文章较详尽地总结了安徽省“十五”攻关计划之一的应用粉末触媒合成优质高产金刚石新工艺的研究．并对实现优质高产实际指标进行了科学分析。     

当前我国新触媒的研究和应用

回顾了几十年来国内触媒的发展过程,论述了触媒质量跟合成金刚石的关系.详细地介绍了触媒的各组成元素的作用和选取方法,以及决定触媒质量的种种因素.从生产设备到冶炼方法,从浇铸成形到冲片质检,介绍了触媒的生产过程和经验.通过大量的对比实验,确定了第七十八套新触媒为优秀方案,并通过详细的实验数据进行论证.     

QCS耐硫变换催化剂在齐鲁资源优化项目中的应用

介绍QCS系列耐硫变换催化剂在中国石油化工股份有限公司齐鲁分公司第二化肥厂资源优化项目中的工业应用情况,结果表明:该系列耐硫变换催化剂具有易于硫化、低温活性好、活性稳定性高以及耐低硫能力强等特点,完全满足生产使用要求。