In—Situ FTIR Study on Effect of Lathanum on Oxidation Mechanism of Methanol Automobile Exhaust on Supported Palladium Catalyst

The performance of severe oxidation of methanol on 0.1%Pd supported on alumina was studied by a combined device of chromatograph-micro reactor,The results show that the addition of La intoγAl2O3as support can affect the performance of Pd catalyst greatly.By using Pd catalyst comtaining La in methanol oxidation,thouhg,the ignition temperature is not lower than than by using Pd catalyst,the presence of La does suppress the formation of oxygenic intermediates,The results by in-situ FTIR show that the presence of La in the support affects the adsorbed specties and hence the mechanism of severe oxidation of methanol on Pd catalyst.     

硝基苯催化加氢制对氨基苯酚

介绍了硝基苯经催化加氢对氨基苯酚的工艺路线，以及国外近几年地其中关键因素，如深度加氢、催化剂中毒以及表面活性剂等对反应的影响及改进情况。     

Nitric Oxide Reduction Performance of Automotive Palladium Catalysts

ＮｉｔｒｉｃＯｘｉｄｅＲｅｄｕｃｔｉｏｎＰｅｒｆｏｒｍａｎｃｅｏｆＡｕｔｏｍｏｔｉｖｅ Ｐａｌｌａｄｉｕｍ ＣａｔａｌｙｓｔｓＷａｎｇＸｉｎｇｙｉ（王幸宜）；ＬｕＧｕａｎｚｈｏｎｇ（卢冠忠）；ＷｕＳｈａｎｇｌｉａｎｇ（吴善良）（ＲｅｓｅａｒｃｈＩｎｓｔ...     

Study on Aldol Condensation of HCHO and CH3 CHO over MgO Catalysts Modified by Lanthanum and Cerium

Aldol condensation of HCHO and CH3CHO over MgO, modified MgO and Al2O3 with rare earth oxides,was studied. The measurement of adsorption of pyrrole on catalysts by in-situ FT-IR and NH3 TPD indicated thatthe addition of elements La or Ce into MgO increased the acidity of the solid. In-situ FI‘-IR showed that the activation of - C = O in HCHO adsorbed on CeO-MgO and La2O3-MgO occurred. The measurement of catalytic activity implied that the modified catalysts can promote the formation of pentaerythritol, dipentaerthritol and tripentaerythritol.     

新型甜味剂—二氢查尔酮衍生物

对二氢查尔酮类甜味剂的制备和应用作了一简要的概述,介绍了影响此类物质甜度的各个因素和二氢查尔酮衍生物的制备合成方法。同时,对柚皮甙二氢查尔酮和新橙皮甙二氢查尔酮两种甜味剂的性质、用途、合成方法、应用前景做了详细介绍。     

1,3-丙二醇的合成工艺进展

介绍并比较了 1,3-丙二醇的几种合成方法 ,讨论了丙烯醛法、环氧乙烷法、生物技术法和醇醛缩合法的合成路线及其工艺条件与催化剂的选择等     

3,3’,4,4’-联苯四甲酸二酐的合成

介绍了各种3,3’,4,4’-联苯四甲酸二酐的合成路线,包括4-氯(溴)-邻苯二甲酸(酐、酯、盐)的脱卤偶联法、邻苯二甲酸二甲酯的氧化偶联法、对苯二甲酰氯偶联法及其工艺特点,详细阐述了由钯催化对苯二甲酰氯与二硅烷直接一步反应制得3,3’,4.4’-联苯四甲酸二酐的方法,以及1,2-二氯四甲基二硅烷的主要制备方法,其中1,2-二氯四甲基二硅烷是合成3,3’,4,4’-联苯四甲酸二酐的重要试剂。     

三效催化剂涂层制备与性能研究

薄水锅石作为γ-Al₂O₃的前驱体,加入CeO₂-ZrO₂-La₂O₃和扩孔剂等助剂制备蜂窝陶瓷载体涂层,研究了涂层料液的表观粘度、因含量与载体负载量的关系,粘度对料液中粒径分布和涂层性能的影响,利用SEM、BET表面积、超声波震荡和热冲击等方法研究了涂层的性能.结果表明,涂层料液中适宜的固含量为30％～40％;一次浸量>二次浸量>三次浸量,适宜的负载量为8％～15％;低粘度料液以小颗粒为主,颗粒分布均匀,制备的涂层有较好的抗震动和抗热冲击性能;高粘度涂层料液的颗粒较大和粒径分布较宽,有利于提高载体的负载量,但涂层的性能明显下降.堇青石蜂窝陶瓷载体经一步法负载涂层后,可获得约 50 m²/g的表面积.     

Effect of Lanthanum on Methanol Fuel Exhaust Deep Oxidation over Palladium Catalyst

The performance of deep oxidation of methanol on supported Pd catalyst was examined by a chromatograph-micro-reactor. The results show that the addition of La into γ-Al2O3 support can affect greatly the performance of the Pd catalyst. In the absence of CO, La can decrease the content of oxygen-containing intermediate, although La can not lower the light-off temperature of methanol oxidation. In the presence of CO, La can lower the light-off temperature, decrease theamount of CO adsorption, and weaken evidently “CO inhibition“ to the oxidation of methanol. By XPS technique, it is shown that La modifies the electronic structure of Pd, which attributes to the modifications of the catalytic performance.     

单季戊四醇与双季戊四醇的分离方法

综述了单季戊四醇与双季戊四醇的各种分离方法 ,以及各种影响因素