【作者】 陶然；

【导师】 张继炎；

【作者基本信息】 天津大学 ， 工业催化， 2004， 硕士

【摘要】 间-二硝基苯液相催化加氢法合成间-苯二胺是制取间-苯二胺的一条行之有效的工艺路线，该方法具有收率高、产品质量好、环境友好等优点。反应所使用加氢催化剂的研究对这一工艺路线的广泛应用具有重要的意义。负载型镍基催化剂以其价廉易得和活性高等优点，已被广泛应用于多种化合物的液相加氢反应中并展现出很好的催化性能，但迄今为止其在间-二硝基苯加氢还原上的应用却比较少见。为此，研究和开发对间-二硝基苯加氢反应具有高活性、高选择性和长寿命的负载型镍基催化剂是本课题的研究重点。本论文分别采用分步浸渍法设计和制备了一系列负载型镍基催化剂，利用BET、XRD、TEM、TPR和活性评价等多种研究方法系统地考察了不同助剂类型及含量等因素对镍基催化剂物化性质和反应性能的影响，研究了催化剂的稳定性并探讨了可能的失活原因。研究发现，在浸渍型镍基催化剂中，以SiO2为载体、镍含量为20wt%、焙烧温度为773 K、还原温度为723 K条件下，采用先浸渍方式制备的含氧化镧助剂和氧化钾助剂的双助剂镍基催化剂，具有较好的反应活性和选择性。在加氢活性、选择性和稳定性方面，较无助剂的镍基催化剂有了很大幅度的提高。在反应条件为以乙醇为溶剂，反应温度365K，反应压力(氢压)3.0MPa，原料与催化剂质量比为10：1的条件下，其中以SiO2为载体、镍含量为20wt% 、镧助剂含量为3wt%、 氧化钾助剂含量为3wt%的催化剂，在本实验研究所考察的催化剂范围内催化活性表现最好。反应1小时后，对间-二硝基苯转化率、间-苯二胺的选择性和收率，可分别达到99.3％、99.5％和98.8％。催化剂稳定性试验表明，K-La-Ni/SiO2-1催化剂可以重复使用八次以上不发生明显活性下降。更多还原

【Abstract】 The catalytic hydrogenation technology of m-dinitrobenzene in liquid phase is an attractive and elegant routine for the production of m-phenylenediamine, owing to the advantages such as high product yield, good product quality and much less pollution to environment. Thus, it is practically significant to develop a new catalyst with high catalytic property for m-dinitrobenzene hydrogenation. The supported nickel catalyst has been long-term used for some hydrogenation technologies, due to its lower cost, easy availability, ideal catalytic activity and environmental benefit. Up to now, however, few works about hydrogenation of m-dinitrobenzene over supported nickel catalyst has been reported. In this thesis, the supported nickel catalyst has been attempted to use for the hydrogenation of m-dinitrobenzene in order to find an effective catalyst with high activity, selectivity and long service life.A series of supported nickel-based catalysts for the liquid-phase catalytic hydrogenation of m-dinitrobenzene to m-phenylenediamine have been designed and prepared by the incipient impregnation methods. The effects of different types and contents of promoters on the physico-chemical properties of catalysts have been characterized, using the technologies of nitrogen adsorption-desorption (BET), X-ray diffraction (XRD), transmission electron microscopy (TEM), temperature-programmed reduction (TPR)， and the catalytic activities, selectivies and stabilities of the catalysts have been evaluated. It has been found that among the catalysts prepared by impregnation method, the nickel-based catalyst supported on SiO2 with the nickel content of 20wt% which is calcinated at 773K and reduced at 723K in hydrogen respectively, has showed the better activity and selectivity. Before impregnating nickel, the addition of La2O3 promoter and K2O promoter into Ni/SiO2 could enhance the activity, selectivity and stability of catalyst apparently.Under the reaction conditions: alcohol is used as solvent, the reaction temperature is 365 K, the pressure is 2.9 MPa, the weight ratio of m-dinitrobenzene to catalyst is 10:1, it is found that the activity of the nickel-based catalyst supported on SiO2 with 20wt% Ni, 3wt% La and 3wt% K2O is the best one among all the catalysts we researched in this work. After 1 hour, conversion of m-dinitrobenzene, selectivity and yield of m-phenylenediamine are 99.3％、99.5％和98.8％, respectively. The <WP=5>catalyst K-La-Ni/SiO2-1 could be utilized over 8 times without apparent decrease of catalytic performances.更多还原