新型非晶态合金的制备及其催化葡萄糖、麦芽糖加氢的研究

【作者】 杨平锋；

【导师】 李和兴；

【作者基本信息】 上海师范大学 ， 物理化学， 2006， 硕士

【摘要】 非晶态合金催化剂由于其长程无序而短程有序的独特非晶态结构，导致其优良的催化活性、选择性，特别是在制备过程中的环境污染少，催化效率高的特点，越来越来引起人们的重视。尽管对非晶态合金催化剂的研究时间不长，但是大量的实验数据已经表明其良好的工业化应用前景。 本论文通过化学还原法制备超细Ru-Fe-B非晶态合金催化剂、双类金属三元非晶态合金催化剂（Co-P-B）和双类金属双金属四元非晶态合金催化剂（Ni-Co-P-B），以具有重要工业应用价值的液相葡萄糖、麦芽糖制备山梨醇、麦芽糖醇为探针反应，系统考察了上述催化剂的催化性能。在此基础上，结合催化剂的系统表征和催化反应动力学研究，一方面，深入研究了非晶态合金的结构、表面电子态和催化性能之间的关系；另一方面，通过改变修饰剂的种类和用量，阐述其与非晶态合金的相互作用及其对催化性能的促进作用。主要研究工作如下： 一、催化剂的制备： 采用化学还原法，一定温度水浴条件下，将一定量的KBH₄溶逐滴加入到（1）RuCl₃（或NiCl₂、CoCl₂）溶液；（2）RuCl₃和FeCl₃混合溶液；（3）CoCl₂（或NiCl₂）和NaH₂PO₂的混合溶液；（4）NiCl₂、CoCl₂、和NaH₂PO₂的混合溶液；得到黑色的沉淀，用去离子水洗至中性，最后得到（1）两元超细非晶态合金Ru-B（或Ni-B、Co-B）；（2）Ru-Fe-B；（3）双类金属三元非晶态合金Co-P-B（或Ni-P-B）；（4）新型双类金属双金属四元非晶态合金催化剂Ni-Co-P-B。 二、催化性能评价 在高压釜中加入一定量所制备的非晶态合金催化剂和葡萄糖或麦芽糖水溶液，在P_H2=3.0 MPa以及适当温度下进行催化加氢，观察釜内压力变化测定催化反应速率、采用液相色谱测定葡萄糖或麦芽糖的转化率以及对目标产物山梨醇或麦芽糖醇的选择性。结果表明，所有以上制备的非晶态合金催化剂对山梨醇的选择性均～100％；而且对麦芽糖醇的选择性～100％，远高于Raney Ni对麦芽糖醇的～75％的选择性，为工业上制备高纯度的麦芽糖醇提供一定的实验基础。葡更多还原

【Abstract】 Amorphous alloys is a new class materials at present with short-range ordering and long-range disordering structure which may provide pathways to the excellent catalytic properties, such as higher catalytic activity and selectivity, stronger resistance to the poison, especially low and even none environmental pollution in the course of catalysts preparation. These topics are still attracting because of the industrial requirements on the atomic reactions and green chemistry. Although the study of amorphous alloy catalysts was carried out only two decades, lots of experimental data have strongly shown a good potential for their industrialapplication.In this dissertation, both the ultrafine and supported Ru-Fe-B amorphous alloys,the bimetallic amorphous alloy （Co-P-B）, the bimetallic and bimetalloid amorphous alloy Ni-Co-P-B were prepared by chemical reduction. The catalytic performance of the amorphous alloy catalysts was measured during liquid phase hydrogenation of glucose or maltose to sorbitol or maltitol. The catalytic activity of the Ru-B amorphous alloy was further enhanced by adding Fe-dopant. The relationship between the structure, surface electronic state of the amorphous alloy and the catalytic performance was systematically studied based on a series of characterization of catalysts, together with the kinetic studies. Furthermore, changing the kinds of the additives and their amount in the amorphous alloys, the modification of several mixtures on the structure of the amorphous alloy has been investigated, which could account for their promoting effect on the catalytic behaviors. The researching work in the present dissertation could be summarized as follows:1. Catalysts preparation: By adding KBH4 into a solution containing （1） RuCl₃, （2） RuCl₃ and FeCl₃, （3） NiCl₂ （or CoCl₂）, （4） NiCl₂ （or CoCl₂） and NaH₂PO₂, and （5） CoCl₂ and NaH₂PO₂, （6） NiCl₂, CoCl₂ and NaH₂PO₂, the ultrafine amorphous alloys of Ru-B, Ru-Fe-B, Co-B, Ni-B, Ni-P-B, Co-P-B and Ni-Co-P-B were prepared, which更多还原