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摘要本文采用共沉淀法制备复合氧化物TiO2-ZrO2为载体，控制载体中Ti/Zr为1：1，并通过FT-IR、氮气吸附脱附和紫外漫反射等手段对复合氧化物载体做了表征。测定催化剂的比表面积，孔容大小，结构织构等。然后通过浸渍法，以镍为催化剂，在载体上负载镍催化剂，镍的含量为20%（ωt）。研究发现，催化剂中加入少量助剂对反应选择性和转化率有很大的提高。故本文以MgO和K2O为助剂，对催化剂进行改性，制备了多个组分催化剂，研究其催化性能，探索催化剂中助剂的含量对催化性能的影响，以及对比MgO和K2O助剂对催化剂活性的影响大小。本课题做了五组对比实验，探究不同催化剂组成对反应的影响的大小，选择最佳的催化剂组成。57465
催化剂的活性评价是在高压反应釜中进行，反应后上清液进行离心后用气相色谱仪对上清液进行定性定量分析，用面积归一化法计算催化反应后溶液中各组分的含量。通过各组分催化剂催化己二腈转化为己二胺的转化率，己二腈的选择性，己二胺的收率来分析催化剂对反应的活性大小。改变实验条件，通过改变反应温度，溶剂的量等实验条件，探索己二腈催化制己二胺的最佳工艺条件，催化剂催化性能的最佳条件。
本实验对催化剂进行FT-IR、氮气吸附脱附和紫外漫反射等手段对载体进行表征。实验结果显示，TiO2-ZrO2复合氧化物载体的比表面积、孔容较大，镍催化剂可以很好的分散在催化剂表面，并且以复合氧化物为载体的催化剂热稳定性好。助剂的加入对催化剂的活性有很大的改变。MgO和K2O助剂的加入会分散在载体表面，使催化剂的比表面积减小。K2O和MgO相比二者对比表面积的影响不大，K2O改性后的比表面积略低于MgO。
催化剂的活性评价实验结果表明，MgO催化己二腈的转化率比K2O作为助剂的催化活性更好。而随着MgO负载量的增加，己二腈的转化率提高，己二胺的选择性也明显提高。但有研究表明随着MgO负载量的逐渐增加，可能会减少镍催化剂的活性配位数量，从而降低催化剂的活性。温度对催化剂的活性实验表明，在温度为80℃时，己二腈的转化率和选择性同时达到最高，故此反应的最佳温度为80℃。反应时作为溶剂的乙醇与反应物己二腈的质量比也会对催化反应有一定的影响，本实验测得的最佳质量比为无水乙醇：己二腈=4：1。
毕业论文关键词：复合氧化物TiO2-ZrO2；镍催化剂；己二腈；己二胺
Abstract The coprecipitation of TiO2-ZrO2 composite oxide as a carrier, control vector Ti / Zr =1:1, and characterized by FT-IR, N2 adsorption desorption diffuse reflectance UV and other means of composite oxides were characterized. Catalyst for the determination of the specific surface area, pore volume, structural texture. Then by the impregnation method, using nickel as catalyst, on the carrier load nickel catalyst, nickel content is 20% (ωt). Study found that, catalysts with a small amount of additives on the reaction selectivity and conversion rate is improved greatly. Therefore, this paper with MgO and K2O as additives, the catalyst were modified to prepare Multiple group catalyst, and its catalytic properties were studied. To explore the effect of promoters in content on the catalytic performance, and comparison between MgO and K2O in the effect on the activity of catalyst size. This topic do the five groups of comparative experiments, exploring different catalyst components the size of the effect on the reaction, the best catalyst.
Catalyst activity evaluation is conducted in a high-pressure reaction kettle, after the reaction supernatant after centrifugation by gas chromatography of supernatant of qualitative and quantitative analysis, content of each component by area normalization method to calculate the catalytic reaction solution. Through each group pided into catalyst has dinitrile conversion rate for the conversion of hexamethylene diamine, adiponitrile selective, hexanediamine yield to analyze catalyst on the reaction activity of size. Changing experimental conditions, by changing the reaction temperature, amount of solvent and other experimental conditions and to explore the optimum conditions of adiponitrile catalysis of hexamethylene diamine and catalytic performance of the optimum conditions.