模型催化的制备与表征毕业论文.doc

毕 业 论 文 模型催化剂的制备与表征 院系名称：化学工程学院 专业名称：化学工程与工艺 学生姓名： 学 号： 指导教师： 完成日期: 2012年 6月6日模型催化剂的制备与表征 摘 要 在重质油的加工过程中，催化过程占到极大的比例。而催化过程的核心就是催化剂的开发与研究。工业上的催化剂孔结构复杂，表面性质不均一，催化剂的相关基础研究，例如催化剂内扩散研究需要有一种孔径均一，结构规整，表面性质基本相同的用于催化剂的研究。模型催化剂为解决这一问题提供了一个新的途径。 本文利用单分散二氧化硅微球的水悬浮液，采用蒸发和重力沉降两种组装法，制备四个平均孔径不同的SiO2模型催化剂载体，并采用VIH法，对其进行表面改性，制备出了表面性质类似于Al2O3的载体，进而担载NiMo活性组分得到孔径均一，结构规整的模型催化剂。 采用NH3-TPD和Py-FTIR表征了改性后的载体的酸性与酸量，采用XRD表征了改性前后活性组分在载体上的分散情况，使用Al27NMR研究了Al与Si的结合形式。结果表明，改性后的载体酸性主要以L酸为主，使得活组分在其上分散情况得到改善，Al主要是通过Al—O—Si的形式实现包覆的。 关键词：催化剂；制备；表征 Preparation, and characterization of model catalyst Abstract Catalytic process accounted for a great proportion in the processing of heavy oil refining.Obviously, catalyst is the core of catalytic process, so further study of catalyst is required. However, the pore structure and surface prosperties of industrial catalyst is so complexly that so many problem can not resloved .Therefor, the research of model catalysts with narrow and tunable pore size and same surface prosperties is a solution to this problem. In this paper, uniform pore size SiO2 supports were fabricated by ordered packing of monodisperse SiO2 spheres through evaporation assembling method or gravity sedimentation method, then fowllowed by calcination and hydrothermal treatment. In order to prepare the same chemical property support as the commercial alumina support ,the surface of SiO2 support was coated with Al2O3 by VIH method. The surface acidity was charactered by NH3-TPD and Py-FTIR was used to study the Al enviroment. And N2 adsorption desorption isotherms and XRD were used to characterize the four model catalysts. The results showed that the model catalyst’s pore size distribution kept unchanged and uniform compared with the former supports, and the surface properies similar to pure Al2O3. Key words: catalyst; preparation; characterization and evaluation 目 录 第1章 前 言 1 第2章 文献综述 2 2.1 模型催化剂的制备 2 2.1.