蜂窝型整体结构催化剂浸渍过程动力学行为.pdfVIP

蜂窝型整体结构催化剂浸渍过程的动力学行为* 王寅, 赫崇衡, 汤睿, 冯大龙, 李平 （华东理工大学化学工程联合国家重点实验室，上海 200237 ） 摘要：以贵金属Pd( Ⅱ)和过渡金属Mn( Ⅱ)为活性组分，具γ-Al O 涂层的堇青石陶瓷蜂窝为载体，采用过量 2 3 浸渍法，考察了蜂窝型整体结构催化剂制备过程中浸渍条件（浸渍液 pH 值、温度和浓度）对活性组分在 载体上吸附量的影响，确定了Pd( Ⅱ)和Mn( Ⅱ)适宜的浸渍pH 值和温度。比较活性组分浸渍过程中的毛细 管渗透速率(τ)、扩散浸渍速率(τ )和吸附速率(τ) ，发现浸渍过程为吸附动力学控制。根据Lagergren 吸附 c d a 动力学模型拟合了活性组分在不同浓度下的吸附曲线，并以Langmuir 和Freundlich 吸附等温方程对吸附等 温线进行了拟合。结果表明，Lagergren 二阶吸附模型更吻合实际吸附行为；Pd( Ⅱ)和Mn( Ⅱ) 的吸附都遵循 Langmuir 单层吸附机制。 关键词：整体结构催化剂；浸渍；金属离子；吸附速率；吸附等温线 中图分类号：O 647 文献标识码：A Kinetic behavior of metal ion impregnation on monolithic support Wang Yin, He Chongheng, Tang Rui, Feng Dalong, Li Ping (State Key Laboratory of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China) Abstract ：The effects of impregnating conditions on the adsorption capacities of Pd( Ⅱ) and Mn( Ⅱ) over γ-alumina-coated cordierite honeycomb under excessive impregnation have been studied including pH, temperature and concentration of impregnating solution. The capillary permeation rate (τ), diffusion rate (τ ) and adsorption rate (τ) have been calculated respectively. c d a The results reveal that the impregnation of both Pd( Ⅱ) and Mn( Ⅱ) on the monolithic support are kinetic controlled process. The adsorption kinetic curves of different concentrations of impregnating solution have been simulated with both Lagergren first order and second order models. The results show that Lagergren second order model fits more properly than the first order