不同表面吸附中心上微分吸附热曲线的模拟  

Simulation of the Microcalorimetric Adsorption Curves for Different Surface Sites

作　　者：雷艳华[1] 葛欣[1] 李明时[1] 沈俭一[1] 

机构地区：[1]南京大学化学系,南京210093

出　　处：《南京大学学报（自然科学版）》2002年第1期124-130,共7页Journal of Nanjing University（Natural Science）

基　　金：国家自然科学基金 (2 99730 13);国家重点基础研究发展规划项目 (G19990 2 2 40 8)

摘　　要：考察了一种气体吸附质同时在多种吸附中心上吸附时的吸附热和吸附量 ,在固体催化剂由两种吸附中心组成且均为Langmuir理想吸附的情况下 ,讨论了气体在固体催化剂表面吸附的微分吸附热随表面覆盖度变化的各种可能形状 ,并模拟了乙烯在Pt/SiO2The heat and uptake for an adsorbate adsorbed on several different adsorption sites have been studied by a phenomenological simulation method. For the special case that there are two different Langmuir adsorption sites in a catalyst, various shapes that may be possibly formed for the heat versus coverage curves have been discussed. Finally, the heat versus coverage curve obtained experimentally for the adsorption of ethylene on a Pt/SiO 2 catalyst was successfully simulated by the method. Additional information in terms of the ratio of equilibrium constants and the difference of surface entropies for the adsorbate on the different adsorption sites can be obtained accordingly.

关 键 词：固体表面 吸附热 微分吸附热曲线 模拟 吸附量 气体吸附质 表面覆盖度 催化剂 

分 类 号：O647.3[理学—物理化学] O643.3[理学—化学]