论文部分内容阅读
本文以H_2在Cu/ZnO/Al_2O_3型低变催化剂上的程序升温脱附为例,解析了其TPD谱图。提出了T_f法及曲线拟合法。与其它几种方法计算结果的对比表明,该方法具一定的可靠性及可行性。由分析计算得到的动力学参数可知,同一催化剂,不同的活泼部位具有相同形式的脱附动力学方程,而只是动力学参数不同。计算结果还表明,Cu/ZnO/Al_2O_3型低变催化剂对H_2的有效表面为非理想表面,并求出脱附过程中的频率因子γ_d、活化能E_d与表面覆盖度θ的函数关系分别为指数函数和对函数。从脱附级数推测出,H_2在Cu/ZnO/Al_2O_3型低变催化剂上的吸附为分解二位吸附。
In this paper, the temperature-programmed desorption of H_2 on Cu / ZnO / Al_2O_3 catalysts was used as an example to analyze the TPD spectra. Proposed T_f method and curve fitting method. The comparison with other methods shows that the method has certain reliability and feasibility. From the kinetic parameters analyzed and calculated, we can see that the same catalyst, different active sites have the same form of desorption kinetics equation, but different kinetic parameters. The calculated results also show that the effective surface of H 2 Cu / ZnO / Al_2O_3 catalyst is non-ideal surface, and the frequency factor γ_d in desorption process is obtained. The function relationship between activation energy E_d and surface coverage θ are respectively exponential Function and function. It is inferred from the desorption series that the adsorption of H 2 on the Cu / ZnO / Al 2 O 3 low-shift catalyst is two-position decomposition.