【摘要】 近十几年来,用脉冲-应答技术测定催化剂的传递和吸附系数,受到了广泛的注意.在这种测量技术中,对应答峰的分析方法已提出5～6种之多.其中,富里埃分析法是比较准确的方法之一.研究中采用富里埃分析法求取了固定床反应器中多孔催化剂的三种传递系数(轴向扩散系数E、膜扩散系数K_f、粒内有效扩散系数D_e)和两种吸附系数(吸附平衡常数K_a和吸附速率常数K_a),并对所得的结果进行了灵敏度分析.实验结果说明了这一方法的优点.此外,还探讨了目标函数和周期的选取对测量的影响.对各参数灵敏度考察的结果:在低速区,K_a和k_f最灵敏,D_e次之,E和k_a的灵敏度很低;在高速区,所得结果与文献报道一致(K_a和D_e最灵敏,E次之,k_f和K_a的灵敏度很低).更多还原

【Abstract】 For more than ten year,extensive attention has been paid to the impulseresponse teachnique for determinning the transfer and adsorption coefficients of catalyst.In this technique,five or six analytical methods of response peaks have been proposed,among which Fourier analysis is the relatively accurate one.In this work,three transfer coefficients(axial dispersion coefficient,E,film mass transfer coefficient,k_f,and effective interparticle diffusivity,D_c)and two adsorption coefficients(adsorption equilibrium constant,K_a and adsorption rate constant,K_a) of porous catalyst in fixed-bed reactors are obtained by Fourier analysis.The sensitivities of the results obtained are discussed and the advantages of Fourier analysis are mentioned.In addition,the influence of the objective function and the period for measurement are also explored.The experimental results show:in the low velocity region,the order of sensitivities is K_a and k_f>D_e>E and k_a;in the high velocity region,the sensitivities are consistent with those in literatures(K_a and D_e>E>K_a and k_f).更多还原