关键词: 催化还原, 动力学, 二氧化硫, 氢, 硫酸镍

Abstract: The catalytic reduction of SO₂ by H₂ on NiSO₄/γ-Al₂O₃ has been investigated in detail in our Lab. In this paper we focused on the kinetics of this reaction. The experiments were carried out a packed flow glass in tegral reactor. The catalyst of 20～40 mesh NiSO₄/γ-Al₂O₃ was prepared by the method of impregnation, which was then calcined in air at 500℃ for 4 hours. NiSO₄/γ-Al₂O₃=3/10 (g/g). Isothermal experiments were carried out at t=370～430℃，the ratio of SO₂ to H₂ was 0.5～2.0，the inlet flow rate was 8000mL/h. With the method of orthogonal design and numerical integration, we got the reasonable mechanism kinetic equation as follows, r_SO2= Kp_H2b_SO2p_SO2/[ 1+b_SO2p_SO2+b_H2Op_H2O+(b_S2p_S2)^1/2]. This equation take a good agreement with the experiments. The adsorption and desorption experiments demonstrated that all reactants and products adsorbed on the surface of the catalyst except H₂. This result together with the kinetic equation make it clear that the mechanism of this reaction is R-E.

Key words: catalytic reduction, kinetics, SO₂, H₂, NiSO₄