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

摘要： 针对矿物燃料燃烧所产生的二氧化硫气体的污染问题，进行了负载于氧化铝上的硫酸镍催化H₂还原SO₂反应的动力学研究。在固定床流动积分反应器中考察了反应温度、空速及反应物中H₂与SO₂配比对反应速度的影响。动力学的实验条件：温度范围为370～450℃，反应混合气的流速为8000mL/h，反应物中H₂与SO₂的比例为0.5～2.0。通过数值积分方法进行拟合，发现反应的积分动力学方程较好的符合
r_SO2= Kp_H2b_SO2p_SO2/[ 1+b_SO2p_SO2+b_H2Op_H2O+(b_S2p_S2)^1/2].
即典型的存在产物吸附阻碍的R-E方程。这一结果与本实验室对该催化剂表征所发现的H₂在催化剂上无明显吸附，而H₂O，S₂，SO₂明显吸附相一致。

关键词: 催化还原, 动力学, 二氧化硫, 氢, 硫酸镍