Intrinsic Kinetics of CO Methanation over ZrO₂/Al₂O₃ Supported Ni-Based Catalyst

CO methanation reaction over Ni-based complex-support catalyst for synthetic natural gas production was systematically investigated in a fixed-bed reactor.The influence of operating conditions on the methanation reaction was explored at reaction temperature of 250~440℃,pressure of 0.1~2.5 MPa and n_H2/n_CO of 1.0~4.5.The experimental results indicated that the conversion of CO and selectivity of CH₄ increased with the increase of reaction temperature and pressure.The highest conversion of CO was achieved at 340℃.When n_H2/n_CO=3.0,a relatively high conversion of CO and high selectivity of CH₄ were obtained.The experimental data of intrinsic kinetics of CO methanantion over Ni-based catalyst were measured by orthogonal experiments.Hyperbolic type kinetic models were developed in terms of the reaction rates of CO₂ and CH₄ in form of the fugacity of the reactants.The parameters of the models were obtained through max inherit optimization.It was proved by residual analysis and statistical test that the kinetic models are reliable and acceptable.