The intrinsic kinetics of CO₂ methanation over an industrial nickel-based catalyst was determined for a temperature range between 250 °C to 350 °C. The kinetic experiments were performed operating an integral fixed-bed reactor far from equilibrium conditions, in the absence of heat and mass resistances and at the atmospheric pressure. Five mechanistic-based models for describing the reaction kinetics were taken from literature and used for fitting the experimental reaction rates. Model discrimination was based on the assessment of the thermodynamic consistency and statistical significance of inherent parameters (for 95% confidence level). Comparison of the adequacy of fit between accepted models was done through the determination of the corresponding F-values to select the best model. The selected model assumes a formyl intermediate mechanism with a hydroxyl group being the most abundant species. The proposed reaction kinetics was further validated by the simulation of an isothermal plug-flow reactor operating at the same experimental conditions employed in this work, where a reasonable agreement between model predictions and the observed values was obtained.

确定了在250°C至350°C的温度范围内，工业镍基催化剂上CO ₂甲烷化的内在动力学。在没有热和质量阻力且在大气压下，在远离平衡条件的条件下操作整体固定床反应器进行了动力学实验。从文献中获得了五个用于描述反应动力学的基于机理的模型，并将其用于拟合实验反应速率。模型判别基于对热力学一致性和固有参数的统计显着性的评估（对于95％置信度）。通过确定相应的F，比较了接受模型之间的拟合是否足够值以选择最佳模型。选择的模型假定甲酰基中间机理，其中羟基是最丰富的物种。拟议的反应动力学进一步通过在该工作中采用的相同实验条件下运行的等温活塞流反应器的仿真进行了验证，其中在模型预测和观测值之间获得了合理的一致性。