A consecutive methanation scheme for conversion of CO2 – A study on Ni3Fe catalyst in a short-contact time micro packed bed reactor

Abstract

In this work, the kinetics of CO2 methanation reaction is investigated on a 17 wt% Ni3Fe/ɣ-Al2O3 catalyst under technical operation conditions of Power-to-Gas processes. A short-contact time microstructured packed bed reactor with internal cross-flow cooling channel was designed particularly for kinetic studies of the highly exothermic methanation reaction. The influence of temperature, pressure, reactant and product composition as well as residence time on the product composition and conversion of the reactants was carefully studied. In total more than 160 data points were collected and fitted to three literature models applying a non-isothermal reactor model. Based on the state-of-the-art kinetic models and the experimental observations, a new LHHW rate equation for the consecutive CO2 methanation reaction was developed. This new model has reasonably lower number of parameters and improves description of the reaction compared to literature models with regard to the Ni3Fe catalyst system. Special attention was paid to the selectivity behavior and the influence of carbon monoxide and water on the reaction.