Review on the catalytic tri-reforming of methane - Part I: Impact of operating conditions, catalyst deactivation and regeneration

[Display omitted] •TRM is highly influenced by reaction temperature, pressure and feed composition.•Catalyst deactivation constitutes the principal issue of TRM.•Deactivated catalyst by solid carbon deposition could be regenerated by oxidation.•Deactivated catalyst by poisoning could be partially regenerated by oxidation.•Deactivated catalyst by thermal sintering still remains as a big challenge in TRM. Tri-reforming of methane (TRM) allows the production of syngas with a low environmental impact, an optimal energetic consumption, and a modular H2/CO molar ratio. However, despite a large number of publications devoted to TRM reaction, this process is still in its infancy and faces technical issues due to the catalyst deactivation by the formation of solid carbon, thermal sintering, vapor-solid reactions, and poisoning. Moreover, TRM reaction is also highly dependent on the operational conditions. This article provides a critical analysis of the last achievements on the TRM reaction. First, the thermodynamic, kinetic and mechanism aspects are presented and commented. Then, the impact of the operational conditions is analyzed. Finally, the main reasons of catalyst deactivation and the associated methods for catalyst regeneration are discussed. In parallel, catalytic efficiency is tentatively linked to physico-chemical properties of the catalyst, and recommendations are proposed for the future work on TRM process.