Carbon Dioxide Reforming of Methane

Thermodynamic and kinetic aspects of the carbon dioxide reforming of methane are considered. Data on the types of catalytic systems used and on specific features of the commercial implementation of the process are systematized. The optimum temperature and pressure ranges for the carbon dioxide reforming of methane are 700–900°C and 2–4 MPa, respectively. Detailed analysis of the published data on the activity and stability of dry reforming catalysts shows that the key factor influencing the activity of the catalysts and their resistance to coking is the balance between the properties of the support and composition of the active metal phase. For example, the acid–base properties of the support determine the strength of binding of the metal with the surface, which can influence both the catalyst activity and its stability by preventing sintering of the active component particles. The most widely supports are silicon and aluminum oxides and zirconium and titanium silicates. Their acidity is controlled by introducing doping additives such as cerium, calcium, and magnesium oxides. Both base transition (Ni and Co) and noble (Rh, Ru, Pd, Pt, and Ir) metals as well as bimetallic systems containing sites of both types can serve as an active phase. The main problem restricting the practical use and scaling of the carbon dioxide reforming of methane is catalyst deactivation due to support coking and sintering of the active component particles.