Methanol from Catalytic Conversion of Biogas-Based Syngas (CO, H2)

Hydrogen (H2) will foster the decarbonization roadmap. H2 faces challenges that hamper its application, storage and transport being the major issues needing reliable and affordable solutions. Its transformation into H2-based green methanol offers a potential alternative. The present research applied a multi-step inter-cooled fixed-bed reactor using a Cu/ZnO/Al2O3 catalyst and fed with biogas-derived syngas of different CO/H2 concentration ratios. The reaction is mainly carried out at 503 K and 5 MPa. Conversions and yields were measured after each of the 4 steps and revealed a total conversion of 97.8%. The catalyst was fully characterized and showed a nano-size structural cell with ultrafine crystallinity. Aspen simulation predictions using the Graaf et al. kinetic expressions accurately fitted the experimental results. The methanol purity exceeded 99.5%. The concept can be readily scaled up by using 3 successive catalytic beds with intercooling. Pilot-plant experiments will be further used to enhance the Technology Readiness Level.