Combined capture and reduction of CO2 to methanol using a dual-bed packed reactor

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2023-08, Vol.470, p.144227, Article 144227
• Main Authors: Wirner, Luca C., Kosaka, Fumihiko, Sasayama, Tomone, Liu, Yanyong, Urakawa, Atsushi, Kuramoto, Koji
• Format: Article
• Language: English
• Subjects: CO2 capture; CO2 hydrogenation; CO2 utilization; Methanol synthesis
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2023.144227

•A combined CO2 capture and reduction process to methanol was developed and tested.•Addition of Na/Al2O3 increased CCR performance to methanol.•A sequential configuration of Na/Al2O3 with Cu/ZnO/Al2O3 was optimal.•Higher pressures increased CO2 capture performance and methanol selectivity. Recently, carbon capture and reduction (CCR) technology has gained interest to directly convert CO2 to value-added products without requiring purification of CO2 and its subsequent transportation. CCR to methanol in one dual function material (DFM) poses mechanistic and kinetic challenges. To counteract this, a process combining Na/Al2O3 as a capture component and Cu/ZnO/Al2O3 (CZA) as methanol synthesis catalyst was developed to allow CCR to methanol. With a 5 vol% CO2 flow for capture and subsequent H2 stream combined with a temperature swing, a methanol selectivity of 26 % was achieved at 9 bar. Further investigation found that Na/Al2O3 significantly increased methanol yield, while a stacked configuration of Na/Al2O3 followed by CZA significantly outperformed a mixed configuration of the two catalysts. With further investigation of operation at higher pressure and surface mechanism, an effective CCR to methanol process using two affordable yet readily available catalysts can be realized.