Sorption enhanced carbon dioxide hydrogenation to methanol: Process design and optimization

Sorption enhanced synthesis has been previously shown to improve carbon dioxide hydrogenation to methanol by mitigating the thermodynamic limitations. This work investigates the efficiency of methanol synthesis via sorption enhanced carbon dioxide hydrogenation focusing on determining the optimal process parameters. The study is based upon a fully dynamic experimentally validated model of the process which is extended to account for adsorbent regeneration, downstream product separation and recirculation of the unreacted gases. An additional reactor configuration with a guard adsorbent layer is proposed for production of high purity methanol product. A multi-objective optimization study is performed to investigate the tradeoff between methanol production rate and product purity. The obtained results indicate that for synthesis of high purity methanol product, the optimal values of reactor temperature and catalyst mass fraction in the bed are 215 °C/0.65 and 235 °C/0.50 for the adiabatic and quasi-isothermal reactors, respectively.