Integrated process and solvent design using COSMO-RS for the production of CO from CO2 and H2

Abstract

Fluctuating H2 from renewable energy can be integrated into the chemical value chain by conversion of CO2 to CO via chemical storage. An efficient process combines the right chemical storage molecule in an optimized flowsheet with tailored solvents. For the resulting integrated process and solvent design problem, we present a hybrid stochastic-deterministic optimization approach combining computer-aided molecular design based on COSMO-RS and pinch-based process models for reactions and separations. Thereby, we are able to explore a large molecular design space and find optimal solvents for CO production based on a sound process-level design target. The optimization approach is shown to be both efficient and effective by designing novel solvents which improve process performance by more than 12% compared to a massive database screening of over 80,000 combinations of solvents and structural process variants.