Waste CO2 capture and utilization for methanol production via a novel membrane contactor reactor process: Techno-economic analysis (TEA), and comparison with other existing and emerging technologies

Abstract

We introduced recently a CO2 capture and utilization (CCU) technology that produces methanol (MeOH), from waste CO2 employing a novel configuration combining a reverse water gas shift reactor (RWGSR) with a membrane contactor reactor for MeOH synthesis (MeS-MCR). The integrated RWGSR/MeS-MCR process overcomes the challenges direct CO2 conversion into MeOH faces and achieves carbon conversions exceeding 80 %, significantly surpassing the equilibrium conversion of ∼ 20–30 % for the MeS reaction. In this study, a techno-economic analysis (TEA) was conducted on the RWGSR/MeS-MCR process along with four other CO2-to-MeOH CCU processes. Key economic parameters, as well as the energy efficiency, were analyzed with respect to CO2 and renewable hydrogen (H2) costs and plant capacity. The study revealed that the RWGSR/MeS-MCR technology has the highest energy efficiency and the best economic performance among all the technologies investigated. All technologies offer the significant societal benefit of capturing and utilizing waste CO2, but under present CO2 and renewable H2 costs, they cannot currently compete cost-wise with conventional MeOH production methods. However, under a future scenario whereby government incentives lower the CO2 cost and technological advances decrease the price of renewable H2, the proposed RWGSR/MeS-MCR process and another catalytic technology (CAMERE) become price competitive.