Cycloaddition of Biogas-Contained CO₂ into Epoxides via Ionic Polymer Catalysis: An Experimental and Process Simulation Study

Abstract

Biogas upgrading technologies are crucial for the production of high-purity biomethane. Efficient CO 2 removal methods that are currently commercialized rely on "catch-and-release" mechanisms, and the CO 2 stream is usually discharged into the atmosphere without further utilization. From the standpoint of process sustainability, it would be advantageous to transform the CO 2 in biogas streams into value-added products. Herein, we propose the cycloaddition of CO 2 into epoxides as a biogas upgrader. Fed by propylene oxide (PO) and biogas with typical CO 2 concentration, or CO 2 separated from biogas following upgrading, reactions were conducted under optimal conditions using an ionic polymer as the catalyst. Based on the obtained PO conversions, process simulations were performed for the large-scale production of propylene carbonate (PC) using CO 2 separated from biogas. The PC yield was improved to 99.9% by process optimizations and reactant recycling at a molar flow rate of 100 kmol/h, which was shown to be commercially viable.

A Semi‐Serendipitous Journey towards the Commercialisation of a Catalytic Hydrocracking Process for Polymer Waste

“…Long before we considered working on plastic waste, the group was active in the field of sustainable chemistry, developing new catalysts that transform biomass (bio-polymers) and CO 2 into useful chemicals. With CO 2 , these transformations can be achieved either by combining CO 2 with a reactive coupling partner to encompass CO 2 into an organic (or inorganic) molecule without altering its oxidation state, [9,10] or it can be directly reduced into a variety of molecules (formic acid, [11] methanol, [12] methane, [13] ethylene, [14] etc.). Producing small molecules from CO 2 has a threefold interest as circular transportation fuels, in renewable hydrogen storage/utilisation as well as affording sustainable synthons for the chemical industry.…”