There is a gross imbalance for utilization of CO2 in that global demand is 80Mtpa, which is supplied from geological reservoirs, though anthropogenic sources exceed 18,000Mtpa. We often consider CO2 as a naturally occurring abundant gas, CO2 must be captured and purified before use and the energy and capital cost of collecting, concentrating and purifying CO2 is often neglected. Currently, current pricing of CO2 is on the order of $20/tonne, though natural supplies are getting closer to being exhausted. Once these supplies are depleted, CO2 will have to be captured from other sources. Cost projections for capture for direct air capture have been projected to be as high as $1,000/tonne, with some recent claims of $100/tonne, whereas capture from coal exhaust is projected to be $60/tonne. Regardless of source, the costs are due to the costly infrastructure (hundreds of millions of dollars) and the energy costs associated with intensive steps of regenerating a capture solvent (-85 kJ/mol) and compression (-12 kJ/mol). Thus, if any catalysis is performed on CO2, there is ~100 kJ/mol of energy already lost in purifying and compressing CO2 prior to any catalytic conversion. If the capture and catalytic conversion could be conjoined, the capital and energetic costs could be lessened. Further, catalytically converting CO2 captured in solution has many potential benefits including: faster reaction rates, catalysis at atmospheric (CO2) pressures, lower temperatures, different reactive pathways (carbonate VS CO2), all while being catalytic with respect to the capture solvent. We present here an integrated approach of combined capture and conversion of CO2 to methanol in the same solvent, demonstrating that carbon capture solvents are optimal solvents capture CO2 from dilute gas streams and also the optimal solvents for catalytic hydrogenations to methanol using either homogeneous and heterogeneous catalysts. This talk explores the chemical, energetic and processing synergies of capture and conversion and how this approach may open new frontiers in carbon capture, utilization and storage.

New frontiers in CCUS: Integrated capture and catalytic conversion of CO2

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.