US Investigates Beneficial Uses of CO2

The need to reduce greenhouse gases is becoming ever more important and many countries are working towards programs for capturing and storing the CO₂ emitted by heavy industries and power generation. The CO₂ either needs to be sequestered into permanent, safe storage or, alternatively, used as a resource.

CO₂ is a stable compound with a low energy state and does not readily participate in chemical reactions without added energy. Additionally, the supply of CO₂ far exceeds the current demand. Identifying economically feasible approaches that utilize large amounts of CO₂ as a feedstock is very challenging.

The United States Department of Energy (DOE), through its National Energy Technology Laboratory (NETL), has an active carbon sequestration program. One area of development is CO₂ Utilization Focus Area, which aims to identify and develop a suite of technologies that can beneficially use CO₂ to produce useful products that can generate revenue to offset capture costs associated with Carbon Dioxide Capture and Storage (CCS) implementation, contribute to CO₂ emissions reductions, and reduce the demand for petroleum-based feedstocks and products. Darin Damiani, NETL, and colleagues summarize the current status of CO₂ use in the USA:

Enhanced hydrocarbon recovery shows great promise for both increasing energy supply and storing large volumes of CO₂. CO₂-enhanced oil recovery and CO₂-enhanced gas recovery are techniques in which compressed CO₂ is injected into depleted oil and gas fields to increase production.
Chemicals production: advances in catalysts and alternative reactive pathways may make it feasible to use CO₂ as a feedstock in the production of bulk chemicals. DOE supported research efforts include evaluating the potential to expand existing markets and identifying substitutes for petroleum-derived feedstocks.
Mineralization processes that use CO₂ to cure concrete and to create inorganic binders as an alternative to Portland cement show promise for consuming CO₂ and reducing energy intensity. Concrete is one of the most widely used construction materials, and the concrete industry is among the largest producers of CO₂ emissions.
Plastics and polymer production: The production of stable plastics through copolymerization to produce polycarbonates using CO₂ requires less energy by eliminating the need for intermediate reactions. Advances in this area have led to at least one process that is approaching commercialization.