Carbon capture and utilization (CCU) technologies capture CO₂ from industrial sources or ambient air and use the captured CO₂ as a carbon source for value-added products such as chemicals. To evaluate the potential impact of CCU technologies on chemical industry greenhouse gas (GHG) emissions, researchers developed a bottom-up model of global production of 20 major bulk chemicals, which are collectively responsible for more than three-quarters of the industry’s GHG emissions.

According to the model, production of these chemicals in 2030 using CCU technologies would substantially increase mass flows compared with conventional technologies, due to the large amounts of CO₂ used and wastewater produced.

CCU-based production would also require at least 18.1 PWh of electricity, corresponding to more than half of the projected global electricity production in 2030. Thus, achieving substantial GHG emissions reductions from CCU technologies would require a massive expansion of low-carbon electricity generation.

In the scenario with the lowest GHG emissions, conventional production would be replaced by CCU, including technologies that are currently in early stages of research and development, with all electricity inputs supplied by wind power.

According to the authors, in such a scenario, annual GHG emissions would decrease by 3.5 Gt CO₂-eq, potentially rendering the chemical industry nearly carbon-neutral and independent of fossil resources. 

https://www.pnas.org/content/early/2019/05/07/1821029116