The chemical industry faces a unique challenge in order to comply with countries’ commitments to become carbon-neutral. In Switzerland, where the Federal Council has announced its commitment to carbon-neutrality by 2050, the chemical industry is contemplating how it can go about reaching this goal when many of the raw materials it uses contain carbon.
"Polymers, plastics, synthetic textile fibers, and medicines all contain carbon. It has to come from somewhere," explains Marco Mazzotti, Professor of Process Engineering at ETH Zurich. The chemical industry currently procures most of its carbon from oil and natural gas, meaning that when chemical products are burned or decompose, they release carbon dioxide.
Mazzotti is part of a team of researchers from ETH Zurich and Utrecht University that is investigating carbon-neutral alternatives within the chemical industry. Using methanol production as a case study, the team determined that it is in fact possible to reach net-zero carbon dioxide emissions, but this transition won’t come without certain costs, as the authors explain in their study.
In a quantitative comparative assessment of three technology chains that enable a carbon-neutral chemical industry, the authors write, “These are based (i) on the use of fossil fuels and current chemical processes and infrastructure coupled with carbon capture and storage (CCS route), (ii) on the use of captured CO2 as a feedstock together with “green” hydrogen in new chemical processes (CCU route), (iii) on the use of biomass grown and processed for the specific purpose of making chemicals (BIO route).” The study explains explicitly the distinct advantages and disadvantages of each route.
For example, the CCU route consumes 10 to 25 times more electricity than the CCS and BIO routes. Meanwhile, the BIO route needs 40 and 400 times more land capacity, than that needed by the CCU and CCS routes, respectively. On the other hand, CO2 emissions of the CCU route grow about 8 to 10 times faster than that of the CCS and BIO routes.
While the conclusions from this study do not necessarily offer clear direction, they do show that there are several directions that the chemical industry could take, all of which lead to a carbon-neutral future.