Recycling carbon emissions with electrochemical reduction

What is it about?

Reducing carbon emissions has become a top priority to prevent the worst impacts of global warming. To limit the rise in global temperatures, various governing bodies have set a goal of achieving net-zero carbon emissions by 2050. To realize these goals, there have been various strategies to reduce the amount of carbon dioxide (CO₂) in the atmosphere. For example, in the transport and energy sectors, there has been a shift towards carbon-free alternatives, while various solutions have been developed to capture and store CO₂ emissions from industrial processes. This chapter presents the electrochemical reduction of CO₂ as an additional decarbonisation technique. In this process, electricity is used to drive a CO₂ reduction reaction (CO2RR) that converts CO₂ into important chemicals that would other-wise need to be derived from fossil fuels. In doing so, the method indirectly lowers CO₂ levels by reducing fossil fuel consumption.

Featured Image

Photo by Nikola Johnny Mirkovic on Unsplash

Photo by Nikola Johnny Mirkovic on Unsplash

Why is it important?

Some of the important products obtained from CO2RR include syngas (a mixture of carbon monoxide and hydrogen), formic acid, methanol, and ethylene. These chemicals are highly sought after due to their vast applicability as fuels or chemical substrates. For example, the global demand for methanol and ethylene sits at 100 million tons and 158 million tons, respectively. Despite its benefits, CO2RR requires additional purification and separation steps that add to the financial and energy cost of the operation. Along with improving the product selectivity and production rates, it is necessary to manage the large energy costs of carrying out the reaction. This can be achieved by improving catalyst and reactor designs and coupling the process to industries that have cleaner CO₂ streams. KEY TAKEAWAY: CO2RR is an attractive potential solution to mitigate carbon emissions on our planet. However, various operational limitations need to be over-come before this technology can be practically realized and become financially feasible.