Plants that grow in the ground make all their carbon-based infrastructure from carbon dioxide (CO2). By contrast, plants built by chemists use petroleum and natural gas as their carbon feedstock. In a review, De Luna et al. explore the prospective challenges and opportunities for manufacturing commodity chemicals such as ethylene and alcohols by direct electrochemical reduction of CO2. They estimate that production costs would be competitive with fossil technologies if renewable electricity costs drop below 4 cents per kilowatt-hour and electrical-to-chemical conversion efficiencies reach 60%. As the world continues to transition toward carbon emissions–free energy technologies, there remains a need to also reduce the carbon emissions of the chemical production industry. Today many of the world's chemicals are produced from fossil fuel–derived feedstocks. Electrochemical conversion of carbon dioxide (CO2) into chemical feedstocks offers a way to turn waste emissions into valuable products, closing the carbon loop. When coupled to renewable sources of electricity, these products can be made with a net negative carbon emissions footprint, helping to sequester CO2 into usable goods. Research and development into electrocatalytic materials for CO2 reduction has intensified in recent years, with advances in selectivity, efficiency, and reaction rate progressing toward practical implementation. A variety of chemical products can be made from CO2, such as alcohols, oxygenates, synthesis gas (syngas), and olefins--staples in the global chemical industry. Because these products are produced at substantial scale, a switch to renewably powered production could result in a substantial carbon emissions reduction impact. The advancement of electrochemical technology to convert electrons generated from renewable power into stable chemical form also represents one avenue to long-term (e.g., seasonal) storage of energy. The science of electrocatalytic CO2 reduction continues to progress, with priority given to the need to pinpoint more accurately the targets for practical application, the economics of chemical products, and barriers to market entry.
Apr-26-2019, 15:51:09 GMT