CO2 To Carbon Monoxide Research Articles

The Research work of Dr. Ishida ‐ including Syntheses and Their Photocatalytic CO2 Reduction of Dinuclear Metal Complexes with Peptide Linkages project

The process of photosynthesis holds potential to be harnessed for addressing increasing CO2 levels, as well as for finding solutions for energy shortages resulting from depleted fossil fuel reserves. Professor Hitoshi Ishida, Laboratory on Functional Metal Complexes, Kansai University, has extensive expertise in creating artificial enzymes and is interested in developing techniques to emulate photosynthesis. The plan is to create a new photocatalyst by combining photochemical CO2 reduction catalytic reactions for artificial photosynthesis with the technology of functional molecule design using ‘peptide origami’, whereby proteins fold to form higher-order structures and exhibit functions. Ishida and his team are seeking to achieve artificial photosynthesis by using ruthenium complexes as catalysts in CO2 reduction reactions that can reduce CO2 to carbon monoxide (CO) and formic acid (HCOOH), which are useful as energy sources. Ishida has created functional molecules combining metal complexes with proteins, including artificial metalloproteins ‐ a type of protein containing a metal ion ‐ using synthetic bipyridyl amino acid 5Bpy. This focused on a rare transition metal called ruthenium as the ruthenium complexes the researchers are investigating have a selectivity for carbon monoxide and formic acid reduction products that change depending on the reaction conditions. The ultimate goal of Ishida’s work is to find a solution to the problem of pollution, while addressing the need for alternatives to fossil fuels.

Using waste CO2 to increase ethanol production from corn ethanol biorefineries: Techno-economic analysis

Sustainable conversion of carbon dioxide (CO2) to value-added chemicals or fuels shifts a linear “cradle to grave chemicals or fuels manufacturing model” to a circular carbon economy. A key consideration for CO2 utilization is the economic viability of converting specific CO2 sources based on scale, purity, etc. Among different CO2 sources, the corn dry mill ethanol plant with onsite waste CO2 upgrading is considered as a low hanging fruit strategy for implementing CO2 utilization with minimum requirements for gas purification. This study investigates the detailed techno-economic analysis of using a hybrid bio-electrochemical process to convert waste CO2 streams from corn dry mill facilities into ethanol and demonstrates the impact of CO2 utilization on the biorefinery economics. The bio-electrochemical CO2 conversion process combines water electrolysis to hydrogen (H2), electrolysis of CO2-to-carbon monoxide (CO), and gas fermentation to ethanol. With onsite CO2 conversion, total ethanol yield can be potentially improved by 45%. In this study, variations of H2:CO ratio ranging from 0 to 5 are explored to understand the impact of gas mixture composition on economic viability. The techno-economic analysis results show single-pass carbon yield in the biological conversion step can be potentially improved up to 100% when using H2 as an alternative energy source. Upgrading waste CO2 generated from a corn dry mill facility via biological CO2 to ethanol conversion is likely to be cost effective under the following conditions: high CO2 electrolysis energy efficiency (≥70% theoretical), low electricity cost (≤$0.02/kWh), and high CO2 electrolysis conversion efficiency (≥50% CO2 input).

Electroreduction of Carbon Dioxide to Syngas: From Concept to Pilot Plant

Increasing evidence suggests that the unwanted effects of climate change, including global warming, rising sea levels, and erratic weather patterns are the result of the increasing atmospheric concentrations of carbon dioxide and other greenhouse gasses. Further development and integration of renewable but intermittent energy sources such as solar and wind, as well as enhancing energy efficiency in buildings and transportation applications will be critical to significantly reduce global CO2 emissions. An alternative strategy to reduce CO2 emissions is to use CO2as a feedstock in the production of chemicals. The electrochemical reduction of CO2 into useful chemicals such as formic acid, carbon monoxide (CO), hydrocarbons, or alcohols has started to receive significant attention, both in academia and industry. Most research efforts over the last decade have focused on the development of increasingly better cathode catalyst for the efficient electrochemical reduction of CO2 to formic acid, CO, and other products. A few companies are trying to commercialize CO2 to formic acid, but the world market for formic acid is small. The bigger opportunities lie in conversion of CO2 to CO or syngas, as that product feds directly into the well-known Fischer-Tropsch for the production of chemical and fuels. Our group and others have advanced electrolysis of CO2to CO to the level where companies have started to look into scale up, including testing of the process in a pilot plant. This presentation will summarize the development of suitable cathode catalysts for selective CO2 to CO conversion, but also point out the importance of developing suitable gas diffusion electrodes (given that the CO2 feed is a gas), and the tuning of the electrolyte composition to maximize performance. Furthermore, this presentation will cover the importance of optimizing the anode side, typically the oxygen evolution reaction, in order to achieve much better energetic efficiencies. In parallel with these experimental efforts we have pursued a techno-economic analysis as well as a life-cycle analysis of electroreduction to different products, including the separation steps needed before and after, to identify the most important areas that will need improvement to enhance economic feasibility and to ensure and maximize net negative greenhouse gas emissions.