Electrochemical carbon dioxide conversion for decarbonizing chemical production
| Author(s) | Shin, Haeun | |
| Date Accessioned | 2023-10-09T17:50:12Z | |
| Date Available | 2023-10-09T17:50:12Z | |
| Publication Date | 2023 | |
| SWORD Update | 2023-09-20T19:16:59Z | |
| Abstract | Decarbonizing a chemical and energy sector is a crucial task to address greenhouse gas emissions and to establish sustainable global economy. One promising approach to achieve this goal is through electrification of chemical production using carbon dioxide electroreduction (eCO2RR) as an important component of carbon capture and utilization (CCU) technologies. By converting captured CO2 to valuable chemicals, it leads to a substantial reduction in carbon emissions by utilizing CO2 as a feedstock. Moreover, eCO2RR enables the creation of new value chains within the CCU technology by transforming CO2 into products. In this work, I address the remaining challenges and present my research efforts aimed at advancing eCO2RR. ☐ In this thesis, I examine various approaches for effective utilization of eCO2RR as a sustainable pathway for decarbonizing chemical production. The thesis begins with a techno-economic analysis of low-temperature eCO2RR targeting the production of carbon monoxide, formic acid, ethylene and ethanol. This analysis incorporates the state-of-the-art performances and corresponding production costs in terms of US dollars per kg of product including capital and operating costs of electrolyzer and separation units. To accurately capture the relationship between current and voltage, a newly developed voltammetric model is introduced. In addition, it also provides a research guideline to enhance the economic viability of eCO2RR proposing benchmark values for key parameters such as selectivity, stability, single-pass conversion and electrolyzer configuration for each targeted product. ☐ Motivated by the previous study, I present a mechanism for determining the selectivity of C2 products (ethylene, ethanol, and acetate) in eCO2RR on copper catalysts. By investigating the effects of different catalyst roughness factors and electrolyte pH, the study reveals that the selectivity of C2 products on copper is predominantly influenced by the local mass transport diffusion properties of the key intermediate, ketene and its reaction with hydroxide ion. This work demonstrates the ability to achieve a wide range of acetate selectivity, ranging from 30 to 60% by controlling the reaction conditions and catalyst properties. In collaboration with theoretical calculations, the proposed mechanism provides insights into the factors that can be engineered to steer the selectivity towards desired C2 products. ☐ Lastly, I discuss a potential opportunity of a hybrid electro-biochemical system as a building block of chemicals and food. Motivated by recent advancements in acetate production through eCO2RR, this chapter investigates the potential for upgrading electrochemically synthesized acetate through integrating with microorganism-mediated fermentation processes. It discusses optimizing the eCO2RR systems to facilitate seamless integration, including reactor and catalyst designs to enable efficient production. By coupling electrochemical production with microbial conversion, it will highlight the potential for broad-spectrum CO2 utilization by creating new avenues for the production of a wide range of chemicals and food of interest. ☐ In Summary, this dissertation explores diverse approaches to enhance the effectiveness of eCO2RR and to create new opportunities in the pursuit of reducing CO2 emissions and building a sustainable planet for current and future generations. | |
| Advisor | Jiao, Feng | |
| Degree | Ph.D. | |
| Department | University of Delaware, Department of Chemical and Biomolecular Engineering | |
| DOI | https://doi.org/10.58088/xr34-hc14 | |
| Unique Identifier | 1417068810 | |
| URL | https://udspace.udel.edu/handle/19716/33493 | |
| Language | en | |
| Publisher | University of Delaware | |
| URI | https://login.udel.idm.oclc.org/login?url=https://www.proquest.com/dissertations-theses/electrochemical-carbon-dioxide-conversion/docview/2866770172/se-2?accountid=10457 | |
| Keywords | Greenhouse gas | |
| Keywords | Chemical production | |
| Keywords | Electrochemistry | |
| Keywords | Carbon dioxide electroreduction | |
| Keywords | Carbon dioxide conversion | |
| Title | Electrochemical carbon dioxide conversion for decarbonizing chemical production | |
| Type | Thesis |