Semester
Summer
Date of Graduation
2025
Document Type
Dissertation
Degree Type
PhD
College
Statler College of Engineering and Mineral Resources
Department
Chemical and Biomedical Engineering
Committee Co-Chair
Bingyun Li; Margaret Bennewitz
Committee Member
Wenyuan Li
Committee Member
Soumya Srivastava
Committee Member
Todd Stueckle
Abstract
The current global situation concerning CO2 emissions is increasingly alarming, with rising concentrations of CO2 significantly worsening climate change and global warming. Atmospheric CO2 levels are now at their highest in millions of years, driving a host of catastrophic effects, including but not limited to extreme weather events, rising sea levels, ocean acidification, disrupted ecosystems, deteriorating air quality, respiratory health issues, heat-related illnesses, threats to food and water security, and escalating social and geopolitical tensions. To keep global warming to no more than 1.5°C higher than that of pre-industry – as called for in the Paris Agreement – emissions need to be reduced by 45% by 2030 and reach net zero by 2050. In addition, The National Academy of Sciences has estimated that meeting the Paris Agreement’s goals will require scaling up to 10 gigatons (Gt) of carbon dioxide removal annually by 2050, with 20 Gt of carbon dioxide removal each year by 2100. Hence, CO2 management has become an urgent and inevitable event. An amino acid-driven method, characterized by stability, low volatility, and environmental friendliness, was introduced to capture and convert CO2 into various value-added nano-carbonates (e.g., CaCO3, BaCO3, Ag2CO3). These nano-carbonates are widely or potentially applied as fillers, medicines, and catalysts in various sectors including the industrial (e.g., food, construction, paint, polymer), biomedical, environmental, and electronic fields. The method can be two steps, or it can be simplified to one step when the hydroxide has relatively high solubility and its corresponding carbonate has low solubility. For two steps: 1) CO2 is bubbled into an amino acid salt solvent (dissolving hydroxide and amino acid); 2) metal ions are added to mineralize captured CO2 into nano-carbonates. It has been verified that our two-step method is universal, as nano-CaCO3, nano BaCO3 and nano-Ag2CO3 with size smaller than 100 nm have been successfully produced. For one step: 1) CO2 is bubbled into an amino acid salt solvent (dissolving hydroxide and amino acid) to produce nano-carbonate. Here, solvents were produced by dissolving barium hydroxide and amino acids, and the nano-BaCO3 was formed after bubbling CO2. Our method has shown that amino acids can be reused without any further purification. The morphology of nano-carbonates produced by these two methods can be tuned by using different amino acid concentrations and identities. The mechanism was determined that the amino acid plays a key role in controlling the morphology of nano-carbonate. To evaluate the potential adaptation and viability of our method in different industries with different CO2 concentrations (e.g., coal-fired power plants: ~12-15%; natural gas turbines: ~ 3-5%; cement plants: ~20-25%), flue gas with different CO2 concentrations (4%, 12%, and 20%) was utilized and evaluated. It was found that our system successfully captured and converted CO2 from these flue gases to nano CaCO3. Our study demonstrated that the amount of carbamate is a crucial factor in the formation of nano-scale particles, and it is positively correlated with the proportion of nanoparticles produced. Our method was also proven to be tunable for different flue gases, and the tuning methods are also discussed. In summary, we have developed a method using amino acid salt to convert CO2 to various stable nano-carbonates. This method is capable of converting CO2 from different flue gases, which will reduce CO2 emissions into the atmosphere and will reduce climate change. In addition, this invention is 4E (effective, efficient, economic, and environmentally friendly), which has the potential for commercialization.
Recommended Citation
Li, Qingyang, "Engineering Nanomaterials from Phase-change Biological Materials Reacting with Carbon Dioxide" (2025). Graduate Theses, Dissertations, and Problem Reports. 12968.
https://researchrepository.wvu.edu/etd/12968