Poster Z4 - Conversion of CO2 as CaCO3 Nano-Particles Using Amino Acids

Friday, October 25, 2024

3:30 PM – 4:30 PM EST

Location: Exhibit Hall E, F & G

Presenting Author(s)

QINGYANG LI, MS (he/him/his)

Research Assisstant
west virginia university, West Virginia, United States

Primary Investigator(s)

Bingyun Li, PhD (he/him/his)

Professor
West Virginia University School of Medicine, United States

Introduction: Carbon dioxide (CO2) is the most significant greenhouse gas (GHG) exacerbating global warming. This warming trend threatens to unleash various environmental crises, including severe weather events, disruption of ecosystems, and rising sea levels. Nano-CaCO3 have been widely investigated for diverse biomedical applications including diagnosis, treatment, and theranostics due to their excellent biocompatibility/biodegradability and pH-sensitive properties, as well as their ease of modification1, 2. Developing an effective, efficient, economical, and environmentally-friendly (4E) method to convert CO2 to value-added nano-CaCO3 seems to be an attractive strategy to offset the overall cost for CO2 management.

Materials and

Methods: The solvents for CO2 conversion were prepared by dissolving defined amounts of a base and/or an amino acid at a certain molar ratio and mixing in plastic centrifuge tubes. A serological pipette was positioned at the base of each tube to serve as a CO2 gas outlet. A mass flow controller was used to regulate the CO2 flow rate. After certain time of CO2 bubbling, CaCl2 was added and the solvent was vortexed briefly to mix. Then precipitates were collected by centrifugation and washed with deionized water (Fig. 1).

Results, Conclusions, and Discussions: X-ray diffraction (XRD) spectra of the solid products found that the products were pure calcite, the most stable phase of CaCO3. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations showed that the CaCO3 had an average diameter of approximately 70 nm (Fig. 1). In addition, the morphology of CaCO3 changed with the amino acid species and the dosage. Compared with the solvent without amino acid, it was found that amino acid plays an important role in producing nano-CaCO3. Nuclear magnetic resonance (NMR) data indicated that protonated amino acid reacted with CO2 to form carbamate first, and then carbamate was hydrolyzed into bicarbonate which reacted further with Ca2+ to form nano-CaCO3.
For the first time, we developed an innovative method based on amino acid salt solvents to convert CO2 into nano-CaCO3. The production of nano-CaCO3 from CO2 is significant, because it not only converts CO2 to minerals that are stable but the nano-minerals also have broad applications across various industries. According to reports by Grand View Research3 and Market Research Community4, the global CaCO3 nano-minerals market was valued at US$ 8.4 billion in 2022, and would reach more than US$ 17 billion in 2023.

Acknowledgements (Optional): This material is based upon work supported by the Agriculture and Food Research Initiative Competitive Grant (no. 2020-68012-31881) from the USDA National Institute of Food and Agriculture and by the WV Higher Education Policy Commission under grant number RCG23-12 and the WVU Internal Grant. We also acknowledge use of the WVU Shared Research Facilities.