Evaluation of a Carbonic Anhydrase Mimic for Industrial Carbon Capture

• Published in: Environmental science & technology Vol. 47; no. 17; pp. 10049 - 10055
• Main Authors: Floyd, William C, Baker, Sarah E, Valdez, Carlos A, Stolaroff, Joshuah K, Bearinger, Jane P, Satcher, Joe H, Aines, Roger D
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 03-09-2013
• Subjects: Acidity; Carbon sequestration; Carbonates - chemistry; Carbonic Anhydrases - chemistry; Catalysis; Catalysts; Climatology. Bioclimatology. Climate change; Earth, ocean, space; Environmental Restoration and Remediation - methods; Exact sciences and technology; External geophysics; Heterocyclic Compounds - chemistry; Hydrogen-Ion Concentration; Meteorology; Molecules; Perchlorates - chemistry; Potassium - chemistry; Temperature; Zinc; Zinc Compounds - chemistry; Gas absorption; Gas liquid; Zinc complex; Carbon dioxide; Organic ligand; CO2 sequestration; Oxygen heterocycle; Carbon sequestration; greenhouse gas; Macrocycle; sustainable development; Mitigation; Physicochemical purification; Flue gas purification; Catalyst; climate change
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es401336f

Zinc(II) cyclen, a small molecule mimic of the enzyme carbonic anhydrase, was evaluated under rigorous conditions resembling those in an industrial carbon capture process: high pH (>12), nearly saturated salt concentrations (45% K2CO3) and elevated temperatures (100–130 °C). We found that the catalytic activity of zinc cyclen increased with increasing temperature and pH and was retained after exposure to a 45% w/w K2CO3 solution at 130 °C for 6 days. However, high bicarbonate concentrations markedly reduced the activity of the catalyst. Our results establish a benchmark level of stability and provide qualitative insights for the design of improved small-molecule carbon capture catalysts.