Following heterogeneous nucleation of CO₂ on H₂O ice nanoparticles with microsecond resolution

Journal Article · Tue Dec 01 00:00:00 EST 2015 · RSC Advances

DOI:https://doi.org/10.1039/c5ra19782a· OSTI ID:1238294

Tanimura, Shinobu ^[1]; Park, Yensil ^[1]; Amaya, Andrew ^[1]; Modak, Viraj ^[1]; Wyslouzil, Barbara E. ^[1]

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1. The Ohio State Univ., Columbus, OH (United States)

Heterogeneous nucleation of CO₂ onto H₂O ice particles may play an important role in proposed innovative CO₂ capture technologies, as well as in the formation of Martian clouds. In this work we follow the nucleation/condensation of CO₂/H₂O gas mixtures with microsecond resolution in supersonic Laval nozzles using pressure trace measurement (PTM) and small angle X-ray scattering (SAXS). The latent heat release detected by the PTM reveals that the first phase transition in the expanding CO₂/H₂O mixture is the formation of H₂O ice particles by the homogeneous nucleation/condensation and freezing of H₂O. This is followed by the heterogeneous nucleation and growth of CO₂ on the H₂O ice particles. The onset conditions for heterogeneous nucleation, i.e. the partial pressure of CO₂ and temperature from PTM and the radius of gyration of the H₂O ice particles from SAXS, were determined in the temperature range 124 to 146 K and for particles with radii of gyration in the range of 2.1 to 4.3 nm. The onset conditions suggest that the heterogeneous nucleation of CO₂ may start from the supercooled liquid phase under our conditions. Downstream of the onset point, the partial pressure of CO₂ and temperature rapidly approach the vapor–solid equilibrium line of CO₂, showing that even if CO₂ condensation is initiated by heterogeneous nucleation of the liquid phase, it proceeds via growth of the solid.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS); National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV, and Albany, OR (United States)
• Sponsoring Organization: National Science Foundation (NSF); USDOE Office of Science (SC)
• Grant/Contract Number: FE0013122; CHE-1213959; AC02-06CH11357
• OSTI ID: 1238294
• Journal Information: RSC Advances, Vol. 5, Issue 128; ISSN 2046-2069
• Publisher: Royal Society of Chemistry
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY