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Microscopic structure and solubility predictions of multifunctional solids in supercritical carbon dioxide: a molecular simulation study

Noroozi, J ; Sharif University of Technology

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  1. Type of Document: Article
  2. DOI: 10.1021/acs.jpcb.6b12390
  3. Abstract:
  4. Molecular dynamics simulations were employed to both estimate the solubility of nonelectrolyte solids, such as acetanilide, acetaminophen, phenacetin, methylparaben, and lidocaine, in supercritical carbon dioxide and understand the underlying molecular-level driving forces. The solubility calculations involve the estimation of the solute's limiting activity coefficient, which may be computed using conventional staged free-energy calculations. For the case of lidocaine, wherein the infinite dilution approximation is not appropriate, we demonstrate how the activity coefficient at finite concentrations may be estimated without additional effort using the dilute solution approximation and how this may be used to further understand the solvation process. Combining with experimental pure-solid properties, namely, the normal melting point and enthalpy of fusion, solubilities were estimated. The results are in good quantitative agreement with available experimental data, suggesting that molecular simulations may be a powerful tool for understanding supercritical processes and the design of carbon dioxide-philic molecular systems. Structural analyses were performed to shed light on the microscopic details of the solvation of different functional groups by carbon dioxide and the observed solubility trends. © 2017 American Chemical Society
  5. Keywords:
  6. Carbon dioxide ; Free energy ; Molecular dynamics ; Molecular structure ; Solvation ; Free-energy calculations ; Limiting activity coefficient ; Microscopic structures ; Molecular dynamics simulations ; Molecular simulations ; Quantitative agreement ; Solubility calculations ; Supercritical carbon dioxides ; Supercritical fluid extraction ; Carbon ; Simulation ; Solubility
  7. Source: Journal of Physical Chemistry B ; Volume 121, Issue 7 , 2017 , Pages 1660-1674 ; 15206106 (ISSN)
  8. URL: https://pubs.acs.org/doi/abs/10.1021/acs.jpcb.6b12390