Molecular dynamics of CH₄/CO₂ on calcite for enhancing gas recovery

Abstract

The effect of temperature and pressure on the adsorption of CO 2 and CH 4 gases on calcite (104) has been studied by means of classical molecular dynamics. The results show that carbon dioxide greatly improves methane desorption in the 323-373 K range, even at low CO 2 concentrations. However, this effect is less pronounced for very high temperatures (423 K), where most of the methane is desorbed and CO 2 tends to desorb in large quantities. Radial distribution function (RDF) analysis reveals two distinct peaks for CO 2 (0.36 and 0.47 nm) and two for methane (0.87 and 0.57 nm) and the intensities of these peaks tend to decrease with increasing temperature. Such peaks are always clearly visible for CO 2, while the methane profile gets very broad already for mild conditions of temperature and CO 2 concentration. These results highlight how the CO 2

Preface to the special issue section honouring Professor Michael Williams

“…Carchini et al of Qatar University, University of Jordan, University of Burgos, and King Fahd University of Petroleum and Minerals (KFUPM) applied molecular dynamics simulation, a technique of strong interest to Professor Williams, to study the adsorption of methane and carbon dioxide on calcite (104) surface, a timely and important topic. [3] A paper contributed by Wong and Choi from the University of Alberta reports the application of proper orthogonal decomposition to analyze molecular dynamics simulation data so that the viscosity of polyethylene with different molecular structures can be evaluated. [4] The results are compared to those obtained by using a polymer-free volume theory.…”