Interaction of Estonian kukersite with organic solvents: A volumetric swelling and molecular simulation study

This article describes the swelling of Estonian kukersite and isolated kerogen in 14 organic solvents. The swelling behaviour of kerogen represented by its molecular model is atomically simulated using the General Amber Force Field (GAFF). The characteristic features of the swelling behaviour of kukersite are identified, i.e. modest swelling ratios and their significant increases in specific H-bonding solvents. The swelling of the isolated kerogen and the cohesive energy density were found to be close to those of native kukersite. For non-H-bonding solvents, the total solubility parameter value is estimated to fall between 19 and 20 MPa1/2. This fits well with the value determined analogously for other type I-II kerogens. The value of the dispersion component of the solubility parameter calculated by the atomistic molecular simulation equals 18.9 ± 0.55 MPa1/2. Electrostatic components were found to play a minor role.