Behavior of water and methane bound to hydrophilic and hydrophobic nanosilicas and their mixture

Methane adsorption onto hydrated (0.1 g/g) initial and compacted nanosilica A-50 and compacted A-50/hydrophobic AM1 (based on nanosilica A-300) and water behavior vs. temperature were analyzed using H-1 NMR and theoretical methods. Methane adsorption increases with temperature because of changes in structure of mobile water. Stronger compaction of A-50 than that of A-50/AM1 (due to negative effect of AM1 preventing formation of tight contacts between A-50 nanoparticles) leads to decrease in adsorption of methane onto dense A-50 alone. These effects cause the difference in temperature behavior of bound water. (C) 2017 Elsevier B.V. All rights reserved.