Kinetic study of the intercalation process of dimethylsulfoxide in kaolinite

A kinetic study of the intercalation reaction of dimethylsulfoxide (DMSO) into the layers of kaolinite was carried out. Several kaolinite-DMSO mixtures were analyzed at four temperatures (60, 50, 45 and 40 degrees C). Structural characterization was done by X-ray diffraction (XRD). The intercalation reaction was followed by XRD of the kaolinite-DMSO intercalates at different reaction times and temperatures. A kinetic analysis of the process was performed considering a two-step simple mechanism for consecutive reactions: ingress of DMSO molecules into the kaolinite galleries and subsequent rotation of DMSO molecules. Finally, the activation energies of the two steps proposed for the global intercalation process were estimated. (C) 2015 Elsevier B.V. All rights reserved.