ASPHALTENE ADSORPTION ON KAOLINITE CHARACTERIZED BY INFRARED AND X-RAY-ABSORPTION SPECTROSCOPIES

The petroleum industry has observed that the trapping of oils in sedim entary rock is largely correlated to the presence of kaolinite clays i n the rock's intergranular space. Using X-ray absorption and Fourier t ransform infrared (FTIR) spectroscopies, we studied at the microscopic level the adsorption process of asphaltenes in the presence and absen ce of water. We shaw that oil modifies the local environment of alumin um in this material and, more precisely, the AI-OH linkage. Finally, w e show evidence that the process involved is different when the adsorp tion is performed with or without water. (C) 1998 Elsevier Science B.V . All rights reserved.