Adsorption II. Nonequilibrium adsorption of surfactants onto three reservoir cores from the Norwegian Continental Shelf. The effects of clay minerals

✍ Scribed by T Austad; P.A Bjørkum; T.A Rolfsvåg

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 699 KB
• Volume: 6
• Category: Article
• ISSN: 0920-4105
• DOI: 10.1016/0920-4105(91)90032-i

✦ Synopsis

Three sandstone cores from different petroleum reservoirs on the Norwegtan Continental Shelf have been circulated with a surfactant mixture consisting of ethoxylated sulfonate and the corresponding alcohol for several weeks at 80°C A fast and a longtime, diffusion-controlled adsorption process has been detected This process Is related to the clay minerals. The kinetics of the &ffUSlOn-controlled adsorption process is simulated by a simple first-order rate equation in the available adsorption area. The value of the rate constants are discussed m relation to the mmeralogtcal properties of the kaolinate present in the cores. A &ffusion-controlled adsorption mechanism is proposed, suggesting that only surfaetant monomers are diffusing through the pore throats of the micropores Chemical analysis of the surfactant mixture shows that the concentration ratio between the amomc sulfonate and the nomonic alcohol changes dunng the whole adsorption process The variation in the concentration ratio can be related to the different core minerals being covered with surfactants at different times.