Adsorption behavior of cocamidopropyl betaine under conditions of high temperature and high salinity

ABSTRACT The adsorption behavior of cocamidopropyl betaine (CAB) in aqueous solutions and on sandstone surfaces was studied under the conditions of high temperature and high salinity. In aqueous solutions, as temperature increased from 25 to 90°C and salinity increased from 0 to 115,200 ppm, surface tension and the critical micelle concentration (cmc) of CAB both decreased. In the solid/liquid system, when the CAB concentration of salt solutions reached 0.30 wt %, the static saturation adsorption amount on the surface of clean sands was 14.77 mg g −1 at 90°C. Because of its noticeable saturation adsorption capacity, the adsorption of CAB on the solid/liquid interface agreed with multilayer adsorption. Also, the adsorption amount on the surface of oil sands was greater than on clean sands. Besides, the dynamic saturation adsorption amount and retention amount of 0.07 wt % CAB solution were less than the static adsorption amount. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131 , 40424.