Adsorption/desorption of polymers from Saudi Arabian limestone

Adsorption of a synthetic copolymer and biopolymer (FLOCON 4800CT) onto Saudi Arabian limestone has been studied under the target conditions of temperatures (90°C) and salinity (200,000 ppm). The results show that whereas the copolymer is unsuitable at simulated reservoir conditions, the biopolymer exhibits low adsorption losses and maintains the required viscosities. The effect of pH, temperature, salinity and ethoxylated sulfonate addition on adsorption are studied in order to elucidate the mechanisms governing polymer adsorption. Dilution cycles conducted to study desorbability of polymer reveal the phenomenon of polymer readsorption. Heats of adsorption using flow microcalorimetry further identify the energetics of polymers adsorption onto limestone.