Characterization and Preliminary Investigation of Alkylpolyglucoside Combined With a Biopolymer for Enhanced Oil Recovery

ABSTRACT Surfactant–polymer (SP) flooding is a promising Enhanced Oil Recovery (EOR) technique, combining improved displacement from surfactants with enhanced sweep efficiency from polymers. This study investigates two SP systems based on the biopolymer scleroxanthan (a blend of sclerotium gum and xanthan gum) and biodegradable surfactants: COCO (cocoglucoside) and MPG (cocoglucoside with glyceryl oleate). A pre‐salt crude oil (20° API) and synthetic brine were employed. Biocompounds were characterized by 1 H NMR, FTIR, and TGA, while the CMCs of COCO and MPG were determined. Surfactant–isopropanol mixtures at different volume ratios achieved minimum interfacial tensions of 0.18 mN/m (COCO, C/S 0.01 (v/v)) and 0.05 mN/m (MPG, C/S 0.3 (v/v)). Emulsion stability tests indicated that COCO–isopropanol with scleroxanthan improved stability, whereas MPG–isopropanol was more stable without the polymer. Contact angle measurements on carbonate rocks saturated with crude oil confirmed wettability alteration, with a 76% reduction for COCO and a 60% reduction for the SP system (MPG + scleroxanthan). These results indicate an efficient wettability shift from mixed‐wet (with a tendency toward oil‐wet) to water‐wet, enhancing the affinity of the injected fluid with the rock surface. Such findings highlight the potential of the developed fluids for enhanced oil recovery (EOR), warranting further evaluation under reservoir‐representative conditions.