Evaluation of surfactant synthesized from waste vegetable oil to enhance oil recovery from retroleum reservoirs

Abstract

Minimizing the loss of chemicals due to adsorption unto the rock materials during injection into petroleum reservoirs is critical to improve the economics and environmental footprint of the process and ensure its wider application. In this study, adsorption of a surfactant formulated from waste vegetable oil (SEMES) and two commercial surfactants, cetyltrimethyl ammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) onto common reservoir materials, at various concentrations, salinity and pH is compared. Indirect method of residual equilibrium concentration measurement was employed to obtain the adsorption isotherm of the surfactants on kaolin, silica, alumina and ilmenite. They were found to adsorb strongly onto the materials while stabilization in the region above the CMC was observed. At constant salinity, cationic surfactant adsorbed more strongly on the materials than the anionic surfactant. With increasing pH, the adsorption of SDS and SEMES decreased while the opposite was the case with the cationic surfactant, CTAB.