TITLE:
Adsorption of Natural Surfactant on Sandstone in Enhanced Oil Recovery: Isotherms and Kinetics Studies
AUTHORS:
Monday Obekpa Michael
KEYWORDS:
Enhanced Oil Recovery, Critical Micelle Concentration, Interfacial Tension, Adsorption Kinetics, Surfactant, Saponin
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.13 No.7,
July
27,
2023
ABSTRACT: In chemical enhanced oil recovery, surfactants are injected into the
reservoir with the intention to lower interfacial tension (IFT) between the
water and oil phases, and thereby bring about efficient displacement of oil.
However, the adsorption of the surfactants to reservoir rock surfaces leads to the
loss and reduction in concentration of the surfactants, which in turn reduces
the overall efficiency of the oil recovery process, with attendant financial
losses. In this work, the adsorption of
Quillaja Saponaria (QS), a novel, natural, non-ionic surfactant, on
crushed sandstone reservoir rock is investigated. X-ray diffraction (XRD) study
of clean sandstone particles has been undertaken to determine the main
components present in the sand particles. The conductivity method was used to
measure CMC and the surfactant concentrations in aqueous solutions. Batch
adsorption experiments were used to determine the amount of QS adsorbed on rock surface. Equilibrium conditions were
reached after almost 5 days. From the results of the study, the Langmuir
isotherm model is more suited for predicting the adsorption behaviour of QS on
sandstone. The kinetic adsorption of QS obeys the pseudo-second order model.
This study is particularly relevant in surfactant selection for chemical EOR
processes.