TY - JOUR
T1 - Triple-layer surface complexation modelling
T2 - Characterization of oil-brine interfacial zeta potential under varying conditions of temperature, pH, oil properties and potential determining ions
AU - Saeed, Motaz Siddig
AU - Jadhawar, Prashant
AU - Zhou, Yingfang
AU - Abhishek, Rockey
N1 - Acknowledgements
Motaz Saeed would like to thank the University of Khartoum, Sudan and the Ministry of Higher Education and Scientific Research, Sudan for the financial support of his studies at the University of Aberdeen.
PY - 2022/1/20
Y1 - 2022/1/20
N2 - Low salinity water flooding (LSWF) is a popular enhanced oil recovery technique. Among factors that affect the performance of LSWF, geochemical interaction at the oil-brine interface and the associated enterokinetic properties plays a prominent role. This work presents a triple-layer surface complexation model for predicting the zeta potential of the oil-brine interface. We improve upon previous modelling studies by incorporating the effects of (1) temperature variation, (2) basic (-NH) oil surface group interactions (3) adsorption of sodium ions on outer and inner Helmholtz planes and (4) the presence of sulphate ions in brine. Model validation against published experimental data shows model accuracy between 66% and 99%. The model displays higher accuracies at lower salinities (making it particularly suited for LSWF applications), intermediate pH and higher total acid number. In addition, a correlation between (-NH) site density and total acid/base numbers is proposed. A sensitivity study performed utilising the developed model showed that higher sulphate concentration in the brine and elevated temperature makes the zeta potential at the oil-brine interface more negative. In addition, the sensitivity study indicates that a higher concentration of basic polar oil compounds is less favourable as it may result in less water-wet conditions in the reservoir.
AB - Low salinity water flooding (LSWF) is a popular enhanced oil recovery technique. Among factors that affect the performance of LSWF, geochemical interaction at the oil-brine interface and the associated enterokinetic properties plays a prominent role. This work presents a triple-layer surface complexation model for predicting the zeta potential of the oil-brine interface. We improve upon previous modelling studies by incorporating the effects of (1) temperature variation, (2) basic (-NH) oil surface group interactions (3) adsorption of sodium ions on outer and inner Helmholtz planes and (4) the presence of sulphate ions in brine. Model validation against published experimental data shows model accuracy between 66% and 99%. The model displays higher accuracies at lower salinities (making it particularly suited for LSWF applications), intermediate pH and higher total acid number. In addition, a correlation between (-NH) site density and total acid/base numbers is proposed. A sensitivity study performed utilising the developed model showed that higher sulphate concentration in the brine and elevated temperature makes the zeta potential at the oil-brine interface more negative. In addition, the sensitivity study indicates that a higher concentration of basic polar oil compounds is less favourable as it may result in less water-wet conditions in the reservoir.
KW - Oil-brine interface
KW - Zeta potential
KW - Surface complexation modelling
KW - Electric Triple Layer
KW - Low salinity waterflooding
KW - Wettability alteration
UR - http://dx.doi.org/10.1016/j.colsurfa.2021.127903
U2 - 10.1016/j.colsurfa.2021.127903
DO - 10.1016/j.colsurfa.2021.127903
M3 - Article
VL - 633
JO - Colloids and Surfaces. A, Physicochemical and Engineering Aspects
JF - Colloids and Surfaces. A, Physicochemical and Engineering Aspects
SN - 0927-7757
IS - Part 2
M1 - 127903
ER -