Selecting Optimum Formulation of Surfactant-Alkaline System for a Sudanese Crude Oil Experimentally

Abstract

The primary objective of this research is to obtain an optimum concentration of alkali, surfactant and salt that can achieve the ultra-low interfacial tension, previous studies have shown that high performing surfactant formulations that achieve the ultra-low interfacial tension can be identified by conducting the micro-emulsion phase behavior tests. Similarly, in this research, a sample of a Sudanese crude oil from South Annajma field was mixed at specific water oil ratio with several combinations of chemical components that include surfactant (Benzalkonium chloride (BAC)), alkali (sodium hydroxide(NaOH), sodium carbonates(Na2CO3)), as well as sodium chloride(NaCl) to carry out phase behavior experiments. Oven was used to heat up and maintain the mixture at the reservoir temperature that is 50o C for equilibration period of two hours and the test was conducted under 1 atm. Observations and recording of phase behavior experiment results show that the optimum concentrations of the chemicals are 5%wt surfactant, 5%wt Na2CO3, and 2%wt NaCl, as the best formulation based on this research. This values have achieved a reasonable ultra-low of the interfacial tension.