On the characteristics and stability of green emulsion made of Balanites aegyptiaca /neem oil in the presence of co‐surfactant

Conventional emulsion components are based on petroleum and commercial chemical agents which have a negative environmental impact. Here, our focus is on the mixing of Balanites Aegyptiaca /neem oil with several surfactants (Triton X‐100, SDS, and Tween 80) and co‐surfactants (Ethanol and Tween 20) at high salinity conditions ranging from 5 to 9 g/100 mL. Results showed that adding 0.396% (v/v) of Tween 20 as a co‐surfactant to the emulsion system contained 0.0194 g/100 mL of Triton X‐100 at 9 g/100 mL of NaCl was found to be the most effective emulsion system's formulation, forming a large stable emulsion volume of Winsor type IV with lower IFT (0.0005 mN/m), smaller contact angel (14.1°), higher density (1.03 g/mL) and viscosity (1.25 cP) with an average droplet size of 22.5 μm. Nevertheless, the addition of ethanol as a co‐surfactant led to a demulsification of the formed emulsion with a very poor stability effect. On the other hand, emulsion formed using TX‐100 surfactant in the presence of Tween 20 as a co‐surfactant successfully extended the emulsion stability.