Regression modelling for concentration dependent mass density and specific volume of aqueous surfactant solutions

In the present work, mathematical models relating mass density and specific volume of solution with concentration for aqueous solutions of anionic (sodium lauryl sulfate - SLS) and cationic (cetyltrimethylammonium bromide - CTAB) surfactants (0-10% (w/w)) have been investigated. The experimental studies were performed to study the effect of solution concentration on mass density and specific volume of solution. Mass density increases, and specific volume decreases with an increase in solution concentration for both surfactants. Linear, quadratic, cubic, quartic, quintic, and exponential models were fitted to the experimental data to check the applicability. The models were validated based on the coefficient of determination (R2) and the sum of square of error (SSE) to be unity and zero, respectively. Modelling results reveal that the quintic model was fitted to study the effect of density on solution concentration for both surfactants. KEY WORDS: Density, Surfactant, Cetyltrimethylammonium bromide, Sodium lauryl sulfate, Modelling, Regression Bull. Chem. Soc. Ethiop. 2023, 37(4), 1047-1054. DOI: https://dx.doi.org/10.4314/bcse.v37i4.19