Response Surface Methodology as an Approach to the Optimization of a Dishwashing Detergent

Abstract

Abstract The response surface methodology (RSM) was used to optimize the washing performance, viscosity, (cloud point) and turbidity of a model hand dishwashing (light duty) liquid detergent. Homogeneous mixtures of four ingredients represented typical formulations: an anionic surfactant (sodium linear alkylbenzenesulphonate, LAS, MW ∼350), a nonionic surfactant (C16 – C18 range ethoxylated alcohol with 11–12 EO), a 80/20 v/v glycerol/water mixture and an inorganic electrolyte (NaCl). The Statistica® software, and especially its (Design of Experiments) module, was used to model the above-mentioned properties (response functions) and to find out the best formulation with the help of the desirability profiler. RSM mainly helps to select regions of the experimental design where cloud point values are acceptable. Results show that, at high levels of anionic species, cloud point values are very sensitive to salt addition.