Objective of this master's thesis was optimization of the hydrogen peroxide-based product composition with design of experiments application. Firstly, screening design of experiments was used. One-quarter fraction factorial design with 32 experiments was used to investigate which of the chosen seven factors significantly affect stability of hydrogen peroxide in formulation and disinfectant efficacy of formulation. Rankit method was applied to analyze significancy of individual factor effects and two-factor interaction effects. The analysis results showed that partial neutralization has significant positive effect on stability of hydrogen peroxide in formulation whereas acid 2 has significant negative effect on stability. Acid 1 has markedly positive effect on disinfectant efficacy whereas partial neutralization and interaction between partial neutralization and acid 1 have significant negative effect on disinfectant efficacy. The other factors and interactions do not exhibit meaningful impact on the studied responses.
Based on the given results of screening design and empirical observations, optimization design of experiments was prepared. To optimize stability of hydrogen peroxide in formulation, disinfectant efficacy and foaming of formulation Box-Behnken design with three factors was used to prepare 16 experiments. Model coefficients were calculated by software using regression and then evaluated by analysis of variance. According to analysis of variance results, optimum prediction with these models is not logical since the models are not statistically significant. A model containing coefficients calculated by regression is therefore not statistically significantly different from a model containing only a constant equal to the mean response. None of the three factors significantly affect stability of hydrogen peroxide in formulation, only acid 1 has significant effect on disinfectant efficacy and only antifoam agent has significant effect on foaming. Nevertheless, a lot of new information about formulations was gained.
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