Evaluation of Ultrasonic Oxidation of Diethyl Phthalate Using Box-Behnken Design with Response Surface Methodology

Evaluation of Ultrasonic Oxidation of Diethyl Phthalate Using Box-Behnken Design with Response Surface Methodology

The kinetic constant of diethyl phthalate (DEP) oxidized by ultrasound was measured as a function of ultrasound power density, <TEX>$Cl^-$</TEX> concentration and solution temperature. The ultrasonic oxidation kinetic of DEP could be described by the pseudo-first-order reaction d[DEP]/dt = -kCDEP, where k (<TEX>$min^{-1}$</TEX>) was identified using Box-Behnken Design coupled with Response Surface Methodology. The final equation for describing the kinetic constant k is as follows: Analysis of variance (ANOVA) tests showed that the second-order polynomial regression model could properly interpret the experimental data with a high determination coefficient (<TEX>$R^2$</TEX>, 0.998). The P-value of the model was 0.0001 which is less than 0.05, implying that the model is significant. Besides, the response surface showed that ultrasound power density gave much more effect than another two factors (temperature and <TEX>$Cl^-$</TEX> ion concentration), which provides a possible evidence for the future design.