Effects of factors and interacted factors on the optimal decolorization process of methyl orange by ozone

The decolorization of methyl orange by ozone is effectively carried out in this study. Factors affecting the decolorization rate of methyl orange are investigated by a 25−1 fractional factorial design method. The influences of the main factor and two-factor interaction effects of the operating variables of pH, reaction temperature, agitation rate and concentrations of methyl orange and ozone stream on decolorization are established. The results show that the effect of concentration of ozone stream is the most important among the five main factor effects. Interaction between temperature and ozone stream concentration is the most significant effect among the ten two-factor interaction effects. A quadratic form fit using a modified central composite experimental design is obtained, and it is proved to be adequate for this system according to the multiple correlation coefficient and variance analysis.