Decolorization of organic dye solution by ozonation; Optimization with response surface methodology

• Published in: International journal of industrial chemistry 2013, Vol.4 (1), p.3-3
• Main Authors: Kasiri, Masoud B, Modirshahla, Nasser, Mansouri, Hasan
• Format: Article
• Language: English
• Subjects: Chemistry; Chemistry and Materials Science; Environmental Chemistry; Industrial Chemistry/Chemical Engineering; Nanochemistry; Polymer Sciences
• ISSN: 2228-5970; 2228-5547; 2228-5547
• DOI: 10.1186/2228-5547-4-3

Background Ozone was used as a strong oxidant for decolorization of solution containing organic dyes. Three azo dyes, CI acid black 1 (AB1), CI acid yellow 19 (AY19) and CI acid orange 7 (AO7) which are widely used colorants in leather dyeing and finishing processes, were quantified with colorimetry. The effects of influential parameters including the ozone dosage, initial concentration of the dyes, initial pH of the solution, and temperature on the decolorization efficiency were studied. Central composite design (CCD) was applied to the optimization of decolorization of the dye solution by ozonation, and a second-order polynomial equation was proposed to predict the process efficiency. Results and discussion Predicted results were found to be in good agreement with experimental values ( R 2 = 0.9365, 0.9643, and 0.9296 for AB1, AY19, and AO7 respectively), which proves the suitability of the model employed and the success of CCD in optimizing the conditions of ozonation process. The variation of process efficiency as a function of independent variables was shown by graphical response surfaces. Conclusions It was found that response surface methodology could effectively predict and optimize the performance of ozonation process for decolorization of solution containing organic dyes, AB1, AY19, and AO7. Also, the optimum values of the process variables to achieve the maximum decolorization efficiency could be calculated and verified experimentally.