Background: Design experiment stages of formalin mineralization process by center composition design (CCD) cause ease of work, reducing the number of samples, increasing the accuracy of optimized conditions and the interaction parameters determined during the process. The aim of this study was optimization of catalytic ozonation process for formaldehyde mineralization from synthetic wastewater by Fe/MgO nanoparticles synthesis by sol-gel method by response surface model.

Methods: This experimental study was conducted in a semi-batch reactor, using a RSM by taking 3 factors in the final stage of pH (7-9), reaction time (10-20 min) and catalyst dose (1.1-1.3 g/L) was investigated. Synthesis of nanoparticles was done by sol-gel method. The results were analyzed by Design Expert 7.0.1 software.

Results: The results showed that the process was dependent on the parameters studied and changing each parameter, affected the process efficiency and other parameters. The optimum conditions predicted for the process was 86.51% of mineralization efficiency. Optimum condition included pH=8.82, reaction time of 20 minute and catalyst dose of 1.3 g/L. The correlation coefficient for the process was determined 0.91.

Conclusion: Using a statistical model could reduce the number of experiments, the accuracy and the prediction process. The catalytic ozonation process has the ability to remove formaldehyde with high efficiency and the process was environmental friendly.