Degradation of p-Nitrotoluene in aqueous environment by Fe(II)/Peroxymonosulfate using full factorial experimental design

ABSTRACT

In this project, the removal of p-Nitrotoluene (PNT) in typical synthetic wastewater was investigated using Peroxymonosulfate (PMS) motivated by Ferrous Ion. The PNT was degraded by sulfate and hydroxyl radicals. The effect of various factors such as ferrous ion and PMS concentrations, and pH on the removal of PNT was studied. Three-level full Factorial design of experiments (FFD) was employed for experimental design and statistical analysis. It was revealed that the PMS and ferrous ion concentrations and quadratic terms were statistically significant while the factor interactions were insignificant model terms. Increasing the PMS and ferrous ion concentrations enhanced the PNT removal efficiency to some extent. The pH had two-contrast influence and the neutral pH was the best. The most significant term was the concentration of ferrous ion, which influenced greatly on PMS and considerably caused a change in the PNT removal efficiency. R-squared, as a measure of the amount of variation around the mean explained by the model was 0.9827. The maximum removal condition was obtained at pH of 7, ferrous ion concentration of 12 mM and PMS concentration of 25 mM. The maximum removal of PNT and COD was achieved as 96% and 67%, respectively.

KEYWORDS:

• Sulfate radical
• potassium Peroxymonosulfate
• advanced oxidation processes
• p-Nitrotoluene

Disclosure statement

The authors declare no conflict of interests.