Degradation of nitroaromatic compounds: a novel approach using iron from laterite soil

The Fenton's oxidation process has been found to be a simple and economical method for the treatment of nitroaromatic compounds in water. In the present study, the iron extracted from the laterite soil was used as a catalyst and optimization of pH, hydrogen peroxide concentration and iron concentration was studied for different initial concentrations of 2-nitroaniline (2-NA), 3-nitroaniline (3-NA) and 4-nitroaniline (4-NA). The optimum pH obtained was 2.5 for 2-NA and 3-NA and 3 for 4-NA. The maximum removal efficiency obtained was 85.3%, 84.3% and 98.7% for 0.5 mM initial concentration at a hydrogen peroxide concentration of 3.5 mM, 4.5 mM and 5 mM for 2-NA, 3-NA and 4-NA, respectively, with a constant iron concentration of 0.05 mM.