Development of magnetically recyclable nanocatalyst for enhanced Fenton and photo-Fenton degradation of MB and Cr(VI) photo-reduction

The present work reports the facile green synthesis of Fe3O4 magnetic nanoparticles (MNPs) and their Fenton and photo-Fenton catalytic activity for reduction reactions. The glucose-mediated MNPs exhibit spherical morphology with an average diameter of 6.3 +/- 1.1 nm. The catalytic activity of MNPs evaluated for Fenton and the photo-Fenton reactions resulted in 92 and 93% dye degradation in just 120 and 75 min, respectively. The magnificence of this novel synthesis methodology is the higher efficiency of both processes at varied pH ranges. Different catalytic parameters like wide pH range, catalyst dose, and H2O2 concentrations have made it more effective for both processes. Besides, the reusability study showed 63.71 and 57.57% activity even after six cycles in Fenton and photo-Fenton processes, respectively. The scavenger study showed the involvement of center dot OHads over center dot OHfree in the Fenton process, where center dot OH was found as a prime source of dye degradation in the photo-Fenton process. Moreover, Fe3O4 MNPs successfully reduced the 80 ppm load of Cr(VI) within 25 min, which improved further to 15 min by adding a chelating agent. This Fenton and photo-Fenton magnetically reusable catalyst will indulge the development of water treatment in an eco-friendly and economical way with great potential.