Decolorization of Rhodamine B using activated sodium percarbonate by ultrasound and MgMn2O4 spinel nanoparticles

The current work demonstrates the effectiveness of the simultaneous activation of sodium percarbonate (SPC) by ultrasound (US) and MgMn₂O₄ spinel nanoparticles for the efficient decolorization of the Rhodamine B (Rh B) dye. MgMn₂O₄ spinel nanocatalyst was synthesized using the co-precipitation approach in the presence of ultrasound, followed by subsequent characterization using XRD, SEM, and FTIR analysis. The effect of several factors, such as SPC concentration, pH, catalyst dosage, and specific power of US, on the decolorization of Rh B has been studied. Experimental results demonstrated that Rh B (initial concentration in aqueous solution – 0.209 mM) could be efficiently decolorized (98 % in 60 min) by the US/MgMn₂O₄/SPC system. The best conditions for the Rh B decolorization were obtained as pH of 3, the initial SPC concentration of 5 mM, catalyst loading of 1.0 g/L, and the specific power of US of 51 W/L. Scavenging experiments elucidated that HO^• and ¹O₂ played a dominant role in the decolorization of Rh B using the US/MgMn₂O₄/SPC process. The synthesized MgMn₂O₄ spinel nanocatalyst showed excellent reusability for recycle (92.3 % removal of Rh B after four cycles).