LAUSR

Abstract In this study, sonophotocatalytic decolorization of Begazol Black B by double-sided, sonoloaded nanophotocatalysts (nphs) on 3D porous substrate (3D-PS) was reported for the first time. Sonoloading is a facile fabrication route that allows two-sided loading of nphs on 3D-PS. Morphology of the 3D-PS and the presence of the nphs were studied using field emission scanning electron microscopy and energy dispersive X-ray spectroscopy, respectively. Moreover, the durability of the nphs on the 3D-PS was studied using X-ray fluorescence. The central composite design based on response surface methodology was employed to find the maximum yield of sonophotocatalytic decolorization and optimize the process variables (initial BBB concentration, initial H2O2 concentration, pH and ultrasonication time). Complete decolorization was achieved at only 40 min treatment under the optimum conditions. Moreover, sonoloaded nphs on 3D-PS exhibited 93% durability after 50 h sonophotocatalytic decolorization. The anticipated values of the decolorization efficiency showed excellent agreement with the experimental values (R2 = 0.9823, Adj-R2 = 0.9657). Furthermore, the kinetic analysis demonstrated that the sonophotocatalytic decolorization followed the Langmuir-Hinshelwood kinetic model. Finally, a comparative study between sonocatalytic, photocatalytic and sonophotocatalytic processes was conducted at the optimum condition. The results revealed that sonophotocatalytic process can markedly enhance the decolorization efficiency compared to sonocatalytic and photocatalytic methods due to the enhanced reactive radical generation.