Estimation of effective operating parameters for dye degradation using Bi3TiVO9 via tribocatalysis

Abstract

Bi3TiVO9 powder was used as a tribocatalyst for the removal of Rhodamine B (RhB) dye via tribocatalysis process. Bi3TiVO9 ceramic powder was synthesized using the solid-state reaction method and characterized using Raman spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The tribocatalytic activity was systematically evaluated at different stirring speeds of 200, 400, and 500 rpm, demonstrating a strong dependence on rotational speed. The maximum degradation efficiency of approximately 91% was achieved within 3 hours at 500 rpm. Additionally, the effect of pH on the degradation process was investigated, revealing enhanced catalytic performance under acidic conditions. The highest degradation rate, with a rate constant of 9.7 x 10(-3) min(-1), was observed at pH 3. Further, experimental observations showed that tribocatalytic efficiency was influenced by the reaction vessel material, with a glass beaker (91%) outperforming polyethylene (53%), and by the PTFE bead size, where a larger surface area enhanced degradation. Scavenger experiments further identified superoxide radicals (O-2(-)) as the dominant reactive oxygen species responsible for facilitating the degradation process.