Solar assisted degradation of carbendazim in water using clay beads immobilized with TiO_2 & Fe doped TiO_2

摘要

The current work emphasized on the sunlight based photocatalytic application of TiO2 and iron doped TiO2 (Fe-TiO2), immobilized over the novel, eco-friendly support material developed as clay beads (CL), and placed in a newly developed Flat Plate Photocatalytic Reactor (FPPR). For catalyst immobilization, simple heat attachment method was applied using double distilled water as solvent for 2% (by weight) of TiO2 and Fe-TiO2 separately. Clay beads were characterized by Scanning Electron Microscope (SEM), Electron Dispersive Spectroscopy (EDS) and Brunauer Emmett Teller (BET) analysis for their structural, electronic & textural properties respectively; whereas characterization of Fe-TiO2 was performed using Field Emission Scanning Electron Microscope (FESEM), EDS, Transmission Electron Microscopy (TEM), X-ray Diffraction spectroscopy (XRD) and Diffuse reflectance spectrometer (DRS). A benzimidazole fungicide, Carbendazim (CBZ) was taken as the reference water pollutant and catalyst coated beads were further applied for its degradation using the FPPR. Remarkable degradation (87 +/- 1% average) of CBZ was observed for 40 successful cyclic studies over the Fe-TiO2 coated CL beads under sunlight, without performing any reactivation of catalyst. Whereas highest degradation of CBZ achieved under sunlight conditions was 93 +/- 4.65%. Effect of various reaction parameters was analyzed using UV-Visible spectroscopy, and the mineralization of CBZ was confirmed by Chemical oxygen demand (COD) and Gas Chromatography Mass Spectroscopy (GC-MS) analysis.