Application of mesoporous C- and C,N-codoped TiO2 in the removal of diclofenac from water was studied. The sol-gel method was used for the preparation of the photocatalysts. The physicochemical properties of studied materials were characterized by BET (Brunauer, Emmett and Teller), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy and X-ray diffraction (XRD) methods. XPS confirmed the incorporation of nitrogen and carbon atoms into TiO2 lattice. The synthesized catalysts were effective in the removal of the studied pollutant from water and enabled reduction of the COD (chemical oxygen demand) value of the wastewater by at least 60%. The process of diclofenac photooxidation over the C,N-codoped and C-doped TiO2 photocatalysts proceeded similarly and was followed by pseudo-first order kinetics. The increase in calcination temperature resulted in the rutile fraction (5%) slightly lowering the effectiveness of treatment. The results over pure anatase structures confirmed that anatase has usually a better photocatalytic activity than rutile. The best changes in the water quality were observed during the first 50 min of treatment, but mineralization of pollutant did not lead to complete.
Polymer (XAD7HP)/Ti4+ nanocomposites were prepared through the swelling of polymer in titanium (IV) ethoxide as a titanium dioxide precursor. The nanocomposite beads exhibit relatively high porosity different than the porosity of the initial polymer. Thermal treatment of composite particles up to 200 °C in vacuum causes the change of their internal structure. At higher temperature, the components of composite become more tightly packed. Calcination at 600 °C and total removal of polymer produce spherically shaped TiO2 condensed phase as determined by XRD. Thermally treated composites show the substantial change of pore dimensions within micro- and mesopores. The presence of micropores and their transformation during thermal processing was studied successfully by positron annihilation lifetime spectroscopy (PALS). The results derived from PALS experiment were compared with those obtaining from low-temperature nitrogen adsorption data.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.