Adsorption and Photocatalytic Properties of Modified Rectorite-Titanium Dioxide Composites

Abstract

Using rectorite as raw material, REC is modified by nitric acid, TiO2 is attached to the surface of the acidized modified REC tablet to form modified REC-TiO2 composite materials by the sol-gel method, and its adsorption performance and photocatalytic properties were studied. The results show that the adsorption of REC, modified REC, modified REC-TiO2 composite materialtoporads to methylene blue increased with the increase of equilibrium concentration. The process of adsorption MB of modified REC-TiO2 composite materials is an endothermic process. The adsorption of REC, modified REC, modified REC-TiO2 composite materials to MB increased with the increase of temperature. When the temperature is 25 degree, the maximum adsorption capacity of REC is 93.985 mg/g, the maximum adsorption capacity of modified REC is 107.006 mg/g, and the maximum adsorption capacity of modified REC-TiO2 is 120.773 mg/g. The degradation rate of MB and p-nitrophenol by modified REC-TiO2 composite under illumination are 99% and 98%, respectively. The decontamination rate of MB and 4-NP of modified REC-TiO2 composites under darkness was 50% and 0.8%, respectively. Under light conditions, the degradation rate of MB and 4-NP in modified REC-TiO2 composite materials is improved.