Visible Light Catalytic Reduction of Cr(VI) by Palygorskite Modified with CuO in the Presence of Tartaric Acid

摘要

A simple precipitation-calcination method was used to successfully prepare palygorskite (PAL)/CuO composite catalyst. As-prepared PAL/CuO composites were characterized by X-ray diffractions, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-vis diffused reflectance spectra. Photocatalytic activities of PAL/CuO composites were evaluated by the Cr(VI) reduction efficiency in the presence of tartaric acid under the illumination of visible light. Compared with a single component of PAL or CuO, the PAL/CuO composite catalyst showed outstanding photocatalytic performance, and Cr(VI) was completely reduced within 30 min. Effects of test parameters, such as initial pH, catalyst loading, and concentrations of tartaric acid, on the reduction efficiency of Cr(VI) have also been investigated. It is worth mentioning that the as-synthesized PAL/5.9CuO catalyst shows good reusability and can be effective in a wide range of pH (3-9) with quite high catalytic performance.