Application of semiconductor photocatalytic materials for the removal of inorganic compounds from wastewater

Abstract

Semiconductor Photocatalytic Materials for the Removal…?>A wide range of inorganic pollutants are sensitive to photochemical transformation on the surface of catalysts. The major inorganic wastewater pollutants treated by this process include cyanide-containing waste and heavy metal pollutants, such as arsenic species and hexavalent chromium. Heterogeneous photocatalysis has been explored as an alternative technology for inorganic ion removal offering satisfactory results. The photocatalytic removal of inorganic pollutants usually has two types of mechanisms: oxidation and reduction. In this chapter, the photocatalytic activities of various semiconductor materials for inorganic ion removal have been compiled and reviewed. The key advancements on the preparation of semiconductor materials tested for the removal of inorganic ions at low-level concentrations from natural water evaluating the matrix effects are also highlighted and discussed. In particular, the chapter focuses on enhancing the degradation efficiency; maximizing the use of illumination wavelength in the visible light region to develop solar active photocatalysts; the ease of separation from treated water, which is always of great interest; and improving the retrieval and reuse of semiconductors.