Perovskite-type titanate zirconate as photocatalyst for textile wastewater treatment

Calcium titanate zirconate, Ca(Ti_(1-x)Zr_x)O₃ (CZT), powders have been synthesised by the polymeric precursor method. The structural analysis of the CZT powders was monitored by X-ray diffraction (XRD), photoacoustic spectroscopy (PAS) and textural analysis. The photocatalytic properties were evaluated by methylene blue (MB) decomposition and real textile wastewater (RTW) combined treatment (coagulation/flocculation/photocatalysis). Chemical oxygen demand (COD) of RTW was successfully reduced from 6195 mg L^-1 (untreated) to 662 mg L^-1 after coagulation/flocculation with a tannin-based coagulant (Tanfloc®) and finally to 471 mg L^-1 after combined treatment (coagulation/flocculation/photocatalysis) applying ultraviolet radiation and CaTiO₃ as photocatalyst.