Fig. 7

UV-Visible spectra of treated solution by (a) photocatalysis using HAp, (b) photooxidation using HAp, (c) photocatalysis using HAp-nTiO2, (d) photooxidation using HAp-nTiO2, (e) photocatalysis using TiO2, and (f) photooxidation using TiO2 [Initial MV concentration = 25 mg L− 1, H2O2 = 10− 4 M, catalyst dosage = 0.25 g L− 1]