Low cost effective heterogeneous photo-Fenton catalyst from drinking water treatment residuals for reactive blue 19 degradation: preparation and characterization.

Four different catalysts from drinking water treatment residuals (DWTR) were prepared via impregnation in the iron nitrate, calcined at different temperatures ranged from 200°C to 500°C and tested for the reactive blue 19 oxidation using the heterogeneous photo Fenton, under UVA light source. XRD and XPS results revealed that iron nature was found under a ferric oxide form (Fe3+ ) similar to the magnetite. Calcination temperature results showed a significant effect on the activity of the catalysts. RB19 and TOC removals were 99% and 79%, respectively with the best catalyst that calcined at 500°C in optimal conditions as follows: initial pH solution= 3, 10 mM of H2 O2 dosage, 0,5g/L of catalyst loading, reaction temperature 35°C, and IUVA = 3.55 MW/cm2 for 50 mg/L of RB19. The reusability of the catalyst after three cycle showed complete removal of RB19 and 65% TOC removal.