UV/solar light induced photocatalytic degradation of phenols and dyes by Fe(PS-BBP)Cl3

Abstract A polymer supported complex Fe(PS-BBP)Cl 3 [PS = chloromethylated polystyrene divinyl benzene; BBP = 2,6-bis(benzimidazolyl)pyridine] was prepared and characterized by elemental analyses, FT-IR and electronic spectral studies, AAS, magnetic moment measurement, BET surface area measurement and thermal analysis. Its photocatalytic properties were evaluated by studying the degradation of phenolic compounds (phenol, catechol, hydroquinone, p -chlorophenol, p -nitrophenol, o -cresol, p -cresol) and dyes (methyl orange, methyl red, rhodamine B) under UV light illumination to CO 2 and H 2 O in the presence of H 2 O 2 . The effects of important parameters such as concentration of Fe(PS-BBP)Cl 3 and substrates (phenol or methyl orange), amount of H 2 O 2 , and time have been investigated on the rate of degradation of phenol and methyl orange. Complete degradation of phenol and methyl orange occurred at room temperature with Fe(PS-BBP)Cl 3 under UV radiation in 30 and 120 min respectively. Experimental results indicated that the reactivity of Fe(PS-BBP)Cl 3 is more than its unsupported analogue. The intermediates formed during the process were identified using LCMS. Photoelectrochemical measurements (amperometry) carried out for Fe(PS-BBP)Cl 3 revealed the faster migration of photo-induced charge-carriers. The degree of mineralization was also confirmed by chemical oxygen demand (COD) experiments. The results indicated that these could be effectively decolorized and degraded by photocatalytic method, without generation of any hazardous wastes or by-products as evident from the considerable reduction in COD values. The photocatalytic activity of the supported complex in presence of solar light was also investigated.