Modification of clinoptilolite nano-particles with iron oxide: Increased composite catalytic activity for photodegradation of cotrimaxazole in aqueous suspension

Photocatalytic degradation of a pharmaceutical cotrimaxazole capsule in aqueous solution was studied using Iron oxide (IO) supported onto clinoptilolite nano-particles (NCP) and Hg-lamp as radiation source. The ball mill prepared NCP was ion exchanged in Ferrous chloride aqueous solution (0.3 M) for 24 h and then calcined at 450 degrees C for 12 h for preparation of the IO-NCP catalyst. The raw and modified samples were characterized by X-ray diffraction (XRD), Fourier transformation infrared (FT-IR), UV-vis diffuse reflectance spectroscopy (DRS) and Transmission electron microscope (TEM). Degradation extent of the pollutant was estimated by UV-vis spectroscopy and confirmed by COD and HPLC. Experimental parameters significantly affected the efficiency of the process and their optimum values were estimated as: 0.5 g L-1 of the photocatalyst, 50 folds diluted of the original solution (one capsule/100 mL) and pH 4.3. The proposed catalyst retained above 60% of its initial activity after 3 sequential re-using runs. (C) 2015 Elsevier Ltd. All rights reserved.