Photocatalytic conversion of simulated EDTA wastewater to hydrogen by pH-resistant Pt/TiO2-activated carbon photocatalysts

摘要

The composite material, titanium dioxide acid-treated activated carbon (TiO2-AC), was synthesized by mechanical mixing method. Platinum (Pt) was selected as electron acceptor for TiO2-AC surface modification by photo-deposition method. XRD, SEM, BET, and PL were used for crystalline structure, morphology, specific surface area, and charge recombination analysis, respectively. The PL results indicated that both Pt and AC functioned in the enhancement of electrons and holes separation, which can improve the photocatalytic activity of TiO2 in EDTA-2Na simulated wastewater. The Pt/TiO2 AC exhibited better photocatalytic activities in the pH range of 4.0-7.2. The results verified that AC addition can retard the influence of pH on the photocatalytic activity of TiO2. EDTA-2Na degradation involved the mineralization of EDTA-2Na to carbon dioxide and hydrogen, and the degradation reaction reached equilibrium in 2 h with 59% cumulative removal efficiency. (C) 2014 Elsevier Ltd. All rights reserved.