title: Photocatalytic removal of organic pollutants in aqueous solution by Bi(4)Nb(x)Ta((1-x))O(8)I.
abstract: In this work, Bi(4)Nb(x)Ta((1-x))O(8)I photocatalysts have been synthesized by solid state reaction method and characterized by powder X-ray diffraction, scanning electron microscope and UV-Vis near infrared diffuse reflectance spectroscopy. The photocatalytic activity of these photocatalysts was evaluated by the degradation of methyl orange (MO) in aqueous solutions under visible light, UV light and solar irradiation. The effects of catalyst dosage, initial pH and MO concentration on the removal efficiency were studied, and the photocatalytic reaction kinetics of MO degradation as well. The results indicated that Bi(4)Nb(x)Ta((1-x))O(8)I exhibited high photocatalytic activity for the removal of MO in aqueous solutions. For example, the removal efficiency of MO by Bi(4)Nb(0.1)Ta(0.9)O(8)I was as high as 92% within 12 h visible light irradiation under the optimal conditions: initial MO concentration of 5-10 mg L(-1), catalyst dosage of 6 g L(-1) and natural pH (6-8), the MO molecules could be completely degradated by Bi(4)Nb(0.1)Ta(0.9)O(8)I within 40 min under UV light irradiation, and the photodegradation efficiency reaches to 60% after 7 h solar irradiation. Furthermore, the photocatalytic degradation of Bisphenol A (BPA) was also investigated under visible light irradiation. It is found that 99% BPA could be mineralized by Bi(4)Nb(0.1)Ta(0.9)O(8)I after 16 h visible light irradiation. Through HPLC/MS, BOD, TOC, UV-Vis measurements, we determined possible degradation products of MO and BPA. The results indicated that MO was degradated into products which are easier to be biodegradable and innocuous treated, and BPA could be mineralized completely. Furthermore, the possibility for the photosensitization effect in the degradation process of MO under visible light irradiation has been excluded.
authors.affiliation: School of Chemical and Environmental Sciences, Henan Key Laboratory for Environmental Pollution Control, Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Normal University, Xinxiang, Henan 453007, PR China.
authors.forename: Xing-Yun
authors.initials: XY
authors.lastname: Hu
authors.forename: Jing
authors.initials: J
authors.lastname: Fan
authors.forename: Ke-Lei
authors.initials: KL
authors.lastname: Zhang
authors.forename: Jian-Ji
authors.initials: JJ
authors.lastname: Wang
mesh_terms: D001391:Azo Compounds / Q000737:chemistry* / Q000528:radiation effects; D001559:Benzhydryl Compounds; D001729:Bismuth / Q000737:chemistry; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D004396:Coloring Agents / Q000737:chemistry* / Q000528:radiation effects; D052918:Environmental Restoration and Remediation / Q000379:methods*; D007455:Iodine / Q000737:chemistry; D013058:Mass Spectrometry; D009556:Niobium / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D010636:Phenols / Q000737:chemistry* / Q000528:radiation effects; D010782:Photolysis; D013635:Tantalum / Q000737:chemistry; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000528:radiation effects; D000098826:Bisphenol A Compounds
chemical_list: D001391:Azo Compounds; D001559:Benzhydryl Compounds; D001729:Bismuth; D004396:Coloring Agents; D007455:Iodine; D009556:Niobium; D010100:Oxygen; D010636:Phenols; D013635:Tantalum; D014874:Water Pollutants, Chemical; C100258:methyl orange; C006780:bisphenol A; D000098826:Bisphenol A Compounds