Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
J Environ Health Sci Eng. 2014 Feb 5;12(1):45. doi: 10.1186/2052-336X-12-45.
Mono aromatic hydrocarbons (BTEX) are a group of hazardous pollutants which originate from sources such as refineries, gas, and oil extraction fields, petrochemicals and paint and glue industries.Conventional methods, including incineration, condensation, adsorption and absorption have been used for removal of VOCs. None of these methods is economical for removal of pollutants of polluted air with low to moderate concentrations. The heterogeneous photocatalytic processes involve the chemical reactions to convert pollutant to carbon dioxide and water. The aim of this paper is a comparison of Benzene & Toluene removal from synthetic polluted air using a Nano photocatalytic TiO2/ ZNO process.
The X-ray diffraction (XRD) patterns showed that Nano crystals of TiO2 and ZNO were in anatase and rutile phases. Toluene & benzene were decomposed by TiO2/ ZNO Nano photocatalyst and UV radiation. Kruskal-wallis Test demonstrated that there are significant differences (pvalue < 0.05) between pollutant concentrations in different operational conditions.
Degradation of toluene & benzene increases with increasing UV intensity and decreasing initial concentrations. Effect of TiO2/ZNO Nano photocatalyst on benzene is less than that on toluene. In this research, Toluene & benzene removal by TiO2/ZNO and UV followed first-order reactions.
单芳烃(BTEX)是一组危险的污染物,来源于炼油厂、天然气和石油开采场、石化、油漆和胶水等行业。传统的方法,包括焚烧、冷凝、吸附和吸收,已被用于去除 VOCs。这些方法都不经济,无法去除低浓度到中等浓度污染空气中的污染物。非均相光催化过程涉及化学反应,将污染物转化为二氧化碳和水。本文的目的是比较使用纳米光催化 TiO2/ZNO 工艺从合成污染空气中去除苯和甲苯。
X 射线衍射(XRD)图谱表明,TiO2 和 ZNO 的纳米晶体处于锐钛矿和金红石相。甲苯和苯通过 TiO2/ZNO 纳米光催化剂和 UV 辐射分解。Kruskal-Wallis 检验表明,在不同操作条件下,污染物浓度存在显著差异(p 值 < 0.05)。
随着 UV 强度的增加和初始浓度的降低,甲苯和苯的降解率增加。TiO2/ZNO 纳米光催化剂对苯的影响小于对甲苯的影响。在这项研究中,TiO2/ZNO 和 UV 对甲苯和苯的去除遵循一级反应。