title: Toluene removal from waste air stream by the catalytic ozonation process with MgO/GAC composite as catalyst.
abstract: This paper investigates the catalytic potential of MgO/GAC composite for toluene elimination from waste air in the catalytic ozonation process (COP). The MgO/GAC composite was a micro-porous material with the BET surface area of 1082m(2)/g. Different functional groups including aromatic CC, saturated CO of anhydrates, hydroxyl groups and SH bond of thiols were identified on the surface of MgO/GAC. Effects of residence time (0.5-4s), inlet toluene concentration (100-400ppmv) and bed temperature (25-100°C) were investigated on degradation of toluene in COP. Impregnation of GAC with MgO increased the breakthrough time and removal capacity by 73.9% and 64.6%, respectively, at the optimal conditions. The catalytic potential of the GAC and MgO/GAC for toluene degradation was 11.1% and 90.6%, respectively, at the optimum condition. The highest removal capacity using MgO/GAC (297.9gtoulene/gMgO/GAC) was attained at 100°C, whereas the highest removal capacity of GAC (128.5mgtoulene/gGAC) was obtained at 25°C. Major by-products of the toluene removal in COP with GAC were Formic acid, benzaldehyde, O-nitro-p-cresol and methyl di-phenyl-methane. MgO/GAC could greatly catalyze the decomposition of toluene in COPand formic acid was the main compound desorbed from the catalyst. Accordingly, the MgO/GAC is an efficient material to catalyze the ozonation of hydrocarbon vapors.
authors.affiliation: Department of Environmental Sciences, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Rezaei
authors.affiliation: Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran. Electronic address: moussavi@modares.ac.ir.
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Moussavi
authors.affiliation: Department of Environmental Sciences, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Iran.
authors.forename: Alireza Riyahi
authors.initials: AR
authors.lastname: Bakhtiari
authors.affiliation: Department of Chemistry, Faculty of Basic Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Yadollah
authors.initials: Y
authors.lastname: Yamini
keywords: Aromatic hydrocarbons; Catalyst; Catalytic ozonation; Magnesium oxide; Toluene