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Indexed by:期刊论文

Date of Publication:2012-08-15

Journal:CHEMICAL ENGINEERING JOURNAL

Included Journals:SCIE、EI、Scopus

Volume:200

Page Number:729-737

ISSN No.:1385-8947

Key Words:Formaldehyde; Storage; Catalytic oxidation; Silver catalysts

Abstract:Catalytic removal of indoor HCHO was proposed to proceed in a "storage-oxidation" cycling process. Two kinds of supported silver catalysts, namely Ag/HZSM-5 and Ag-MnOx-CeO2. were investigated as catalysts for this cycling process. Due to the highly dispersed silver clusters formed and its good redox properties, the Ag-MnOx-CeO2 catalyst showed better HCHO oxidation properties in both the storage phase (HCHO partial oxidation to HCOO- at room temperature) and oxidation-regeneration phase (total oxidation of the formates into CO2 and H2O at elevated temperatures). The presence of H2O (RH = 50%, 25 degrees C) was found to enhance the HCHO storage capacity for Ag-MnOx-CeO2 catalyst, while competitive adsorption of HCHO with H2O was observed over Ag/HZ catalyst. The results of DRIFTS indicate that the partial oxidation of HCHO into HCOO- is accelerated by the presence of H2O over the Ag-MnOx-CeO2 catalyst. In addition, the catalyst saturated with HCHO can be in situ regenerated without production of secondary pollutants and can be used repeatly. It is suggested that this is a promising approach for indoor HCHO elimination. (C) 2012 Elsevier B.V. All rights reserved.