A Kinetic Approach to Photomineralization of Methane in Air by Membranes Based on TiO2/WO3  

作　　者：Ignazio Renato Bellobono Flavia Groppi Michela Sturini Angelo Albini Franca Morazzoni 

机构地区：[1]LASA,Department of Physics,University of Milan,Segrate(MI)I-20090,Italy [2]LASA,Department of Physics,University of Milan,and INFN(National Institute of Nuclear Physics),Segrate(MI)I-20090,Italy [3]Department of Chemistry,University of Pavia,Pavia 27100,Italy [4]Department of Materials Science,University of Milano Bicocca,Milan I-20126,Italy

出　　处：《Journal of Chemistry and Chemical Engineering》2020年第3期73-85,共13页化学与化工（英文版）

基　　金：The present paper is the 91st in a series of papers,authored by Ignazio Renato Bellobono and his collaborators over the past 35 years,which is collectively referred to as the“Photosynthetic Membranes”series.

摘　　要：Photomineralization of methane in air(10.0-1,000 ppm(mass/volume)of C)at 100%relative humidity(dioxygen as oxygen donor),was systematically studied at 318±3 K,in an annular laboratory-scale reactor,by photocatalytic membranes immobilising titanium dioxide and tungsten trioxide as co-photocatalysts.Kinetics of both substrate disappearance,to yield intermediates,and total organic carbon(TOC)disappearance,to yield carbon dioxide,were followed.A kinetic model was employed,from which,by a set of differential equations,four final optimised parameters,k1 and K1,k2 and K2,were calculated,able to fit the whole kinetic profile adequately.Modelling of quantum yields,as a function of substrate concentration and irradiance,as well as of concentration of photocatalysts,was carried out very satisfactorily.Kinetics of hydroxyl radicals reacting between themselves,leading to hydrogen peroxide,other than with substrate or intermediates leading to mineralization,were considered,paralleled by second competition kinetics involving superoxide radical anion.When using appropriate blends of the two photocatalysts,limiting quantum yieldsF∞values increase considerably and approach the maximum allowable value for the investigated molecule,in a much wider range of irradiances than that shown by the single catalysts mainly at low irradiances.This may be interpreted by strong competition kinetics of superoxide radicals generated by the catalyst defects,in the corresponding range of high irradiances.By this way,operation at high irradiance values is possible,without losing any efficiency for the mineralization process.

关 键 词：Titanium dioxide and tungsten trioxide co-photo catalysts photo catalytic membranes quantum yields gaseous methane mineralization kinetic modelling. 

分 类 号：O64[理学—物理化学]