Study On Photocatalytic Degradation Of H₂S Using Modiifcation Of The ACF/nano-TiO₂

In this paper, Using the activated carbon fiber as a carrier, Photocatalysts P25TiO₂/ACF loading of8.35%by Dip-dip method and Fe/TiO₂/ACF and Fe/Ce/TiO₂/ACFDoping of0.1%-0.7%by sol-gel method were prepared Respectively, and structure werecharactered by BET、TG-DTA、UV-Vis、XRD、SEM methods. As a target pollutant,Malodorous gases H₂S was to be adsorbed and Photolysis experimental study in theself-made photocatalytic reactor, and further explore the impact of various factors on theexperimental. The reaction product were observed and analized by the visual image、SEM、XRD、EDS meother, and then pushed to the reaction mechanism for the theoreticalbasis of H₂S photocatalytic degradation and adsorption.The structural characterization shows that the photocatalyst prepared by the sol-gelmothod Load evenly, form a stable dense film, and has the larger specific surface area. inthe calcination temperature of500°C, the photocatalyst showed anatase titanium dioxide,Modified iron doping expand the scope of the spectral response, and When co-dopedconcentration was0.3%, the absorption edge was largest.The basic experimental results show that ACF played the role of adsorption only inthe condition of absence light, and the rate was lower obviously than light conditions, andthe rate of the sol-gel method increased by4.2%and33.4%than Dip-dip method andblank ACF. Through the comparison of the different loading and ion doping experiments,the best photocatalyst was determined, that was two-layer coating Fe/TiO₂Fe/Ce/TiO₂modified photocatalysts prepared by the sol-gel mothod, and efficiency can reached78.1%and82.1%.On the basis of the best photocatalyst above, choosing Initial concentration, gas flowand photocatalyst loading amount as influencing factors, to explore the relationshipbetween the three factors and H₂S photocatalytic degradation and adsorption rate, thendesign three factors and three levels of orthogonal experiment. The results show that thebest combination are as follow, initial concentration is89.56mg/m3, loading capacity2-slices, gas flow rate is10L/h. The R value of orthogonal test showed that gas flow is thegreatest impact, followed by initial concentration, the loading amount is minimal impact.Reaction product analysis showed that a yellow substance was formed on the ACF,EDS spectra show a certain proportion of S elements, XRD diffraction peak of S, whichcan explain the reaction products of sulfur single mass. the main mechanism is the adsorption, catalytic oxidation reaction.