Experimental Study On Photocatalytic Degradation Of Gas

China is the world’s worst coal mine disasters in one of the countries, especially the gas accident is the most serious accident. More than 90% of the gas is methane, methane is composed only by the non active C-H key, which is a tetrahedral structure. Its molecule is very stable. The transformation and decomposition of methane is hard to occur under normal conditions. In this paper, the preliminary experimental research on degradation of gas in a home-made photoreactor using photocatalytic oxidation technology, provides the theory foundation for the green management of coal-mine gas(CMG,methane).First, this paper examined the influence on the vacuum ultraviolet degradation gas effect of different factors from the kinetics angle and simulated the gas degradation theoretically. Then the catalytic performance of different catalysts was also studied. Finally, selected zeolite ZSM-5 as the catalyst, invested and analysed reaction time, light intensity, oxygen(O2) content, water vapor(H2O) content and the coating area ratio on the degradation efficiency of CMG by orthogonal test, the optimal experimental conditions were determined.The results showed that, initial concentration of methane, light intensity, oxygen content, water content were the main factors affecting the vacuum ultraviolet oxidation degradation of coal mine gas. In this paper, using pseudo first order reaction kinetics model analysed the mechanism of hydroxyl radical and vacuum ultraviolet synergistic degradation gas, the reaction kinetics equation fitting correlation coefficient obtained more than 0.98. When ZSM-5 zeolite with Si/Al ratio was 150, for the initial 3.5% volume fraction of methane, gas degradation rate reached 86.40% under the optimized experimental conditions of irradiation intensity 4 W, O2 content 30 %, H2 O content 0.3 %, the coating area ratio 75 % after 120 min. If there was no catalyst, under the same experimental conditions, the gas degradation rate was only 66.61%.