Catalytic Combustion Of VOCs On CuMnO_x/γ-Al₂O₃ Catalysts

Volatile Organic Compounds(VOCs)are the pervading effluents of industrial production.The conventional treatment of VOCs is adsorptive process.This method has the advantages of low cost and easy operation while it can't eliminate fundamentally the VOCs.It can transform from VOCs to H20 and CO2 to use the catalytic combustion process.This method can eliminate fundamentally the VOCs and recycle part of heat.Catalytic combustion is a process of flameless combustion and its temperatures of initiation and complete reaction are lower than the process of flame combustion.So it is to avoid the generation of NOx.Catalytic combustion of VOCs on CuMnOx/γ-Al2O3 catalysts is studied in this article.And it can be divided into two parts.(1)Preparation and activity determination of the catalysts.CuMnOx/γ-Al2O3 was prepared to use the method of dipping in this experiment.And it was characterized by SEM,XRD and BET.Toluene was instead of VOCs in the experiment.The experiment shows that the most suited atomic ratio of Cu and Mn is 1:2 and the catalysts loaded in 6%to 8%show more activity.Catalysts of CuMnOx/γ-Al₂O₃ were prepared under different temperatures of 300℃,400℃,500℃,600℃and 1000℃.And the one prepared under 600℃showed more activity.It was also studied the influence of airspeed,consistency of VOCs and the temperature.It was found that the efficiency became lower when airspeed became faster and the consistency of VOCs had little influence to the efficiency.It was found the optimum reaction conditions were:loading is 8%,airspeed is 1s^-1,consistency of toluene is 1800mg/m³ and the temperature is 320℃.It was also found that elements of VOCs had weak influence to the catalytic combustion.(2)Studied on process integration of desorption using microwave and catalytic combustion.It was found that this technics is a perfect treatment of VOCs.It solved the problem of lacking of oxygen to add in air with the ratio of 1:1 in the process of catalytic combustion It was also found that the efficiency of the process was running above 90% when the temperature of desorption was 400℃.