Study On Catalytic Combustion Of VOCs Over Perovskite Catalysts

VOCs is one of the main sources of air pollution.For the safe discharge of gaseous wastes, it is considered an effective method to treat VOCs with catalytic combustion. This study was basesd on the VOCs catalytic combustion over perovskite catalyst. Structure, specific area and grain scale of these catalysts were determined using XRD, BET, SEM method. The catalytic activities for toluene and mixed gas (toluene, cyclohexane and n-propanol) were evaluated by catalytic combustion equipment and Gas Chromotograpgy as ditecting method. Nanometer particle of LaCoO₃ and LaMnO₃ with pervskite structure were prepared by way of coprecipitation ; Redox titration showed that LaMnO₃ contains considerable amount of Mn4+(about 33.5%) in addition to Mn3+whereas Cobalt in LaCoO₃ was exclusively in the 3+ oxidation state; experiment of activity appraisal suggested that perovskite catalyst have good activity on toluene ,and the activity of LaMnO₃ was better than that of LaCoO₃, the same conclusion was drawn in the experiment of mixed gas catalytic combustion.In order to investigate the influence of partial replacement of La in perovskite catalyst on VOCs catalystic combustion, La₀. 8Sr_0.2CoO₃ and La_0.8Sr_0.2MnO₃ perovskite catalyst were prepared and catalytic combustion of VOCs with and without adding Sr were compared , The results showed...