Preparation Of Supported Noble Metal Nanocomposite Catalyst And Its Application In Catalytic Oxidation Of VOCs

Most of us usually think that sunlight and air are free gifts from nature,but it is often contrary to expectations.With people's increasing pursuit of a higher standard of living,people inevitably chose a pathway of treatment after development.After decades of rapid development,although enjoying the development achievements of development,we also have to endure the hazards of the creating environmental pollution.Therefore,we need to invest a lot of human and material resources in the field of environmental restoration.Air pollution in environmental pollution is particularly harmful to human health.The pollutants such as SO2,TSP,VOCs,photochemical oxides,and greenhouse gases emitted into the air have made the air worse.Among them,VOCs are difficult to be removed due to its variety and low concentration of single component.After a lot of research,the thermal catalytic oxidation method is the most promising approach to effectively remove low-concentration VOCs in the air.This technology is widely used because of its low cost,no secondary pollution,and high selectivity.In this paper,in order to eliminate low-concentration VOCs pollutants in indoor air and solve some problems in traditional thermal catalytic oxidation(such as excessive T90%,catalyst regeneration,etc.),different supported catalysts were prepared and used to remove VOCs in the air.The experimental results show that the supported noble metal catalyst can effectively reduce the temperature of catalytic degradation and completely decompose VOCs molecules to avoid secondary pollution.(1)Though a facile hydrothermal method,MnO2 nanoflowers were prepared and supported on CNTs for thermal catalytic oxidation of formaldehyde.This method has simple synthesis steps and we have easy access to raw materials.Consequently,a non-noble metal catalyst which owns excellent performance is synthesized.(2)SBA-15-OH was prepared as a hard silicon template while Pt/ZrO2 nanotube array was synthesized in a one-pot method,and it was combined with graphene to form an aerogel.Finally,the aerogel was modified by MOF-5 for thermal catalytic oxidation of formaldehyde.Graphene aerogel(GA)is conducive to the recycling of the catalyst,while the adsorption capacity of MOF-5 improves the catalytic efficiency.(3)Through cationic polymer-assisted synthetic strategy,zeolite gel powder containing platinum and palladium noble metal precursors was prepared.Then we get zeolite crystals through steam-assisted crystallization(SAC)technology and finally obtain the final product by washing,calcination,reduction and other steps.The catalysts are used for thermal catalysis toluene oxide.The pore structure of zeolite helps lock and protect precious metal nanoparticles and provides a large specific surface area for the catalytic reaction to proceed,which improves the reaction efficiency.