Experimental Study On Removal Of Multi-Pollutants From Flue Gas By Heterogeneous Catalytic Oxidation

During the combustion of coal,a large amount of conventional pollutants such as soot,sulfur dioxide,and nitrogen oxides are generated.Traditionally,the hierarchical treatment methods of flue gas dust removal,desulfurization,and denitrification have been adopted.There is a large area,high equipment investment and operating costs,and a systematic Complex and other disadvantages.Therefore,it is of great significance to develop integrated multi-pollutant removal technology.Iron spinel catalyst has excellent catalytic performance and can be used in photocatalytic advanced oxidation systems to achieve the integrated removal of gaseous multi-pollutants in flue gas.It has a simple process,low equipment investment and operating costs,and is suitable for non-electric industries.The characteristics of flue gas and other advantages,two kinds of iron spinel catalysts containing different metal ions were prepared in this paper,and the experimental research on the performance of photocatalytic denitration and simultaneous desulfurization and denitration based on iron-based catalysts was carried out on an experimental platform designed by ourselves.The specific research content is as follows:1.Five kinds of iron spinel catalysts containing different metal ions（Co,Mn,Bi,Ni,Zn）were prepared by the hydrothermal / solvothermal method.The hydrogen peroxide was used as the oxidant to conduct the catalytic oxidation NO denitratio n experiment.Two kinds of iron spinel catalysts with good catalytic performance were selected,and it was proved by means of characterization that the prepared catalysts were iron spinel substances.2.Using two kinds of iron spinel catalysts,the effects of catalyst addition amount,reaction temperature,solution p H and UV lamp wavelength on the removal efficiency were systematically studied,and different catalyst addition amounts,reaction temperature,solution pH and UV lamp wavelength were elaborated.The relationship and law with removal efficiency determine the best experimental conditions.When the catalyst is BiFeO₃ and the hydrogen peroxide concentration is3%,the amount of catalyst added is 2 g,the reaction temperature is 80 ℃,the pH of the solution is 5.0,the wavelength of the ultraviolet lamp is 185 nm,and SO₂ can be basically removed 100%.There is a competitive effect on hydroxyl radicals between SO₂ and NO in the gas,and the denitration efficiency can reach 68%;when the catalyst is ZnFe₂O₄ and the hydrogen peroxide concentration is 3%,the catalyst addition amount is 2 g,and the reaction temperature is 70 ℃,The pH of the solution is 5.0,the wavelength of the UV lamp is 185 nm,SO₂ can basically be 100%removed,and the denitration efficiency can reach 73%.