Preparation Of Honeycomb Fly Ash Catalyst And Its Application In SCR Process

As one of the main pollutants in the atmosphere,nitrogen oxides(NOx)are derived from the combustion of coal and fossil fuels.In China,the emissions from coal-fired power plants account for a large part.To reduce their pollution,I have done more on coal-fired power plants.For the denitrification reform,most of the technologies used are selective catalytic reduction denitrification(SCR).The technology of SCR is the catalyst.Although China has made some progress in the research of SCR catalysts,today's denitration catalysts are relatively expensive,mainly relying on foreign imports.How to reduce the price of domestic catalysts,making them more efficient,simple,and energy-efficient to prepare more efficient catalysts has become a hot spot for researchers.In the experiment,fly ash discharged from coal-fired power plants was selected as the catalyst carrier,and matrix binder bentonite,chemical binder,starch pore-forming agent,and glycerin auxiliary agent were added.The effects of different types and addition amounts of bentonite,chemical binders,starch pore-forming agents,glycerin squeeze additives and water-powder ratio on the catalyst's denitration performance and axial compressive strength were studied;equal volume impregnation method was used to load active components.The effects of Mn-Ce bimetal loading sequence and Mn-Ce molar ratio on the denitration performance and sulfur and water resistance of the denitration catalyst were studied.Using XRD,XPS,ICP,FTIR,SEM to characterize the catalyst and analyze its mechanism.Experiments show that when the ratio of fly ash and calcium-based bentonite is 4:1,the catalyst has higher axial strength and the highest denitration efficiency;when using silica sol and the amount of silica sol added is 6%,the support strength is most improved Obviously,the denitration effect is good;when the water powder ratio is 14%,the extrusion speed is the highest and the catalyst surface is smooth,the molding effect is the best;when the amount of the pore-forming agent starch is 6%,the catalyst specific surface area is the largest and the denitration effect is the best,And has little effect on the strength of the catalyst;when the amount of glycerin is 6%,the catalyst extrusion is the smoothest and the catalyst cracks are the least;when the Mn-Ce bimetal is used for simultaneous loading,Mn ions enter the CeO2 lattice to form Mn-O-Ce fluorite-structured solid solution makes the catalyst denitration performance the best and the sulfur resistance the best;the catalyst denitration performance increases first and then decreases with the Mn-Ce molar ratio.When the Mn-Ce molar ratio is 1:1,the catalyst The denitration efficiency is higher,the total conversin rate of NO is the highest and the deactivation time is the longest,and the catalyst has the best sulfur resistance.