▎ 摘　　要

NOVELTY - Preparing flue gas denitration catalyst comprises e.g. (i) adding graphene oxide powder, polyethylene glycol 400, manganese stearate to water and mixing to form suspension; (ii) soaking extruded open-cell polyurethane sponge in suspension and removing pressing force, allowing suspension to enter open-cell polyurethane sponge and ultrasonically shaking; (iii) placing suspension immersed in open-cell polyurethane sponge in freeze dryer, cooling and drying under vacuum in gradient heating manner to obtain mixed sponge; (iv) placing obtained mixed sponge in heating furnace, heating to decompose, removing polyurethane and cooling, reducing graphene oxide using hydrazine hydrate vapor and cooling to obtain large-pore graphene sponge structure; (v) soaking large-pore graphene sponge structure in mixture solution, applying ultrasonic vibration and cooling to room temperature; (vi) drying above treated graphene sponge structure; and (vii) calcining dried graphene sponge structure. USE - The method is useful for preparing flue gas denitration catalyst. ADVANTAGE - The flue gas denitration catalyst has structural characteristics of macroscopic pore size and microscopic small pore diameter, can remove low concentrations of nitrogen oxides in flue gas without affecting the efficiency of flue gas passing and denitration rate is greater than 90%. DETAILED DESCRIPTION - Preparing flue gas denitration catalyst comprises (i) adding graphene oxide powder, polyethylene glycol 400, manganese stearate to water and mixing to form suspension; (ii) soaking extruded open-cell polyurethane sponge into above suspension and removing pressing force, allowing the suspension to enter open-cell polyurethane sponge and ultrasonically shaking for 20-30 hours; (iii) placing suspension immersed in open-cell polyurethane sponge in freeze dryer, cooling to -35 degrees C and drying under vacuum of 3-5 Pa in gradient heating manner to obtain mixed sponge; (iv) placing obtained mixed sponge in a heating furnace, heating to 320-350 degrees C under nitrogen atmosphere of 0.1-0.4 MPa and keeping for 45-60 minutes to decompose and removing polyurethane and cooling to 95 degrees C, reducing graphene oxide using hydrazine hydrate vapor having a mass fraction of 80% after 24 hours and cooling to room temperature to obtain large-pore graphene sponge structure; (v) soaking large-pore graphene sponge structure in mixture solution, applying ultrasonic vibration, where temperature of mixture solution is 60-80 degrees C, rapidly cooling to room temperature after soaking for 12-15 hours, where mixture solution comprises 6-8% vanadium pentoxide, 15-18% tungsten trioxide, 30-35% titanium dioxide, 2-3% manganese stearate, 10-15% porous quartz powder, 2-3 methyl cellulose and water; (vi) drying above treated graphene sponge structure; and (vii) calcining dried graphene sponge structure.