Preparation Of Catalyst For Denitrification And Desulfurization Using Raw Sludge And Metal Oxide

A kind of catalyst for NO removal was prepared using surplus sludge from a municipal sewage treatment plant as raw material, with the method of impregnating surplus sludge in ZnCl₂ , Fe(NO₃)₃ and Mn(NO₃)₂ solution and then pyrolyzing it at high temperature. The catalyst efficiency for selective catalytic reduction of NO by CO and its lifetime were evaluated in a gas-solid catalytic microreactor. Based on different active matter laden and pyrolysis temperature, 16 types of carbonaceous catalysts were prepared. The experimental results indicate that the catalyst that obtained under the condition : Fe:Mn molar ratio was 3:1and pyrolysis temperature was 650℃has a better catalytic activity at 350⁵50℃,and the maximum conversion of NO can reach 97.1% at 450℃. After being tested for 660 minutes, the catalyst activity only decreased 3% approximately. The result also show that the catalyst has a good catalytic activity for desulfurization and dentrification simultaneously at the CO condition. At 400⁵50℃, the conversion of NO can reach over 90.0% and the maximum conversion can reach 95.6% , at the 450℃, at the same time , the conversion of SO₂ also can reach over 60.0% at 450～500°C and the maximum conversion can reach 67.4%,at the 450℃.At last, the BET and SEM and XRD and FT-IR experiments were carryed out to estimate the selected catalyst's physical and chemical characters. The result of BET shows that the maximum specific surface area of the catalyst is 137.0 m²Â·g^-1.we can conclude that the catalyst has a better specific surface area , which is a foundation for adsorption and iron loaded . The analysis results by XRD and SEM show that the catalyst contains abundant metal elements and carbon , and there are plenty of porous and crystal structures with active particles on its surface and in its holes, which all indicate that this catalyst has a good catalytic activity.