In situ decorated Mn-FeOx amorphous oxides on filter felt by a polyphenol-assisted method for low-temperature NH3-SCR

The combination of dust filtration technology and selective catalytic reduction of nitrogen oxides can effectively reduce the energy consumption and footprint of the flue gas purification system. To fabricate the high efficiency and firmly bonded catalytic filter material, a novel polyphenol-assisted method was designed in this work for in situ decorating Mn-FeO_x amorphous oxides onto the smooth polyphenylene sulfide (PPS) filter felt. The polyphenolic compounds are not only worked as the dispersant, but also the binder for Mn-FeO_x catalysts to firmly anchor on PPS filter felts. The introduction of Fe³⁺ into catalyst precursors can increase the Mn⁴⁺ content, surface adsorbed oxygen, as well as surface acidity, which displays satisfactory denitration performance and SO₂ tolerance at low temperatures. The Mn₅Fe₁-TA/PDA@PPS sample shows nearly 100 % NO conversion efficiency at 180 °C with only 10.11 % catalysts loading in the sulfur dioxide free flue gas. Furthermore, the green and efficient synthesis route makes the catalytic filter felts preserve the same gas permeability and thermal stability with the pristine PPS filter felt, which suggests that the Mn₅Fe₁-TA/PDA@PPS has great prospects for simultaneously removing of NO_x and dust in practical applications.