Abstract: Industrial high-temperature flue gas often contains trace amounts of SO_○x and is weakly acidic. During denitrification treatment， ammonia escape will make it slightly alkaline with fluctuation， which will cause acid-base interactive corrosion of bag-type dust filter material， resulting in the failure of filter bag. In order to explore the effect of acid-base interaction corrosion on the filtration performance of the filter material， the mechanical properties， surface morphology， chemical composition and filtration performance of the aramid filter with different experimental treatment methods were studied. The results show that 20% NaOH solution and 35% H₂SO₄ solution are secondary interactively corroded. The strength retention rates of warp and zonal are 53.76%， 41.26%， respectively. The elongation retention rate at break are 40.23%， 63.69%， respectively. The thickness is increased by 6.55% and the surface density is decreased by 5.18%. After treatment， the fiber surface becomes rough， with longitudinal grooves and transverse cracks. The essential reason for the damage caused by acid-base interaction corrosion on the performance of aramid filter is that the amide group in the filter is destroyed， so that the macromolecular chain is broken， and the degree of damage varies with the mass fraction of acid and alkali in the solution and the change in the order of acid-base corrosion.

Key words: filter; acid-base interaction corrosion; mechanical behavior; infrared spectrum; filtration performance