Chinese Journal of Chemical Engineering, Vol.28, No.5, 1260-1267, 2020
A bifunctional MnOx@PTFE catalytic membrane for efficient low temperature NOx-SCR and dust removal
Low-temperature selective catalytic reduction of NOx combined with dust removal technique due to its energy conservation characteristic has been attracted much attention for fume purification. In this work, the MnOx wrapped PIPE membrane with efficient dust removal and low-temperature NH3-SCR has been prepared with a facile route. MnOx with different crystal structures was uniformly grown around the PTFE fibrils through water bath. The flower-sphere-like MnOx@PTFE(O-MnOx@PTFE) and lamellar-interlaced ripple-like MnOx@ PTFE(W-MnOx@PTFE) have large specific surface area which is favorable for enhancing catalytic performance. Also, the uniformly wrapped W-MnOx around the PTFE fibrils optimized the pore structure for ultrafine dust capture. The membrane can almost 100% reject particles that are smaller than 1.0 pm with a low filtration resistance. Meanwhile, W-MnOx@PTFE with more surface chemisorbed oxygen has the best NO conversion efficiency of 100% at a comparatively low and wide activity temperature window of 160-210 degrees C, which is far to the thermal limitation of the PTFE. Therefore, this efficient and energy conserving membrane has a bright application prospects for tail gas treatment compared to the original treatment process. (C) 2019 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co.,Ltd. All rights reserved.