Study On Preparation And Support Catalyst Of MX-Filter ACF

Nomex (MX) needle filter fibers are widely used in dust removal in high-temperature flue gas and exhaust gas purification in kinds of industrial furnace of cement, metallurgy and road making in industrial circle because of their high intensity, high modulus and good properties of high temperature, acid and alkaline resistance. But they would be easily broken since operating in high temperature load at a long time, which made waste. With the speeding up of the foot of industrialization, there is lots of needle filter waste produced in the world. So it is significant to utilize the waste rationally. In this paper, we would prepare activated carbon fiber from waste MX needle filter, and use it in NO removal. The main research contents are as follows:Using the waste MX needle filter as precursor, a series of MX-Filter activated carbon fibers were prepared by chemical activation using KOH as activator after the preprocessing and high-temperature carbonization stages. The chemical component of products in the three stages and the pyrolysis process were measured by using element analysis and thermogravimetry methods, respectively. Effects of activation parameters such as activation temperature, activation time and activation ratio on BET surface area and yield of MX-Filter ACF were investigated. Results suggested that high BET surface area (2493.719m2/g) and good yield (52.545%) were obtained in ACF which was prepared under activation condition such as 800℃,60 min and 4:1. And properties of surface adsorption and pore structure of the products obtained under different conditions were characterized by low temperature N2 adsorption-desorption method. The results showed that N2 adsorption-desorption isotherms curves of all the samples are type Ⅰ according to IUPAC, it revealed that the pores in MX-Filter ACF prepared were major micropores. Also the morphology features and phase structure of some samples were characterized by FE-SEM and XRD methods, respectively.A series of MnOx/ACF and Mn-Fe/ACF catalysts were synthesis by an incipient impregnation method using MX-Filter ACF prepared previously as the carrier and oxides of manganese and ferric as active components, and their low-temperature selective catalytic reduction (SCR) denitration efficiency were studied. Effects of different reaction temperature, metal-oxide loadings and molar ratio of manganese and ferric on activity of the catalysts were also studied. The structure, morphology and stability of catalysts were characterized by BET, XRD, FE-SEM, EDS and TG methods. High catalytic activity in low temperature was obtained when the loading of metal-oxide was 1.2%. And 1.2%MnOx/ACF catalyst exhibited a denitration efficiency of 83.5% in 200℃, with addition of a small amount of ferric oxide to 1.2% MnOx/ACF catalyst, the denitration efficiency reached over 92%. The result displayed that moderate ferric oxide would benefit to improving catalytic activity of the 1.2% MnOx/ACF catalyst.