Dust filtration influence on the performance of catalytic filters for NOx reduction

Particle matter and NOx emission are the most significant pollutants of combustion processes, particularly so for the conversion of biomass to energy. Currently, reduction of these pollutants is addressed through particle filters and catalytic processes. Therefore, catalytic activation of filter materials seems to be a practical way to reduce NOx and fine particle emission (PM10) simultaneously at small and medium furnaces. Regularly used methods to achieve this rely on the impregnation process. However, alternatives for materials with low wettability are needed. An alternative developed and discussed in this article consists of simultaneous synthesis of filter and catalyst through hard template sintering, where the catalyst is integrated into the porous medium during the fabrication of the filter. This sintering method provides an integrated catalytic filter. Through this method, up to 2% of catalyst loading was achieved in the synthesis of four catalytic filters. The performance of these new catalysts was evaluated under downscale industrial conditions and compared with an ordinary impregnated catalyst. Finally, adust aging treatment was applied on the catalysts in order to see the long-term influence of fine dust particles on the NOx conversion.