Preparation of pyrolytic carbon-based denitrification catalyst modified by Mn and its low-temperature denitrification performance
In this study,two kinds of biochar were prepared by pyrolysis and carbonization using walnut shell as the starting materials,and then subjected to KOH activation and the sequential Mn-modification to prepare Mn modifying carbon-based denitrification catalyst.The effects of preparation methods of biochar and activation temperature on the physicochemical properties and denitrification performance of the catalysts were investigated by multiple techniques such as physical adsorption.The results showed that compared to the Mn modifying carbonized carbon-based denitrification catalyst,the Mn modifying pyrolytic carbon-based denitrification catalyst possessed larger specific surface area,well-developed pore structure,higher Mn4+content,and thus better low-temperature denitrification performance.When the space velocity was 20000h-1 and the denitrification temperature was 120℃,the denitrification efficiency and N2 selectivity of the Mn modifying pyrolytic carbon-based catalyst reached 87.2%and 98.1%,respectively,and the denitrification efficiency maintained 85.1%after continuous reaction for 10h.And the denitrification efficiency increased to 95.1%at denitrification temperature of 180℃,much higher than that of the Mn modifying carbonized carbon-based denitrification catalyst(86.4%).The catalysts produced at too high or too low activation temperature showed diminished denitrification performance,and those prepared at activation temperatures of 700℃ and 900℃ had denitrification efficiencies of 80.5%and 87.9%at denitrification temperature of 180℃,respectively.This study provided a new strategy for the high-value utilization of pyrolytic carbon and achieved efficient removal of MnOx,which was of great significance for the fulfilment of the carbon peak and carbon neutrality goal and environmental protection.
国家科技期刊平台
NSTL
万方数据
