Chen Gao
Xi’an Jiaotong University, China
Title: Title: Ho2O3-modified MnOx-TiO2 catalyst for SCR De-NOx with N
Biography
Biography: Chen Gao
Abstract
Nitrogen oxides (NOx) emission from the combustion of fossil fuels and biomasses is a major global environmental issue. It contributes to acid rain, formation of ground level ozone and yellow smog, which could lead to serious damages to human health and our ecosystem. The selective catalytic reduction (SCR) has been proved to be one of the most effective methods for post combustion denitration (de-NOx). It converts NOx in flue gases to harmless N2 and H2O. Among many low-temperature catalysts reported in the literature, manganese oxide (MnOx) has been proved highly active at low temperature between 75 oC and 225 oC. However, single MnOx catalysts are unstable, easy to be poisoned and deactivated by SO2 and their operation temperature window is narrow. To overcome the drawbacks of pure MnOx, we modified the TiO2 supported MnOx (MnOx-TiO2) by using small amount of holmium oxide (Ho2O3). The obtained catalyst exhibited a wide operating temperature window with a 100% NOx conversion activity from 150 to 390 oC and a 100% N2 selectivity from 150 to 360 oC under a high space velocity of 36,000 h-1. The high efficiency is attributed to structural and electronic changes induced by Ho2O3 modification. Additionally, Ho2O3 modification promotes the stability of MnOx-TiO2 catalyst against SO2 poison, especially SO2 poison under concurrent H2O vapor influence.