Porous TiO2 aerogel-modified SiC ceramic membrane supported MnOx catalyst for simultaneous removal of NO and dust

Abstract

As the main atmospheric pollutants, the nitrogen oxides (NOx) and dust from industrial exhaust have caused a series of environmental problems. Catalytic membrane is one of the most important technologies for integrated denitration and dust removal, which can achieve the efficient treatment of multiple pollutants. In order to achieve the simultaneous removal of NO and dust in low-temperature exhaust, a novel MnOx/TiO2/SiC catalytic membrane was developed. The using of TiO2 aerogel as the transition layer could increase the loading capacity of MnOx by more than twice, but has little effect on gas permeance of SiC ceramic membrane. The MnOx/TiO2/SiC catalytic membrane also exhibit excellent filtration performance with dust rejection rate exceeding 99.97% and thus preventing adverse effects of dust on the catalyst. In the NO and dust coexistence system, the obtained catalytic membrane exhibits good catalytic activity owing to its high loading capacity and outstanding filtration performance, which lead to the high NO conversion rate above 80% with the temperature range of 120–180 °C. Meanwhile, the catalytic membrane exhibits remarkable stability in simulation environment, and the NO conversion rate could maintain at 90% within 65 h. The novel MnOx/TiO2/SiC catalytic membrane showed great promise for low-temperature exhaust gas purification.