Catalytic reduction of NO by CO with Cu-based and Mn-based catalysts

Various Cu-based and Mn-based catalysts are prepared and evaluated for the reduction of NO with CO process. Cu-Ce-Fe-Co/TiO2 and Mn-Ce-Fe-Co/TiO2 show the best catalytic performance for the reduction of NO with CO process among Cu-based and Mn-based catalysts, respectively. The highest conversions of NO and CO achieved with Cu-Ce-Fe-Co/TiO2 reach 100% and 79%, respectively, with the operating temperature of 250 degrees C, while 100% and 70% are achieved with Mn-Ce-Fe-Co/TiO2 for the gas streams containing 200 ppm NO and 200 ppm CO. The results reveal that both modified catalysts (e.g., Cu-Ce-Fe-Co/TiO2 and Mn-Ce-Fe-Co/TiO2) have good activities for CO+ NO reaction. Overall, Cu-Ce-Fe-Co/TiO2 has better tolerance for O-2, SO2 and H2O(g) than MnCe-Fe-Co/TiO2. Good catalytic performance of Cu-Ce-Fe-Co/TiO2 toward NO reduction is attributed to its good surface properties, i.e., reducibility, oxygen mobility and more oxygen vacancies. Additionally, the apparent activation energy is calculated as 54.2 kJ/mol is calculated using Mars-Van Krevelen model for reduction of NO with CO process with Cu-Ce-Fe-Co/TiO2 as catalyst. Further, active component Cu-Ce-Fe-Co is loaded on activated carbon (AC) to form Cu-Ce-Fe-Co/AC, which is applied as catalyst for durability test. The results indicate that NO conversion achieved with Cu-Ce-Fe-Co/AC maintains at 100% during 240 min operation period, even in the simultaneous presence of O-2, H2O(g) and SO2. Overall, this study demonstrates that Cu-based catalyst is promising for the reduction of NO with CO process.