Copper, Cobalt And Manganese: Modified Hydrotalcite Cross Mark Materials As Catalysts For The Selective Catalytic Reduction Of No With Ammonia. The Influence Of Manganese Concentration

Hydrotalcites containing Cu, Co and Mn with varying manganese contents were prepared by co-precipitation. Manganese was also introduced into the catalysts via adsorption of an Mn-EDTA complex from an aqueous solution. The obtained samples were characterized by room- and high-temperature XRD, low-temperature nitrogen sorption, and Fr-IR. Calcination of the catalysts at 500 degrees C resulted in the formation of mixed oxides with specific surface areas of 166-187 m(2)/g. The calcined samples were tested as catalysts for selective catalytic reduction of NOx with ammonia. It was found that the Mn content strongly influences the product selectivity in SCR-NH3. Mn-EDTA modified samples exhibited higher selectivity towards N-2 than Mn hydrotalcites obtained by the co-precipitation method. A hydrotalcite sample containing 5.4 wt% of manganese showed the highest catalytic activity and the lowest selectivity to N-2 at the same time. (C) 2015 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.