COMPOSITION FOR USE AS NOX TRAP, COMBINING TWO COMPOSITIONS BASED ON MANGANESE AND ANOTHER ELEMENT SELECTED AMONG THE ALKALINES, ALKALINE-EARTIES AND RARE EARTHS AND USE THEREOF FOR TREATING EXHAUST GASES

摘要

The invention concerns a compound and its use as NOx trap in the treatment of exhaust gases. Said compound is characterised in that it comprises a combination of: a first composition comprising a support and an active phase, the active phase being based on manganese and at least another element A selected among the alkalines and alkaline earths, the manganese and the element A being chemically bound, a second composition comprising a support and an active phase based on manganese and at least another element B selected among the alkalines, the alkaline-earths and rare earths, said second composition having or capable of having a specific surface area of at least 10 m<2>/g after being calcined for 8 hours at 800 DEG C.