The mechanism for NO(x) storage

The mechanisms for storing of NO(x) in platinum-barium-alumina catalysts during lean-rich transients are investigated. Oxidation of NO to NO(2) is found to be an important step. NO(2) is found to be important for oxidation of the catalyst or of nitrites to form nitrates. NO(x) is then stored in the form of surface nitrates. FTIR studies show no formation of bulk nitrates in these experiments.