Investigations of nitric oxide and carbon monoxide adsorption on the new generation cerium exchanged silico-aluminophosphate of type 18 catalyst

Cerium exchanged SAPO-18 material showed adsorptivity for NO and CO molecul es. In situ adsorption of nitric oxide and carbon monoxide on cerium exchan ged SAPO-18 materials was studied by FT-IR spectroscopy. The cerium exchang ed SAPO-18 samples were prepared using the highly crystalline and pure H-SA PO-18 material. The SAPO-18 and cerium exchanged SAPO-18 materials were cha racterised by routine and sophisticated instrumental techniques. The presen ce of both Ce-III and Ce-IV species on the surface of the Ce-SAPO-18 cataly st were revealed by the XPS technique. The concentration of cerium is highe r on the surface of the material than in the bulk. The interaction of NO wi th Ce-SAPO-18 material led to the formation of nitrous oxide, mono- and di- nitrosyl complexes of cerium, nitrogen dioxide and nitrate species. The for mation of mono-, di- and tri-carbonyl complexes of cerium and carbon dioxid e species were observed after the carbon monoxide adsorption on the Ce-SAPO -18. (C) 2001 Elsevier Science B.V. All rights reserved.