Few examples of the characterisation by FTIR spectroscopy supplemented by t
he use of CO2, CO and NO molecular probes of acid, base and redox centres i
n zeolites (NaX and NaY) and zeolite-type (HSAPO-34, a silicon-aluminophosp
hate: and CoAPO-18, a cobalt-aluminophosphate) catalysts, are illustrated.