Fourier transform-infrared photoacoustic spectroscopy (F-F IR/PAS) and X-ray diffraction
(XRD) techniques have been used to study the reduction of copper (11) oxide supported on
mordenite zeolite, through the adsorption of carbon monoxide and hydrogen gases at 723 K.
It was found that bands due to the bridged hydroxyl groups (3614-3630 cm-1) and the AI-OH
groups (3780-3787 cm-1) show significant changes upon carbon monoxide and hydrogen
adsorption whereas the Si-OH band did not change after the adsorption. Two further bands
were detected at 2156 and 2297 cm -1, assigned to carbon monoxide adsorbed on Cu §
species and on the copper-aluminate species, respectively. XRD patterns have
demonstrated the proposed interaction between Cu 2§ with aluminium mordenite, to form
aluminate, whereas FT-IR spectra have established an interaction between carbon
monoxide molecules and the aluminate species.