Exchanged zeolites with transition metals of the first period as photocatalyts for n-hexadecane degradation

The photodegradation of n-hexadecane (n-C16) was tested using photocatalysts containing MOR, ZSM-5 or Y zeolites exchanged with ∼5.2 wt% of V, Cr, Mn, Cu or Zn. n-C16 was selected to realize intimate contact to the metal cations inside the zeolitic channels. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) indicated retaining high crystallinity of the catalysts incorporating the current metals. Moreover, the UV–vis spectra indicated that the current-exchanged metals are present as isolated species. Application of the Langmuir–Hinshelwood kinetics admitted calculating the photocatalytic degradation rate constant, k, and the adsorption coefficient, Kad, for the photodegradation of n-hexadecane, which have been found to correlate with atomic weights of the metals and their active cationic surface area. The MOR containing catalysts exhibited a reversed behaviour of k and Kad, compared to those containing ZSM-5 and Y zeolites. However, Kad seems to be correlated well with the active surface area of the metal cations.

Graphical abstractThe photodegradation of n-hexadecane (n-C16) was tested using photocatalysts containing MOR, ZSM-5 or Y zeolites exchanged with ∼5.2 wt% V, Cr, Mn, Cu or Zn. Spectra examinations indicated retaining high crystallinity and the current-exchanged metals are present as isolated species. The photocatalytic degradation rate constant, k, and the adsorption coefficient, Kad, were found to correlate with the metals atomic weights and their active cationic surface area. Figure optionsDownload full-size imageDownload as PowerPoint slide