The Cu I Y, Ce IV Y, and Cu I Ce IV Y zeolites were successfully prepared and the competive adsorptions of toluene, cyclohexene, and pyridine were investigated. The results indicate that the effects on the metal ion-exchanged Y zeolites for sulfur removal decrease in the order pyridine > cyclohexene > toluene. The Cu I Ce IV Y not only has high sulfur adsorption capacity, similar to Cu I Y, but also has high selectivity for sulfur compounds, similar to Ce IV Y. The isotherms and kinetics of benzothiophene (BT) adsorption from 1-octane onto Cu I Ce IV Y were studied, and the thermodynamic parameters (ΔG, ΔH, ΔS) for the adsorption of BT were calculated. The results show that the isothermal equilibrium can be represented by the Langmuir model and that maximum adsorption capacities (q m ) increase with an increase of temperature. The kinetics for the adsorption process can be described by either the Langmuir model or a pseudo-first-order model. The adsorption is spontaneous and exothermic.

No abstract

A bimetal-exchanged NaY zeolite (Cu(I)-Y(III)-Y) with a desirable adsorptive desulfurization (ADS) performance was prepared and characterized by means of X-ray diffraction, specific surface area measurements, X-ray fluorescence spectrometer, X-ray photoelectron spectroscopy, thermal gravity analysis and Fourier transform infrared spectroscopy. The effect of Y(III) ions on ADS in the presence of the xylenes was investigated. Results indicated that the ADS performance of Y(III)-Y is higher than that of most reported CeY. The Y(III)-based Cu(I)-Y(III)-Y demonstrated the higher breakthrough loading than those of reported Ce(III)/Ce(IV)-based transition metal Y zeolites, showing that Y(III) ions play a promoting role in improving the ADS selectivity. For Cu(I)-Y(III)-Y, a new strong S-M interaction (S stands for sulfur, while M stands for metal) active site was formed, which might be caused by the synergistic effect between Cu(I) and Y(III). The Cu(I)-Y(III)-Y, which combined the advantages of Cu(I)-Y and Y(III)-Y, is a kind of promising adsorbent. The breakthrough loading decreased in the order of Cu(I)-Y(III)-Y > Y(III)-Y > Cu(I)-Y, and the effect of xylene isomers on the sulfur removal was in the order of ortho-xylene > meta-xylene > para-xylene, which exhibited the same trend with the bond order of xylenes.