Ethylene Adsorption on Alkali-Hydrophobic Zeolite Y

Zeolites HY with different hydrophobicity having Si/Al ratios of 10, 100 and 750 were modified by an ion exchange process with nitrate solutions of alkali cations in the concentration range 0.1 - 100 mM. The modified samples were characterized by ICP-OES, XRD and surface analysis with N2-adsorption. The ethylene adsorptivities of these modified zeolites were measured under degassed and non-degassed conditions. All zeolites showed the enhancement in ethylene adsorptivity upon modification, while the K+ ions modified ones showed the best enhancement. The modified hydrophobic zeolites with Si/Al ratios of 100 and 750 showed no differences in adsorptivity under the degassed and non-degassed conditions. However, for less hydrophobic zeolite (Si/Al = 10), the adsorption under the degassed condition was much higher than the adsorption under the non-degassed condition. These results indicate that the modified hydrophobic zeolites with Si/Al ratios of 100 and 750 are suitable as ethylene scavengers at ambient conditions. HIGHLIGHTS Zeolites Y with different Si/Al ratios were modified by alkali nitrate solutions The ethylene adsorptivities were measured under degassed and non-degassed conditions Zeolites showed better ethylene adsorptivity upon modification with alkali cation K+ ions modified zeolite showed the best enhancement Modified zeolites (100 and 750) suited as ethylene adsorbent at ambient conditions GRAPHICAL ABSTRACT