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Indexed by:期刊论文

Date of Publication:2012-07-01

Journal:JOURNAL OF NATURAL GAS CHEMISTRY

Included Journals:SCIE、EI、ISTIC、CSCD

Volume:21

Issue:4

Page Number:421-425

ISSN No.:1003-9953

Key Words:toluene; Ce(IV)Y; adsorption desulfurization; thiophene; Ce4+-S interaction

Abstract:Zeolites NaY and Ce(IV)Y were employed as adsorbents to remove organic sulfur compounds from model gasoline (MG) solutions with and without toluene in static adsorption experiments at room temperature (RT) and atmospheric pressure. The adsorbents were characterized by XRD, XRF and pyridine infrared spectrum (R). The adsorption experiments show that the desulfurization performance of Ce(IV)Y is much better than that of NaY. The sulfur removal over both NaY and Ce(IV)Y decreases with the increase of toluene concentration in MG, however, the decline tendency on Ce(IV)Y is smooth, and it is steep on NaY. FT-IR spectra of thiophene adsorption indicate that thiophene molecules are mainly adsorbed on NaY via pi electron interaction, but on Ce(IV)Y, in addition to the pi electron interaction, both Ce4+-S direct interaction and protonation of thiophene also play important roles. Toluene molecules are adsorbed on NaY also via it electron interaction. Although the amount of Bronsted acid sites is increased due to the introduction of Ce4+ ions into NaY zeolite, it is not found to influence the adsorption mode of toluene over Ce(IV)Y. Compared with NaY zeolite, the improved desulfurization performance over Ce(IV)Y for removing organic sulfur compounds from MG solution, especially those containing large amount of aromatics, may be ascribed to the direct Ce(IV)-S interaction, which is much resistant to the influence resulted from toluene adsorption.