title: Mechanistic study on adsorptive removal of tert-butanethiol on Ag-Y zeolite under ambient conditions.
abstract: The dynamics and surface chemistry of tert-butanethiol (TBT) adsorptive removal over silver-exchanged Y zeolite (Ag-Y) were studied under ambient conditions. Saturation uptake on Ag-Y was higher than that on H-Y and Na-Y. The structural analyses by a combination of X-ray diffraction, Ag K-edge X-ray absorption near-edge structure (XANES)/extended X-ray absorption fine structures (EXAFS), Ag L(III)-edge XANES, S K-edge XANES, and in situ UV-vis show that the AgSH molecule, Ag(2)S monomer, and Ag(4)S(2) cluster are the dominant silver species in TBT-saturated Ag-Y. Dynamic changes in adsorbed intermediates, gas-phase products, and the silver sulfides were followed by in situ FTIR, mass spectroscopy and in situ UV-vis, respectively. The results show the following reaction mechanism: (1) formation of iso-butene and adsorbed H(2)S on the Ag(+) site via C-S cleavage of hydrogen-bonded TBT initially adsorbed on the Ag(+) site; (2) conversion of the adsorbed H(2)S to AgSH and H(+) on zeolite; (3) the reaction of two Ag-SH species to yield Ag(2)S and H(+) on zeolite.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan. kshimizu@apchem.nagoya-u.ac.jp
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Shimizu
authors.forename: Nobumitsu
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Satsuma
authors.forename: Toshinori
authors.initials: T
authors.lastname: Kojima
authors.forename: Shigeo
authors.initials: S
authors.lastname: Satokawa