Open AccessIn situ observation of Ni–Mo–S phase formed on NiMo/Al 2 O 3 catalyst sulfided at high pressure by means of Ni and Mo K ‐edge EXAFS spectroscopy
Author(s) -
Koizumi Naoto,
Hamabe Yusuke,
Jung Sungbong,
Suzuki Yasuhiro,
Yoshida Shohei,
Yamada Muneyoshi
Publication year - 2010
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049510004802
Subject(s) - hydrodesulfurization , extended x ray absorption fine structure , catalysis , molybdenum , phase (matter) , analytical chemistry (journal) , nickel , materials science , k edge , atmospheric pressure , chemistry , crystallography , absorption spectroscopy , metallurgy , biochemistry , physics , oceanography , organic chemistry , chromatography , quantum mechanics , geology
To obtain direct evidence of the formation of the Ni–Mo–S phase on NiMo/Al 2 O 3 catalysts under high‐pressure hydrodesulfurization conditions, a high‐pressure EXAFS chamber has been constructed and used to investigate the coordination structure of Ni and Mo species on the catalysts sulfided at high pressure. The high‐pressure chamber was designed to have a low dead volume and was equipped with polybenzimidazole X‐ray windows. Ni K ‐edge k 3 χ( k ) spectra with high signal‐to‐noise ratio were obtained using this high‐pressure chamber for the NiMo/Al 2 O 3 catalyst sulfided at 613 K and 1.1 MPa over a wide k range (39.5–146 nm −1 ). The formation of Ni–Mo and Mo–Ni coordination shells was successfully proved by Ni and Mo K ‐edge EXAFS measurement using this chamber. Interatomic distances of these coordination shells were almost identical to those calculated from Ni K ‐edge EXAFS of NiMo/C catalysts sulfided at atmospheric pressure. These results support the hypothesis that the Ni–Mo–S phase is formed on the Al 2 O 3 ‐supported NiMo catalyst sulfided under high‐pressure hydrodesulfurization conditions.