The Kinetics of Nickel Sorption on Pyrophyllite as Monitored by X-Ray Absorption Fine Structure (XAFS) Spectroscopy
نویسندگان
چکیده
This study investigated the effect of reaction time (minutes to months) on the surface coordination environment of Ni sorbed onto pyrophyllite using XAFS. The data suggest the appearance of multinuclear Ni complexes after a reaction time of minutes. As reaction time !>rogresses, these multinuclear Ni complexes increased in size «NNi-Ni 1.4-4.5). Ni-Ni bond distances (2.99-3.03 A) were similar to those for mixed Ni-AI hydroxides (3.03 A), but distinctively sboner than those for Ni(OHh(s) (3.09 A). We propose that the formation of mixed Ni-Al hydroxides may explain the observed bond distances and coordination nnmbers.
منابع مشابه
Mechanisms of Nickel Sorption on Pyrophyllite: Macroscopic and Microscopic Approaches
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