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Indexed by:期刊论文

Date of Publication:2014-07-01

Journal:CATALYSIS LETTERS

Included Journals:SCIE、EI

Volume:144

Issue:7

Page Number:1118-1126

ISSN No.:1011-372X

Key Words:Raney Ni-Si; Silicification; 2-Butyne-1,4-diol; Selective hydrogenation

Abstract:Raney Ni-Si catalysts were synthesized by treating Raney Ni with silane in a fluidized bed reactor and tested in the selective hydrogenation of 2-butyne-1,4-diol (BYD) at high concentration. Structural characterizations including XRD patterns, TEM images, and X-ray photoelectron spectroscopy show that Raney Ni-Si catalysts are composed of a Ni core surrounded by nickel silicides. These species transform from Ni-rich silicide (Ni2Si) to Si-rich silicide (NiSi2) with increasing silicification temperature from 250 A degrees C to 450 A degrees C. The insertion of Si atoms into Raney Ni catalysts decreased the catalytic activity, but significantly improved the selectivity to 2-butene-1,4-diol (BED). The beneficial effect of Si on the selectivity hydrogenation of BYD may be caused by the presence of Si at Ni-defect sites, and the formation of the surface nickel silicide that suppress the further hydrogenation of BED. Compared with the traditional Lindlar-type catalysts, such Raney Ni-Si materials can be used extensively in organic synthesis for selective hydrogenation of alkynes, avoiding the associated hazards of toxic additives.
   Raney Ni-Si catalysts, synthesized by treating Raney Ni with silane, showed that the insertion of Si atoms into Raney Ni catalysts decreased the catalytic activity, but significantly improved the selectivity to 2-butene-1,4-diol.