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Updated: May 27, 2026

Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area
Published on: February 19, 2018
Studies on the dehydration of glycerol over niobium catalysts
Young Yi Lee1, Dong Ju Moon, Jong Ho Kim
1Department of Advanced Chemicals and Engineering and Center for Functional Nano Fine Chemicals, Chonnam National University, Gwangju 500-757, Korea.
Abstract:
The dehydration of glycerol over nanosize niobium catalysts was conducted in a stainless steel autoclave reactor. The catalysts were prepared by the calcination of niobium oxalate between 200 and 700 degrees C. Catalysts were characterized by N2 Physisorption, XRD and TPD of ammonia to investigate the effect of the calcination temperature and water on catalytic performance, catalysts' structures and acidity. Acrolein was mainly produced about 51-71% with useful by-products such as acetaldehyde and methanol. Amorphous Nb2O5 catalysts calcined at 200-400 degrees C significantly showed higher conversion of glycerol than the crystallized Nb2O5 catalyst calcined at 500-700 degrees C. Also the conversion of glycerol and selectivity of acrolein was increased with increasing the acidity of catalyst, which can be controlled by calcination temperature.
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