High-performance palladium catalysts for the hydrogenation toward dibenzylbiotinmethylester: Effect of carbon support
Nihong An1, Mengxu Zhang1, Zhihui Zhang2
1State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals, Kunming Institute of Precious Metals, Kunming 650106, China.
Abstract:
Different functionalized carbon materials were used as supports to prepare Pd/carbon catalysts (Pd/AC, Pd/AC-O, Pd/AC-Cl and Pd/AC-N). The results of various characterization techniques revealed that a substantial increase in the surface functional groups of the supports could influence the size of the Pd nanoparticles and the chemical states of the Pd species due to Pd-support interactions. During the hydrogenation reaction to synthesize dibenzylbiotinmethylester, the Pd/AC-N catalyst, based on a support that was treated with nitric acid (AC-N), provided a higher yield of dibenzylbiotinmethylester than the other catalysts. The increase in surface oxygen groups (mainly CO2-releasing groups) in the AC-N support was relevant to achieving selective hydrogenation. These groups can provide an efficient pathway for the reaction, which may be responsible for the high yield of dibenzylbiotinmethylester.
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