摘要

Two carbon xerogels (CX) with different pore size distributions were prepared by the conventional approach (condensation of resorcinol and formaldehyde). The key variable to control those sizes is the pH of the aqueous solution. Gold nanoparticles were supported on the prepared CXs by the sol immobilization method and tested in the selective oxidation of glycerol, with the main purpose of evaluating the influence of the textural properties on the activity and selectivity. Mesopore sizes of the support have a strong effect on the distribution of products: wide pores enhance the formation of dihydroxyacetone whereas narrow mesopores favor the oxidation towards glyceric acid. Additionally, the selectivity results obtained with carbon xerogels were compared with those achieved with other carbon supports (activated carbon and multi-walled carbon nanotubes) and the same trend was observed. Therefore, it seems that the distribution of products can be controlled by the adequate choice of the support. For this purpose, carbon xerogel is a promising material since its pore size can be easily modified in a controllable way during the preparation stage.

  • 出版日期2012-4-5