SELECTIVE SURFACE IMPREGNATION METHOD FOR CATALYTIC MATERIAL WITH THE REPULSIVE FORCE BETWEEN HYDROPHILIC AND HYDROPHOBIC SOLVENTS AND CATALYST MADE THEREOF

摘要

The present invention relates to a method for preparing a catalyst in which a catalytically active material is selectively supported or impregnated only on a surface of a catalyst particle by using mutual repulsion of a hydrophobic solvent and a hydrophilic solvent, and a solubility difference of the hydrophobic solvent and the hydrophilic solvent with respect to a metal salt precursor, and in which C3-C6 alcohols, such as propanol, butanol, pentanol, hexanol are used as the hydrophobic solvent. A catalytically active material or a precursor preparing a catalytically active material selectively supported or impregnated on only outside of a catalyst particle by: introducing the hydrophobic solvent to a catalyst support; drying the resultant under an appropriate condition; removing the hydrophobic solvent from some pores connected to outside of a catalyst particle; the hydrophilic solution occupies an empty space in which the hydrophobic solvent has disappeared by introducing a hydrophilic solution including a metal salt; and drying the resultant at a slow rate. Through this method, it is possible to prepare an egg-shell type catalyst in which a catalytically active material supported or impregnated only on an outside region of a catalyst particle.