Catalysts Concepts Guiding Choice and Design

1 Metal Catalysts Concepts Guiding Choice and Design 

For industrial applications, metal catalysts should be repeatedly recycled or used in continuous mode for a long time. The introduction of gold catalysis in the aerobic oxidation of glucose has opened exciting perspectives Au is a biocompatible, nontoxic metal, which allows even superior productivities with respect to enzymatic catalysis [38], and no leaching problems have been observed using nanometric particles dispersed on different supports [43]. Compared with chemical oxidations, enzymatic catalysis suffers from more plant complexities 

Several methods are available for preparing supported metal catalysts. Commonly used methods include impregnation to incipient wetness, deposition-precipitation (DP), coprecipitation, and deposition/immobilization of colloidal metals. A useful description of such techniques is reported for gold catalysts [43]. 

Coprecipitation is applied to support the noble metal to the in sitM-prepared oxidic material, such as Fe20g, C03O4, NiO, AI2O3, and others. In the case of gold, coprecipitation with Fe20g can be performed by addition of sodium carbonate to a solution containing HAuCl and FefNOjlj, followed by noble metal reduction [46]. 

With this technique, the preparation of bimetalhc systems (e.g., Au—Pd, Au—Pt, 

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