Gold catalysts incipient wetness impregnation

With a view to optimizing the activity and selectivity of the Au/C catalyst, a short screening on deposition and activation methods was carried out. Comparing, in Table 3, three different deposition methods, namely alkaline precipitation (entry 1), absorption from diluted solution of HAUCI4 (entry 2) and incipient wetness impregnation (entry 3), followed by reduction of gold to metal, we observed that the first method performed the best. Although all the methods show... 

Gold catalysts supported on active carbon and alumina have been prepared by incipient wetness impregnation or by precipitation at basic pH using aqueous solutions of HAUCI4 [82]. 

High activity supported gold catalysts by incipient wetness impregnation, M. Bowker, A. Nuhu, and J. Soares, Catal. Today, 2007,122, 245. 

In addition, the catalyst preparation method plays an important role sol immobilization appears superior to incipient wetness or impregnation methods. Gold sol immobilization occurs via citrate reduction of HAuCU, yielding a narrow par-... 

Most of the published methods for preparing gold catalysts in small research quantities are unlikely to prove suitable for commercial applications.1 Complete removal of precious metal from the liquid phase is desirable when using solution methods deposition-precipitation (DP) techniques, whilst producing highly active catalysts, also consume large quantities of water and the cost of treatment of wastewater is an expensive additional process. Other preparation methods such as appropriate modifications of impregnation via incipient wetness techniques are more likely to be suitable for commercial production if they lead to reproducible, stable... 

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]. 

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