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Preparation of Supported Bimetallic Catalysts Containing Gold

Preparation of Supported Bimetallic Catalysts Containing Gold [Pg.105]

The preparation of a successful supported bimetallic catalyst is quite a difficult proposition. The main problem is to ensure that the two components reside in the same particle in the finished catalyst, and to know that it is so. The main physical techniques to characterise bimetallic particles are hydrogen chemisorption, XRD, TEM, EDX, XPS, XAFS,197Au Mossbauer (Section 3.3) and CO chemisorption coupled by IR spectroscopy (Section 5.3). The characterisation of bimetallic catalysts is not always thoroughly done, and there is the further complication of structural changes (particularly of the surface) during use. In situ or post-operative characterisation would reveal them, but it is rarely done. [Pg.105]

The now classical methods used for the preparation of supported gold catalysts are hardly capable of giving particles that are both small and bimetallic, when the precursors in solution do not interact strongly with each other. During the subsequent thermal treatment performed to get metal particles, the metals must have enough mobility to migrate on the support, interact with each other, and form bimetallic particles. However, phase separation can be a common problem, especially when the metal ratio falls in the miscibility gap (Section 2.6), or if the intended composition is not thermodynamically stable. [Pg.105]

The methods used for preparing gold-containing bimetallic catalysts may be divided into three main classes (i) the methods that do not involve interaction between the two metal precursors in solution (Section 4.6.2) (ii) those that involve sequences of surface reactions designed to create [Pg.105]




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Bimetallic catalysts

Bimetallic catalysts preparation

Catalysts preparation

Catalysts supported, preparation

Gold catalysts

Gold catalysts, supported catalyst preparation

Gold-Containing Bimetallic Catalysts

Preparation of Supported Gold Catalysts

Preparation of catalyst supports

Preparation of supports

Support preparation

Supported bimetallic catalysts

Supported bimetallic catalysts preparation

Supported gold

Supported gold-containing bimetallic

Supported gold-containing bimetallic catalysts

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