Chromium, Molybdenum and Tungsten Catalysts

The M(C0)6 (M = Cr, Mo, W) stable carbonyls have been used to prepare metal supported catalysts of elements of group 6 that have been used as catalysts in several reactions, such as metathesis, water-gas shift, CO hydrogenation and olefin hydrogenation and polymerization [15-24]. Table 8.2 compiles several examples in which M(CO)s (M = Cr, Mo, W) compounds are used as an alternative for preparing chromium-molybdenum or tungsten-based catalysts. 

The characteristics of the hexacarbonyls of these elements allow the preparation of catalysts by their vapor phase adsorption onto the support. Studies of the 

Carbonyl Support Preparation method Catalyst characteristics Reference 

Cr CO)e MCM-41 UV-irradiated and ultrasound treated anchoring Highly dispersed species, high activity in ethylene polymerization [23, 24] 

Mo(CO)6 and Co(CO)3NO NaY zeolite Adsorption from vapor phase and H2S treatment Intrazeolite Co2Mo2S i clusters, model hydrodesulfuration catalyst [25] 

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