Impregnated and co-precipitated, promoted and unpromoted, bulk and supported iron catalysts were prepared, characterized, and subjected to hydrogenation of CO 2 at various pressures (1-2 MPa) and temperatures (573-673 K). Potassium, as an important promoter, enhanced the CO 2 uptake and selectivity towards olefins and long-chain hydrocarbons. Al 2 O 3 , when added as a structural promoter during co-precipitation, increased CO 2 conversion as well as selectivity to C 2? hydrocarbons.

A series of Cu-ZnO catalysts with varying Cu to Zn weight ratio are prepared by co-precipitation method. The catalysts were characterized by surface area, XRD, TPR and N 2 O chemisorption to measure Cu metal area. These catalysts were evaluated for hydrogenolysis of glycerol. The catalyst with Cu to Zn ratio of 50:50 is highly active under relatively low H 2 pressure. The catalysts are highly selective towards 1,2 propanediol ([93%). The glycerol conversion depends upon the bifunctional nature of catalyst where it requires both acidic sites and metal surface. The presence of sufficient amount with small particle size of ZnO and Cu are required for high conversion of glycerol and selectivity to 1,2 propanediol. Different reaction parameters are studied in order to optimize the reaction conditions.

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Selective hydrogenolysis of glycerol to 1,2-propanediol over Cu-MgO catalysts is reported. A series of Cu-MgO catalysts with varying Cu content were prepared by a co-precipitation method. The physico-chemical properties of the catalysts were derived from BET surface area, X-ray diffraction, temperature programmed reduction of hydrogen, temperature programmed desorption of carbon dioxide, X-ray photoelectron spectroscopy, transmission electron microscopy and dissociative N 2 O adsorption techniques. The activity results showed that Cu content on MgO has a significant role in glycerol conversion as well as formation of 1,2-propanediol. Well dispersed Cu species and accessible basic sites of MgO are the essential requirements for high glycerol hydrogenolysis activity. 20 wt% of Cu content on MgO is identified as an optimum Cu content. The catalyst is equally active even with crude glycerol and glycerol containing alkali salts as impurity. Different reaction parameters were evaluated and optimized reaction conditions were established.

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