A catalyst comprising chromia and at least one additional metal or compound thereof and wherein the catalyst has a total pore volume of greater than 0.3 cm.sup.3/g and the mean pore diameter is greater than or equal to 90 Å, wherein the total pore volume is measured by N2 adsorption porosimetry and the mean pore diameter is measured by N.sub.2 BET adsorption porosimetry, and wherein the at least one additional metal is selected from Li, Na, K, Ca, Mg, Cs, Sc, Al, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Co, Rh, Ir, Ni, Pd, In, Pt, Cu, Ag, Au, Zn, La, Ce and mixtures thereof.

A method for preparing C.sub.2 to C.sub.5 paraffins including introducing a feed stream of hydrogen gas and a carbon-containing gas selected from carbon monoxide, carbon dioxide, and mixtures thereof into a reaction zone of a reactor. Converting the feed stream into a product stream that includes C.sub.2 to C.sub.5 paraffins in the reaction zone in the presence of a hybrid catalyst. The hybrid catalyst including a microporous catalyst component; and a metal oxide catalyst component. The metal oxide catalyst component including a metal component present on a metal oxide support material. The metal oxide support material includes at least one oxide of a metal selected from Group 4 of the IUPAC periodic table of elements. The product stream has a C.sub.3/C.sub.2 carbon molar ratio greater than or equal to 4.0.

A method for preparing C.sub.2 to C.sub.5 paraffins including introducing a feed stream of hydrogen gas and a carbon-containing gas selected from carbon monoxide, carbon dioxide, and mixtures thereof into a reaction zone of a reactor. Converting the feed stream into a product stream that includes C.sub.2 to C.sub.5 paraffins in the reaction zone in the presence of a hybrid catalyst. The hybrid catalyst including a microporous catalyst component; and a metal oxide catalyst component. The metal oxide catalyst component including a metal component present on a metal oxide support material. The metal oxide support material includes at least one oxide of a metal selected from Group 4 of the IUPAC periodic table of elements. The product stream has a C.sub.3/C.sub.2 carbon molar ratio greater than or equal to 4.0.

This invention relates to a catalyst system comprising (a) at least one layer of a first catalyst comprising a dehydrogenation active metal on a solid support; (b) at least one layer of a second catalyst comprising a metal oxide; and (c) at least one layer of a third catalyst comprising a transition metal on an inorganic support; wherein the at least one layer of a second catalyst is sandwiched between the at least one layer of a first catalyst and the at least one layer of a third catalyst; and a process comprising contacting a hydrocarbon feed with the catalyst system.

This invention relates to a catalyst system comprising (a) at least one layer of a first catalyst comprising a dehydrogenation active metal on a solid support; (b) at least one layer of a second catalyst comprising a metal oxide; and (c) at least one layer of a third catalyst comprising a transition metal on an inorganic support; wherein the at least one layer of a second catalyst is sandwiched between the at least one layer of a first catalyst and the at least one layer of a third catalyst; and a process comprising contacting a hydrocarbon feed with the catalyst system.

The present invention relates to a hydrocarbon conversion process comprising contacting a hydrocarbon feed stream with a hydrocarbon conversion catalyst, wherein the hydrocarbon conversion catalyst comprises a first composition comprising a dehydrogenation active metal on a solid support; and a second composition comprising a transition metal and a doping agent on an inorganic support, wherein the doping agent is selected from zinc, gallium, indium, lanthanum, and mixtures thereof.

The present invention relates to a hydrocarbon conversion process comprising contacting a hydrocarbon feed stream with a hydrocarbon conversion catalyst, wherein the hydrocarbon conversion catalyst comprises a first composition comprising a dehydrogenation active metal on a solid support; and a second composition comprising a transition metal and a doping agent on an inorganic support, wherein the doping agent is selected from zinc, gallium, indium, lanthanum, and mixtures thereof.

A catalyst including at least one group 10 metal impregnated in a mixed metal oxide is provided. The mixed metal oxide is selected from the group consisting of the oxides of In, Cu. Zn, Zr, Al, and combinations thereof. The catalyst is effective in the conversion of CO.sub.2 to value added products like methanol (CH.sub.3OH) and carbon monoxide (CO). A convenient process for preparation of the catalyst is also provided.

A catalyst including at least one group 10 metal impregnated in a mixed metal oxide is provided. The mixed metal oxide is selected from the group consisting of the oxides of In, Cu. Zn, Zr, Al, and combinations thereof. The catalyst is effective in the conversion of CO.sub.2 to value added products like methanol (CH.sub.3OH) and carbon monoxide (CO). A convenient process for preparation of the catalyst is also provided.

The invention relates to a method for preparing a material made of silicon and/or germanium nanowires, comprising the steps of: i) placing a source of silicon and/or a source of germanium in contact with a catalyst comprising a binary metal sulfide or a multinary metal sulfide, said metal(s) being selected from among Sn, In, Bi, Sb, Ga, Ti, Cu, and Zn, by means of which silicon and/or germanium nanowires are obtained, ii) optionally recovering the silicon and/or germanium nanowires obtained in step (i); the catalyst and, optionally, the source of silicon and/or the source of germanium being heated before, during and/or after being placed in contact under temperature and pressure conditions that allow the growth of the silicon and/or germanium nanowires.