To provide a platinum-loaded alumina catalyst with an improved catalyst life.

A platinum-loaded alumina catalyst includes an alumina carrier, and platinum loaded on the alumina carrier, wherein the alumina carrier includes a γ-alumina carrier having a surface area of 200 m.sup.2/g or more, a pore volume of 0.50 m.sup.2/g or more, an average pore diameter in a range of 60 to 150 Å, with pores having a pore diameter in a range of ±30 Å from the average pore diameter occupying 60% or more of a total pore volume, platinum particles are loaded on γ-alumina carrier in a range of 0.1 to 1.5% by weight calculated as elemental platinum (Pt), and 70% or more of the platinum particles have a size of 8 to 15 Å by direct observation using a transmission electron microscope.

Embodiments of a system and method are disclosed for obtaining high-energy fuels. In some embodiments, the system and method produces one or more fused cyclic compounds that can include one or more bridging points. The fused cyclic compounds are suitable for use as a high-energy fuels, and may be derived from biomass.

Embodiments of a system and method are disclosed for obtaining high-energy fuels. In some embodiments, the system and method produces one or more fused cyclic compounds that can include one or more bridging points. The fused cyclic compounds are suitable for use as a high-energy fuels, and may be derived from biomass.

A method for processing a chemical stream includes contacting a feed stream with a catalyst in a reactor portion of a reactor system that includes a reactor portion and a catalyst processing portion. The catalyst includes platinum, gallium, or both and contacting the feed stream with the catalyst causes a reaction which forms an effluent stream. The method includes separating the effluent stream from the catalyst, passing the catalyst to the catalyst processing portion, and processing the catalyst in the catalyst processing portion. Processing the catalyst includes passing the catalyst to a combustor, combusting a supplemental fuel in the combustor to heat the catalyst, treating the heated catalyst with an oxygen-containing gas to produce a reactivated catalyst, and passing the reactivated catalyst from the catalyst processing portion to the reactor portion. The supplemental fuel may include a molar ratio of hydrogen to other combustible fuels of at least 1:1.

The present disclosure relates to chromium-on-alumina dehydrogenation catalyst materials, to methods for making such catalysts, and to methods for dehydrogenating hydrocarbons using such catalysts. In one aspect, the disclosure provides a method for preparing a dehydrogenation catalyst material, the method comprising impregnating a chromium-on-alumina material with ascorbic acid, one or more of sodium, lithium and potassium (e.g., sodium), and chromium; and calcining the impregnated material to provide the dehydrogenation catalyst material comprising chromium in the range of 2.5 wt. % to about 35 wt. % and having no more than 100 ppm chromium(VI).

The present invention relates to catalysts, catalyst systems, and processes for the production of valuable light olefins, such as C.sub.2-C.sub.4 olefins (ethylene, propylene, and/or butenes) from paraffinic hydrocarbons, such as propane, through dehydrogenation and metathesis. Some particular aspects relate to the discovery of non-precious metal catalysts and catalyst systems utilizing such catalysts, for example in the case of being in an admixture with a metathesis catalyst, which advantageously exhibit high performance in terms of activity, selectivity, and stability. Other advantages can include a reduced production of byproducts (e.g., methane and ethane) that result from undesired side reactions, in addition to benefits that may be attained through the addition of a sulfur-bearing compound (e.g., H.sub.2S).

A process for endothermic dehydrogenation including contacting a catalyst material in a moving bed reactor having at least one reaction zone, the moving bed reactor comprising a heat exchanger containing a heating medium, wherein the catalyst material and the heating medium do not contact one another, and wherein at least 50% of the delta enthalpy of the at least one reaction zone is provided by the heat exchanger; and contacting a feedstock comprising hydrocarbons with the catalyst material in the at least one reaction zone of the moving bed reactor under reaction conditions to convert at least a portion of the hydrocarbons to a first effluent comprising a product comprising alkenes, alkynes, cyclic hydrocarbons, and/or aromatics.

A process for endothermic dehydrogenation including contacting a catalyst material in a moving bed reactor having at least one reaction zone, the moving bed reactor comprising a heat exchanger containing a heating medium, wherein the catalyst material and the heating medium do not contact one another, and wherein at least 50% of the delta enthalpy of the at least one reaction zone is provided by the heat exchanger; and contacting a feedstock comprising hydrocarbons with the catalyst material in the at least one reaction zone of the moving bed reactor under reaction conditions to convert at least a portion of the hydrocarbons to a first effluent comprising a product comprising alkenes, alkynes, cyclic hydrocarbons, and/or aromatics.

A process for endothermic dehydrogenation including contacting a catalyst material in a moving bed reactor having at least one reaction zone, the moving bed reactor comprising a heat exchanger containing a heating medium, wherein the catalyst material and the heating medium do not contact one another, and wherein at least 50% of the delta enthalpy of the at least one reaction zone is provided by the heat exchanger; and contacting a feedstock comprising hydrocarbons with the catalyst material in the at least one reaction zone of the moving bed reactor under reaction conditions to convert at least a portion of the hydrocarbons to a first effluent comprising a product comprising alkenes, alkynes, cyclic hydrocarbons, and/or aromatics.

A method for processing a chemical stream includes contacting a feed stream with a catalyst in a reactor portion of a reactor system that includes a reactor portion and a catalyst processing portion. The catalyst includes platinum, gallium, or both and contacting the feed stream with the catalyst causes a reaction which forms an effluent stream. The method includes separating the effluent stream from the catalyst, passing the catalyst to the catalyst processing portion, and processing the catalyst in the catalyst processing portion. Processing the catalyst includes passing the catalyst to a combustor, combusting a supplemental fuel in the combustor to heat the catalyst, treating the heated catalyst with an oxygen-containing gas to produce a reactivated catalyst, and passing the reactivated catalyst from the catalyst processing portion to the reactor portion. The supplemental fuel may include a molar ratio of hydrogen to other combustible fuels of at least 1:1.