A system for oxidative conversion of a mixed hydrocarbon feed stream to a product stream containing at least one olefin is provided. The system includes a plurality of reactors each capable of oxidatively dehydrogenating at least a portion of a hydrocarbon in the mixed hydrocarbon feed, and each reactor able to operate at different set of reaction conditions from other reactors in the plurality of reactors. All of the reactors use the same oxygen transfer agent to produce at least one olefin. In some embodiments, at least one reactor is optimized to oxidatively couple methane to produce ethylene, while other reactors are optimized to oxidatively dehydrogenate ethane to ethylene or to oxidatively dehydrogenate propane to ethylene and/or propylene. All of the reactors feed into a single regeneration unit for the oxygen transfer agent. A method of oxidatively converting the mixed hydrocarbon feed to an olefin is also provided.

The oxidative coupling of methane (OCM) and the oxidative dehydrogenation (ODH) of ethane and higher hydrocarbons is described using SO.sub.3 and sulfate, sulfite, bisulfite and metabifulfite salts as oxygen transfer agents in the presence of one or more elements selected from Groups 3 to 14 of the periodic table, optionally further in the presence of alkali or alkaline salts and/or sulfur-containing compounds.

Enhanced oxygen transfer agent systems and methods of use thereof are provided. According to one aspect, a method for producing olefins from a hydrocarbon feed includes the step of contacting a hydrocarbon feed comprised of one or more alkanes with an oxygen transfer agent at a temperature of 350° C. to 1000° C. The oxygen transfer agent includes an oxygen-donating chalcogen agent including at least one of S, Se, or Te and a reducible metal oxide. The chalcogen has an oxidation state greater than +2. A method for producing one or more olefins by partial combustion of a hydrocarbon feed is provided. The method includes partially combusting a hydrocarbon feed comprised of one or more alkanes by contacting the hydrocarbon feed with an oxygen transfer agent comprising CaSO.sub.4 at a temperature of 350° C. to 1000° C. to produce one or more olefins comprising ethylene and coproducing water.

Improvements in the commercial viability of oxygen transfer agents (OTAs) and/or catalysts associated with the OCM and the ODH of hydrocarbons to olefins through enhancement of one or more of the selectivity, yield, rate and lifetime of the OTA and/or catalyst is described by one or more of (i) exposing the OTA or the catalyst to a sulfur-containing compound at a site or at a time that is different from where and when the saturated hydrocarbon is converted by the OTA or the catalyst to an unsaturated hydrocarbon; (ii) increasing the particle density of the OTA or the catalyst by treating the OTA or the catalyst with a reducing agent at a site different from where the saturated hydrocarbon is converted by the OTA or by the catalyst to an unsaturated hydrocarbon; and (iii) removing non-selective redox oxygen (NSRO) present on the OTA by subjecting the OTA to a gas that is substantially free of any molecular oxygen.

A method of producing at least one compound comprising an alkenyl group from at least one compound comprising an alkyl group having two or more carbon atoms, the method comprising: (i) Providing a mixture comprising carbon dioxide and at least one compound comprising an alkyl group having two or more carbon atoms; and (ii) Contacting said mixture with a catalyst comprising one or both of palladium and platinum and one or more lanthanide, thereby converting at least a portion of the at least one compound comprising an alkyl group having two or more carbon atoms into a compound comprising an alkenyl group, the total of the weight of the palladium and/or platinum being more than 0.1 wt % of the catalyst.

Aspects of the invention relate to enhanced oxygen transfer agent systems and methods of use thereof. According to one aspect, a method for producing olefins from a hydrocarbon feed includes the step of contacting a hydrocarbon feed comprised of one or more alkanes with an oxygen transfer agent at a temperature of 350° C. to 1000° C. The oxygen transfer agent comprising an oxygen-donating chalcogen agent comprised of at least one of S, Se, or Te and a reducible metal oxide. The chalcogen having an oxidation state greater than +2. According to another aspect, a method for producing one or more olefins by partial combustion of a hydrocarbon feed includes partially combusting a hydrocarbon feed comprised of one or more alkanes by contacting the hydrocarbon feed with an oxygen transfer agent comprising CaS0.sub.4 at a temperature of 350° C. to 1000° C. to produce one or more olefins comprising ethylene and coproducing water.

Provided herein is a unique process that prepares a saturated hydrocarbon mixture with well-controlled structural characteristics that address the performance requirements driven by the stricter environmental and fuel economy regulations for automotive engine oils. The process allows for the branching characteristics of the hydrocarbon molecules to be controlled so as to consistently provide a composition that has a surprising CCS viscosity at −35° C. (ASTM D5329) and Noack volatility (ASTM D5800) relationship. The process comprises providing a specific olefinic feedstock, oligomerizing in the presence of a BF.sub.3 catalyst, and hydroisomerizing in the presence of a noble-metal impregnated, 10-member ring zeolite catalyst.

Provided herein is a unique process that prepares a saturated hydrocarbon mixture with well-controlled structural characteristics that address the performance requirements driven by the stricter environmental and fuel economy regulations for automotive engine oils. The process allows for the branching characteristics of the hydrocarbon molecules to be controlled so as to consistently provide a composition that has a surprising CCS viscosity at 35 C. (ASTM D5329) and Noack volatility (ASTM D5800) relationship. The process comprises providing a specific olefinic feedstock, oligomerizing in the presence of a BF.sub.3 catalyst, and hydroisomerizing in the presence of a noble-metal impregnated, 10-member ring zeolite catalyst.

The present invention relates to a chrome compound composed of non-coordinating anions and a trivalent chrome cation, a reactant of the chrome compound and a bidentate ligand, an ethylene oligomerization reaction catalyst system using the chrome compound and the reactant, and a method for preparing an ethylene oligomer using the catalyst system. Through the above conformation, the present invention can selectively produce 1-hexene and 1-octene with high activity while omitting the use of methylaluminoxane (MAO), and can provide an ethylene oligomerization process more suitable for mass production.

Heterogeneous catalysts with optional dopants are provided. The catalysts are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane to C.sub.2+ hydrocarbons. Related methods for use and manufacture of the same are also disclosed.