The present invention provides a pyrolysis tube for manufacturing olefin which tube can improve a yield of olefin in a pyrolysis reaction of a hydrocarbon raw material. The pyrolysis tube (1A) for manufacturing olefin includes a tubular base material (2) made of a heat resistant metal material and a dehydrogenating catalyst (4A) which is supported on an inner surface of the tubular base material (2).

An improved catalytic dehydrogenation process which process comprises contacting an alkane or alkyl aromatic feedstream with a dehydrogenation catalyst under catalytic conditions in an up-flow fluidized reactor, wherein the fluidized reactor comprises one or more reactors, which catalytic conditions include a temperature within a range of from 500 to 800° C., a weight hourly space velocity within a range of from 0.1 to 1000, a gas residence time within a range of from 0.1 to 10 seconds, and, subsequent to the fluidized reactor, effecting separation of entrained catalyst from reactor effluent by use of a cyclonic separation system, wherein the improvement comprises interposing a cooling means between an up-flow fluidized reactor and the cyclonic separation system to substantially halt thermal reactions, thereby effectively increasing overall molar selectivity to alkene product is provided.

Catalysts and catalytic methods are provided. The catalysts and methods are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane.

The present disclosure provides a modified catalyst, and preparation method and a method for producing aromatic hydrocarbons by aromatization of olefins using the modified catalyst. The modified catalyst comprises an acidic molecular sieve and an olefin aromatization active metal component, the total acid amount of the catalyst as measured by NH3-TPD method is not higher than 0.35mmo1/g, and ratio of the strong acid to weak acid is within a range of 0.8-1.2.

According to one or more embodiments disclosed herein, methods for operating dehydrogenation processes during non-normal operating conditions, such as at start-up, shut-down, system recycle, or unit trip, are described. The methods may include contacting a feed stream with a catalyst in a reactor portion of a reactor system to form a reactor effluent stream, separating at least a portion of the reactor effluent stream from the catalyst, passing the catalyst to a catalyst processing portion and processing the catalyst, wherein processing the catalyst comprises contacting the catalyst with oxygen, passing the catalyst from the processing portion to the reactor portion, wherein the catalyst exiting the processing portion comprises at least 0.001 wt. % oxygen, and contacting the catalyst with supplemental hydrogen, the contacting removing at least a portion of the oxygen from the catalyst by a combustion reaction.

A catalyst for preparing light olefin using direct conversion of syngas is a composite catalyst and formed by compounding component I and component II in a mechanical mixing mode. The active ingredient of component I is a metal oxide; and the component II is one or more than one of zeolite of CHA and AEI structures or metal modified CHA and/or AEI zeolite. A weight ratio of the active ingredients in the component I to the component II is 0.1-20. The reaction process has high product yield and selectivity, wherein the sum of the selectivity of the propylene and butylene reaches 40-75%; and the sum of the selectivity of light olefin comprising ethylene, propylene and butylene can reach 50-90%. Meanwhile, the selectivity of a methane side product is less than 15%.

An organic base modified composite catalyst for producing ethylene by hydrogenation of carbon monoxide is a composite catalyst and formed by compounding component I and component II in a mechanical mixing mode. The active ingredient of the component I is a metal oxide; the component II is an organic base modified zeolite of MOR topology; and a weight ratio of the active ingredients in the component I to the component II is 0.1-20, and preferably 0.3-8. The reaction process has an extremely high product yield and selectivity. The selectivity of C.sub.2-C.sub.3 olefins is as high as 78-87%; the selectivity of hydrocarbon products with more than 4 C atoms is less than 10%; the selectivity of a methane side product is extremely low (<9%); and meanwhile, the selectivity of the ethylene is 75-82%.

A process for dehydrogenating alkane or alkylaromatic compounds comprising contacting the given compound and a dehydrogenation catalyst in a fluidized bed. The dehydrogenation catalyst is prepared from an at least partially deactivated platinum/gallium catalyst on an alumina-based support that is reconstituted by impregnating it with a platinum salt solution, then calcining it at a temperature from 400° C. to 1000° C., under conditions such that it has a platinum content ranging from 1 to 500 ppm, based on weight of catalyst; a gallium content ranging from 0.2 to 2.0 wt %; and a platinum to gallium ratio ranging from 1:20,000 to 1:4. It also has a Pt retention that is equal to or greater than that of a fresh catalyst being used in a same or similar catalytic process.

According to one or more embodiments disclosed herein, methods for operating dehydrogenation processes during non-normal operating conditions, such as at start-up, shut-down, system recycle, or unit trip, are described. The methods may include contacting a feed stream with a catalyst in a reactor portion of a reactor system to form a reactor effluent stream, separating at least a portion of the reactor effluent stream from the catalyst, passing the catalyst to a catalyst processing portion and processing the catalyst, wherein processing the catalyst comprises contacting the catalyst with oxygen, passing the catalyst from the processing portion to the reactor portion, wherein the catalyst exiting the processing portion comprises at least 0.001 wt. % oxygen, and contacting the catalyst with supplemental hydrogen, the contacting removing at least a portion of the oxygen from the catalyst by a combustion reaction.

A process for preparing C.sub.2 to C.sub.3 hydrocarbons may include introducing a feed stream including hydrogen gas and a carbon-containing gas comprising carbon monoxide, carbon dioxide, and mixtures thereof into a reaction zone of a reactor, and converting the feed stream into a product stream comprising C.sub.2 to C.sub.3 hydrocarbons in the reaction zone in the presence of a hybrid catalyst. The hybrid catalyst may include a metal oxide catalyst component and a microporous catalyst component comprising 8-MR pore openings and may be derived from a natural mineral, the product stream comprises a combined C.sub.2 and C.sub.3 selectivity greater than 40 carbon mol%.