Catalysts containing a support and a metal oxide, and reactors and methods of using the catalysts in a carbonylation reaction, such as alcohol carbonylation and ester carbonylation, are described herein. The support is typically chemically inert and has a high surface area. The metal oxide typically contains a transition metal or a mixture of metals, such as rhenium, aluminum, tungsten, molybdenum, or a combination thereof. Typically, the metal oxide is mainly atomically dispersed on the surface of the support, as indicated by STEM. For example, at least 10% of the metal oxide is atomically dispersed on the surface of the support. The method includes (i) exposing a mixture of one or more alcohols or one or more esters and carbon monoxide to the catalyst. Typically, the one or more alcohols or one or more esters and carbon monoxide are in a gas phase.

Disclosed are a catalyst and a preparation method therefor, the catalyst being able to maintain a high production yield of C8 aromatic hydrocarbons in the process of converting a feedstock containing alkyl aromatics to C8 aromatic hydrocarbons such as mixed xylene through disproportionation/transalkylation/dealkylation while reducing a content of ethylbenzene in the products.

Disclosed are a bifunctional catalyst and a preparation method therefor, the bifunctional catalyst being suitable to produce high-value aromatic hydrocarbons by subjecting alkylaromatic hydrocarbons to a disproportionation/transalkylation/dealkylation reaction while suppressing aromatic loss or subjecting C8 aromatic hydrocarbons to an isomerization reaction while suppressing xylene loss.

A process includes reacting a feed stream containing ethanol and optionally acetaldehyde in a dehydration reactor in the presence of a dehydration catalyst system having a Group 4 or Group 5 metal oxide and a support. The process includes obtaining a product stream containing butadiene from the dehydration reactor. Another process includes reacting a feed stream containing ethanol and optionally acetaldehyde in a dehydration reactor in the presence of a dehydration catalyst system containing a tungsten oxide supported on a zeolite or a tantalum oxide supported on a zeolite. The process includes obtaining a product stream containing butadiene from the dehydration reactor.

A process for isomerizing an aromatic cut containing at least one aromatic compound containing eight carbon atoms per molecule is described, comprising bringing said cut into contact with at least one catalyst comprising at least one metal from group VIII of the periodic classification of the elements, at least one zeolitic support comprising a zeolite selected from zeolites with structure type EUO and MOR, used alone or as a mixture, and at least one matrix, such that the specific surface area of the matrix in the zeolitic support of said catalyst is in the range 5 to 200 m.sup.2/g.

The present invention relates to a stabilized rhenium-based heterogeneous catalyst, obtainable by a process comprising contacting a rhenium-based heterogeneous catalyst with a stabilizing agent at a temperature in a range from 0-100° C., the stabilizing agent comprising an aliphatic hydrocarbon compound and use thereof.

A method is provided comprising exposing a supported heterogeneous metathesis catalyst to an olefin compound for an activation time at an activation temperature; exposing the activated supported heterogeneous metathesis catalyst to a reactant capable of undergoing a metathesis reaction for a reaction time at a reaction temperature to produce metathesis products; and exposing the deactivated supported heterogeneous metathesis catalyst to a regenerating compound for a regeneration time at a regeneration temperature. The activity of the regenerated supported heterogeneous metathesis catalyst may be substantially the same or greater than the activity of the activated supported heterogeneous metathesis catalyst prior to deactivation. The activation temperature may be greater than the reaction temperature. The regenerating compound may be a second olefin compound or an inert gas.

Alkyl-demethylation of C2+-hydrocarbyl substituted aromatic hydrocarbons can be utilized to treat one or more of a heavy naphtha reformate stream, a hydrotreated SCN stream, a C8 aromatic hydrocarbon isomerization feed stream, a C9+ aromatic hydrocarbon transalkylation feed stream, and similar hydrocarbon streams to produce additional quantity of xylene products.

Alkyl-demethylation of C2+-hydrocarbyl substituted aromatic hydrocarbons can be utilized to treat one or more of a heavy naphtha reformate stream, a hydrotreated SCN stream, a C8 aromatic hydrocarbon isomerization feed stream, a C9+ aromatic hydrocarbon transalkylation feed stream, and similar hydrocarbon streams to produce additional quantity of xylene products.

Disclosed are a catalyst and a preparation method therefor, the catalyst being able to maintain a high production yield of C8 aromatic hydrocarbons in the process of converting a feedstock containing alkyl aromatics to C8 aromatic hydrocarbons such as mixed xylene through disproportionation/transalkylation/dealkylation while reducing a content of ethylbenzene in the products.