KR900012868A - Dehydrogenation of Light Alkanes - Google Patents

Abstract

No content

Description

Dehydrogenation of Light Alkanes

Since this is an open matter, no full text was included.

Claims (16)

(a) a feed stream comprising at least one alkan having from 2 to 5 carbon atoms per molecule in a reactor under dehydrogenation conditions, at least partially converting at least one alkan to at least one alkene, and At least one aluminate spinel selected from the group consisting of Group IIA metal aluminates and IIB metal aluminates, at least one metal selected from the group consisting of nickel, ruthenium, rhodium palladium, osmium, iridium and platinum, and III Contacting with a catalyst composition consisting of at least one compound of a metal selected from the group consisting of geranium, tin and lead, (b) substantially reducing the hydrogen oxide from the reactor, the feed stream comprising the catalyst composition Stops flowing through the reactor and stops steam, at least one inert Passing a purge gas stream selected from the group consisting of a mixture of a sieve and steam and at least one inert gas into the reactor, (c) thereafter substantially burning off the carbonaceous precipitate on the catalyst composition and obtaining a regeneration catalyst composition. In said reactor under regeneration conditions, contacting said catalyst composition with a gas stream comprising vapor and free oxygen; (d) removing said reactor comprising said regeneration catalyst composition to substantially remove free oxygen from said reactor. Stopping the flow of the gas stream comprising free oxygen therethrough and passing the purge gas through the reactor as described in step (b). (e) contacting the regeneration catalyst composition with a reducing gas stream consisting of free hydrogen and steam in the reactor under conditions such that a reactivated catalyst composition is obtained, wherein the molar ratio of free hydrogen in the vapor stream is about A trick of 2: 1-20: 1, (f) stopping the flow of free hydrogen through the reactor under dehydrogenation conditions such that at least partially converting the at least one alkan to at least one alkene, and Contacting said feed stream with steam and the regeneration catalyst composition obtained in step (e). The process of claim 1 wherein the reducing gas stream used in step (e) consists essentially of free hydrogen and steam. The method of claim 1 wherein said catalyst composition consists of zinc aluminate, platinum and tin oxide. 4. The method of claim 3 wherein the catalyst composition comprises calcium aluminate. The method of claim 1, wherein the catalyst composition consists of about 0.05-5% by weight of pt and about 0.1-5% by weight of Sn present as tin oxide. The process of claim 1, wherein the temperature range at the dehydrogenation conditions of steps (a) and (f) is about 500-about 650 ° C., and the molar ratio range of vapor: alkanes is about 0.5-about. 30: 1. The process according to any of claims 1 to 4, wherein essentially no hydrogen gas and oxygen gas are added to the reactor in steps (a) and (f). The process according to any one of claims 1 to 4, wherein in step (b) steam is used as the purge gas flow. The process of claim 1 wherein the temperature range at said regeneration conditions of (c) is from about 450 to about 750 ° C. and the molar ratio of vapor to free oxygen is in the range of about 40: 1 to about 200: 1. Way. The process according to any one of claims 1 to 4, wherein in step (d) steam is used as the purge gas flow. The process of claim 1, wherein the reducing step (e) is carried out at a temperature of about 450-about 650 ° C. for about 1 to about 60 minutes. 5. The method according to claim 1, wherein said at least one alkan is propane, n-butane or isobuta. The process according to any one of claims 1 to 4, wherein the at least one alkene obtained in steps (a) and (f) is propylene, butene-1, butene-2 and isobutene. The method of any one of claims 1 to 4, wherein steps (b)-(f) are repeated at least once. The method of any one of claims 1 to 4, wherein at least one alkene obtained in steps (a) and (f) is recovered. The process according to any one of claims 1 to 4, wherein the catalyst composition consists essentially of (I), (II) and (III). ※ Note: The disclosure is based on the initial application.