Propane dehydrogenation sulfur management

Patent metadata

Field	Value
Publication number	US-2016289144-A1
Application number	US-201415037242-A
Country	US
Kind code	A1
Filing date	Dec 3, 2014
Priority date	Dec 20, 2013
Publication date	Oct 6, 2016
Grant date	—

Abstract

Manage sulfur present as sulfur or a sulfur compound in a hydrocarbon feedstream while effecting dehydrogenation of hydrocarbon(s) (e.g. propane) contained in the hydrocarbon feedstream to its/their corresponding olefin (e.g. propylene where the hydrocarbon is propane) without subjecting the feedstream to desulfurization before it contacts a fluidizable dehydrogenation catalyst that is both a desulfurant and a dehydrogenation catalyst and comprises gallium and platinum on an alumina or alumina-silica catalyst support with optional alkaline or alkaline earth metal such as potassium. Contact with such a catalyst yields a desulfurized crude olefin product that corresponds to the hydrocarbon and has a reduced amount of sulfur or sulfur compounds relative to the sulfur or sulfur compounds present in the hydrocarbon feedstream prior to contact with the catalyst.

First claim

1 . A method for reducing sulfur present as sulfur or a sulfur compound in a hydrocarbon feedstream while effecting dehydrogenation of the hydrocarbon contained in the hydrocarbon feedstream comprising placing the hydrocarbon feedstream in contact with a fluidizable catalyst at a catalyst to hydrocarbon feed ratio in the range of from 1 to 100 wherein the fluidizable catalyst is both a desulfurant and a dehydrogenation catalyst and comprises gallium in an amount within a range of from greater than 0 percent by weight to 5 percent by weight, and platinum in an amount within a range of from greater than 1 to 300 parts by weight per million parts by weight of the catalyst on an alumina or alumina-silica catalyst support optionally with 0.01 to 5 percent by of alkaline and/or earth-alkaline such as potassium, under conditions sufficient to effect both removal from the hydrocarbon feedstream of at least a portion of the sulfur or sulfur compound contained therein, the amount of sulfur or sulfur compound in the feedstream prior to contact with the catalyst being within a range of from at least 1 part by weight per million parts by weight of feedstream to less than 1000 parts by weight per million parts by weight of feedstream, and dehydrogenation of the hydrocarbon to yield a desulfurized crude olefin product that corresponds to the hydrocarbon; the desulfurized crude olefin product containing a reduced amount of sulfur or sulfur compounds relative to the sulfur or sulfur compounds present in the hydrocarbon feedstream prior to contact with the catalyst.

2 . The method of claim 1 , further comprising sequential steps of a) effecting separation of the desulfurized crude olefin product from the catalyst onto which at least a portion of the sulfur is absorbed; and b) subjecting at least a portion of such catalyst to regeneration with air as a regeneration gas in a combustion portion of the process.

3 . The method of claim 2 , wherein the combustion portion of the process occurs in an upflow reactor with a net upward flow of catalyst and gases or counterflow configuration with a net upward flow of air and fuel and downward flow of catalyst followed by a subsequent greater than 2 minute oxygen treatment generally with air.

4 . The method of claim 1 , wherein regeneration occurs at a temperature within a range of from 550° centigrade to 800° centigrade.

5 . The method of claim 4 , wherein the reactor operates at a weight hourly space velocity (WHSV) within a range of from 0.1 hr −1 to 1000 hr −1 .

6 . The method of claim 4 , wherein the combustion portion of the regenerator operates with a weight hourly space velocity within a range of from 0.5 hr −1 to 1000 hr −1 .

7 . The method of claim 1 , wherein the catalyst support is alumina-silica with an alumina content within a range of from 90 to 99.5 percent by weight and a silica content within a range of from 0.5 to 10 percent by weight, both percentages being based upon total catalyst support weight and, when added together, total 100 percent by weight.

8 . The method of claim 7 , wherein the alumina content is within a range of from 97 to 99.5 percent by weight and the silica content is within a range of from 0.5 to 3 percent by weight, both percentages being based upon total catalyst support weight and, when added together, total 100 percent by weight.

9 . The method of claim 1 , wherein the reduced amount of sulfur or sulfur compound is less than 50 percent of the amount of sulfur or sulfur compound in the feedstream prior to contact with the catalyst.

10 . The method of any of claim 1 , wherein the amount of sulfur or sulfur compound in the feedstream prior to contact with the catalyst causes a drop in catalyst dehydrogenation activity over an average catalyst residence time within a range of from 0.1 minute to 10 minutes of less than 30 percent versus an equivalent case with no sulfur in the feed as measured by fixed bed experimental results.

Assignees

• Dow Global Technologies Llc

Inventors

• Pretz Matthew T
• Luo Lin
• Stears Brien A
• Stewart Mark W

Classifications

• C07C2521/12

  Silica and alumina · CPC title

• C07C2523/04

  Alkali metals · CPC title

• C10G9/00

  Thermal non-catalytic cracking, in the absence of hydrogen, of hydrocarbon oils · CPC title

• C10G35/09

  Bimetallic catalysts in which at least one of the metals is a platinum group metal · CPC title

• C07C5/3337 Primary

  of the platinum group · CPC title