Catalytic hydrocarbon dehydrogenation

Patent metadata

Field	Value
Publication number	US-2021069677-A1
Application number	US-201916566778-A
Country	US
Kind code	A1
Filing date	Sep 10, 2019
Priority date	Sep 10, 2019
Publication date	Mar 11, 2021
Grant date	—

Abstract

A catalyst for dehydrogenation of hydrocarbons includes a support including zirconium oxide and alumina. A concentration of the zirconium oxide in the catalyst is in a range of from 1 weight percent (wt. %) to 20 wt. %. The catalyst includes from 0.01 wt. % to 2 wt. % of an alkali metal or alkaline earth metal. The catalyst includes from 1 wt. % to 2 wt. % of tin. The catalyst includes from 0.1 wt. % to 2 wt. % of a platinum group metal. The alkali metal or alkaline earth metal, tin, and platinum group metal are disposed on the support.

First claim

What is claimed is:

1 . A catalyst for dehydrogenation of hydrocarbons, the catalyst comprising:
a support comprising zirconium oxide and alumina, wherein a concentration of the zirconium oxide in the catalyst is in a range of from 1 weight percent (wt. %) to 20 wt. %; from 0.01 wt. % to 2 wt. % of an alkali metal or alkaline earth metal, the alkali metal or alkaline earth metal disposed on the support; from 1 wt. % to 2 wt. % of tin, the tin disposed on the support; and from 0.1 wt. % to 2 wt. % of a platinum group metal, the platinum group metal disposed on the support.

2 . The catalyst of claim 1 , wherein the alkali metal or alkaline earth metal is selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, and barium.

3 . The catalyst of claim 2 , wherein the alkali metal is potassium or cesium.

4 . The catalyst of claim 2 , wherein the alumina comprises gamma-alumina or theta-alumina.

5 . The catalyst of claim 2 , wherein the platinum group metal is selected from the group consisting of platinum, ruthenium, iridium, rhodium, and palladium.

6 . The catalyst of claim 2 , wherein the catalyst is configured to dehydrogenate hydrocarbons including 3 to 6 carbon atoms at an operating temperature in a range of from about 500 degrees Celsius (° C.) to about 800° C. and an operating pressure in a range of from about 0.01 bar to about 10 bar.

7 . The catalyst of claim 6 , wherein the catalyst is configured to dehydrogenate hydrocarbons including 3 to 6 carbon atoms in the presence of a diluent gas comprising hydrogen, steam, inert gas, or combinations thereof.

8 . The catalyst of claim 7 , wherein a concentration of hydrogen in the diluent gas is in a range of from 5 volume percent (vol. %) to 30 vol. %.

9 . A method of dehydrogenating hydrocarbons, the method comprising:
subjecting the hydrocarbons to be dehydrogenated to an operating temperature in a range of from about 500 degrees Celsius (° C.) to about 800° C. within a reactor; subjecting the hydrocarbons to be dehydrogenated to an operating pressure in a range of from about 0.01 bar to about 10 bar within the reactor; while subjecting the hydrocarbons to the operating temperature and operating pressure within the reactor,
introducing a diluent gas within the reactor, the diluent gas comprising hydrogen, steam, inert gas, or combinations thereof; and
using a catalyst disposed within the reactor to dehydrogenate the hydrocarbons in the presence of the diluent gas within the reactor, the catalyst comprising:
a support comprising zirconium oxide and alumina, wherein a concentration of the zirconium oxide in the catalyst is in a range of from 1 weight percent (wt. %) to 20 wt. %;
from 0.01 wt. % to 2 wt. % of an alkali metal or alkaline earth metal, the alkali metal or alkaline earth metal disposed on the support;
from 1 wt. % to 2 wt. % of tin, the tin disposed on the support; and
from 0.1 wt. % to 2 wt. % of a platinum group metal, the platinum group metal disposed on the support.

10 . The method of claim 9 , wherein the alkali metal or alkaline earth metal is selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, and barium.

11 . The method of claim 10 , wherein the alkali metal is potassium or cesium.

12 . The method of claim 10 , wherein the alumina comprises gamma-alumina or theta-alumina.

13 . The method of claim 10 , wherein a concentration of hydrogen in the diluent gas is in a range of from 5 volume percent (vol. %) to 30 vol. %.

14 . The method of claim 10 , further comprising, before using the catalyst to dehydrogenate the hydrocarbons, activating the catalyst, wherein activating the catalyst comprises:
reducing the catalyst to form catalyst grains with diameters in a range of from 200 micrometers to 500 micrometers; placing the catalyst grains within the reactor; flowing a stream comprising oxygen to the catalyst grains within the reactor; while flowing the stream comprising oxygen to the catalyst grains, increasing a temperature within the reactor to 450° C.; after the temperature within the reactor reaches 450° C., flowing a stream comprising an inert gas to the catalyst grains within the reactor; while flowing the stream comprising the inert gas to the catalyst grains, decreasing the temperature within the reactor to 400° C.; after the temperature within the reactor reaches 400° C., flowing a stream comprising hydrogen to the catalyst grains within the reactor; and adjusting the temperature within the reactor to the operating temperature.

15 . A method of preparing a catalyst for dehydrogenation of hydrocarbons, the method comprising:
mixing an alumina with an aqueous solution of a first additive to form a first slurry, the first additive comprising a salt or complex comprising zirconium; drying the first slurry to form a first solid; mixing the first solid with an aqueous solution of a second additive to form a second slurry, the second additive comprising a salt comprising an alkali metal or an alkaline earth metal; drying the second slurry in the presence of oxygen to form a second solid; mixing the second solid with an ethanolic solution of a third additive to form a third slurry, the third additive comprising a salt or complex comprising tin; drying the third slurry to form a third solid; mixing the third solid with an aqueous solution of a fourth additive to form a fourth slurry, the fourth additive comprising a salt or complex comprising a platinum group metal; and drying the fourth slurry to form the catalyst having a composition comprising:
from 1 weight percent (wt. %) to 20 wt. % of zirconia derived from the first additive;
from 0.01 wt. % to 2 wt. % of the alkali metal or alkaline earth metal derived from the second additive;
from 1 wt. % to 2 wt. % of the tin derived from the third additive;
from 0.1 wt. % to 2 wt. % of the platinum group metal derived from the fourth additive; and
a balance of the alumina.

16 . The method of claim 15 , wherein the first additive is selected from the group consisting of zirconium oxynitrate, zirconium oxychloride, zirconium acetate, and zirconium acetylacetonate.

17 . The method of claim 15 , wherein an anionic portion of the salt in the second additive is selected from the group consisting of nitrate ion, nitrite ion, sulfate ion, hydroxide ion, and halide ion.

18 . The method of claim 15 , wherein the third additive is selected from the group consisting of tin(II) chloride dihydrate, tin(IV) chloride hydrate, and tin(IV) bis(acetylacetonate).

19 . The method of claim 15 , wherein the fourth additive is selected from the group consisting of dihydrogen hexachloroplatinate hexahydrate, tetraammineplatinum dihydroxide, tetraammineplatinum dinitrate, and tetraammineplatinum dichloride.

20 . The method of claim 15 , wherein the alumina is gamma-alumina or theta-alumina.

21 . The method of claim 20 , further comprising forming the gamma-alumina, wherein forming the gamma-alumina comprises:
dispersing alumina in water; adding nitric acid to the dispersion of alumina in water to form a first particulate sol; mixing the first particulate sol under reflux to form a second particulate sol, wherein a liquid phase of the second particulate sol is optically clear; freeze-drying the second particulate sol to form a dried solid; heating the dried solid in the presence of oxygen to form the gamm

Assignees

• Saudi Arabian Oil Co

Inventors

• Al-Daous Mohammed Abdulmajeed
• Bahlouli Hussam A

Classifications

• B01J23/626 Primary

  with tin · CPC title

• B01J23/58

  with alkali- or alkaline earth metals · CPC title

• B01J21/04

  Alumina · CPC title

• C07C5/325

  of the platinum group · CPC title

• B01J21/066 Primary

  Zirconium or hafnium; Oxides or hydroxides thereof · CPC title