Process of preparing catalyst; platinum-tin on zinc aluminate-calcium aluminate-zeolite catalyst for selective light alkane dehydrogenation

Patent metadata

Field	Value
Publication number	US-11040338-B2
Application number	US-201716465297-A
Country	US
Kind code	B2
Filing date	Dec 6, 2017
Priority date	Dec 6, 2016
Publication date	Jun 22, 2021
Grant date	Jun 22, 2021

Abstract

Disclosed are supported platinum-tin (Pt—Sn) based catalysts and methods of their use in selective light alkane dehydrogenation to corresponding alkenes and preparation. The supported catalysts contain a support of blended zeolite, in particular SAPO-34, zinc aluminate compound, and calcium aluminate, impregnated with Pt and Sn metal and a promoter that includes an alkali metal or compound thereof, an alkaline earth metal or compound thereof, or any combination thereof.

First claim

The invention claimed is:

1. A supported platinum-tin (Pt—Sn) based catalyst comprising:
a support comprising:
a zeolite;
a zinc aluminate compound; and
a calcium aluminate compound;

catalytically active metals comprising:
Pt metal or a compound thereof; and
Sn metal or a compound thereof; and

a promoter comprising an alkali metal selected from the group consisting of sodium and lithium or compound thereof, an alkaline earth metal or compound thereof, or any combination thereof; wherein the alkaline earth metal is not calcium;
wherein the promoter further comprises a member selected from the group consisting of scandium, hafnium, mercury and lead;
wherein if the promoter comprises hafnium, the promoter also comprises from 0.01 to 10 wt. % of the Pt metal or a compound thereof, based on the total weight of the catalyst.

2. The supported platinum-tin (Pt—Sn) based catalyst of claim 1 , comprising from 25 to 95 wt. % of the zinc aluminate, based on the total weight of the support.

3. The supported platinum-tin (Pt—Sn) based catalyst of claim 1 , wherein the promoter comprises lithium (Li).

4. The supported platinum-tin (Pt—Sn) based catalyst of claim 3 , wherein the promoter comprises sodium (Na).

5. The supported platinum-tin (Pt—Sn) based catalyst of claim 1 , wherein the promoter comprises mercury.

6. A process for preparing the supported platinum-tin (Pt—Sn) based catalyst of claim 1 , the process comprising the steps of:
(a) dry blending a zeolite, zinc aluminate, and calcium aluminate to form a support mixture;
(b) adding an acid to the support mixture to form a support mixture paste;
(c) calcining the support mixture paste to form a blended support material;
(d) impregnating the blended support material with an aqueous promoter precursor solution comprising an alkali metal selected from the group consisting of sodium and lithium or a compound thereof, an alkaline earth metal, scandium, hafnium, mercury, lead or a compound thereof;
(e) calcining the impregnated blended support material to form a calcined promoter/support material;
(f) impregnating the calcined promoter/support material with Pt and Sn to form a Pt/Sn/impregnated promoter/support material;
(g) calcining the Pt/Sn/impregnated promoter/support material to form the Pt—Sn based catalyst.

7. A supported platinum-tin (Pt—Sn) based catalyst comprising:
a support comprising:
a zeolite;
a zinc aluminate compound; and
a calcium aluminate compound;

catalytically active metals comprising:
Pt metal or a compound thereof; and
Sn metal or a compound thereof; and

a promoter consisting of lithium (Li), rubidium (Rb), cesium (Cs) and beryllium (Be).

8. A supported platinum-tin (Pt—Sn) based catalyst comprising:
a support comprising a blend of:
a zeolite;
a zinc aluminate compound; and
a calcium aluminate compound;

catalytically active metals comprising:
Pt metal or a compound thereof; and
Sn metal or a compound thereof; and

a promoter comprising an alkali metal or compound thereof, an alkaline earth metal or compound thereof, or any combination thereof; wherein the alkaline earth metal is not calcium;
wherein the support comprises from 5 to 75 wt. % of the zeolite, based on the total weight of the support; and
wherein the zeolite comprises a member selected from the group consisting of one or more of SAPO-34, SAPO-11, SAPO-35, ZSM-5, MCM-41 and SBA-15; and
wherein the promoter further comprises at least one member selected from the group consisting of vanadium, rhenium, silver and gold.

9. The supported platinum-tin (Pt—Sn) based catalyst of claim 8 , wherein the promoter comprises sodium and rhenium.

10. The supported platinum-tin (Pt—Sn) based catalyst of claim 8 , wherein the promoter comprises barium and rhenium.

11. The supported platinum-tin (Pt—Sn) based catalyst of claim 1 , wherein the zeolite comprises ZSM-5 and MCM-41.

Assignees

• Sabic Global Technologies Bv

Inventors

• Nawaz Zeeshan

Classifications

• B01J29/076

  containing arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium · CPC title

• B01J23/02

  of the alkali- or alkaline earth metals or beryllium · CPC title

• B01J2229/42

  Addition of matrix or binder particles · CPC title

• B01J23/005

  Spinels · CPC title

• B01J37/0207

  Pretreatment of the support · CPC title