Dual catalyst system for propylene production

Patent metadata

Field	Value
Publication number	US-10052618-B2
Application number	US-201715398196-A
Country	US
Kind code	B2
Filing date	Jan 4, 2017
Priority date	Jul 2, 2015
Publication date	Aug 21, 2018
Grant date	Aug 21, 2018

Abstract

Embodiments of processes for producing propylene utilize a dual catalyst system comprising a mesoporous silica catalyst impregnated with metal oxide and a mordenite framework inverted (MFI) structured silica catalyst downstream of the mesoporous silica catalyst, where the mesoporous silica catalyst includes a pore size distribution of at least 2.5 nm to 40 nm and a total pore volume of at least 0.600 cm3/g, and the MFI structured silica catalyst has a total acidity of 0.001 mmol/g to 0.1 mmol/g. The propylene is produced from the butene stream via metathesis by contacting the mesoporous silica catalyst and subsequent cracking by contacting the MFI structured silica catalyst.

First claim

What is claimed is:

1. A dual catalyst system for producing propylene from butene, the dual catalyst system comprising a metathesis catalyst zone and a cracking catalyst zone downstream of the metathesis catalyst zone where:
the metathesis catalyst zone comprises mesoporous silica catalyst impregnated with metal oxide, where the mesoporous silica catalyst includes a pore size distribution of at least 2.5 nm to 40 nm and a total pore volume of at least 0.600 cm 3 /g; and
the cracking catalyst zone comprises a mordenite framework inverted (MFI) structured silica catalyst, where the MFI structured silica catalyst includes a pore size distribution of at least 1.5 nm to 3 nm, and a total acidity of 0.001 mmol/g to 0.1 mmol/g.

2. The dual catalyst system of claim 1 where the metathesis catalyst zone and the cracking catalyst zone are disposed in one reactor.

3. The dual catalyst system of claim 1 where the metathesis catalyst zone is disposed in a first reactor and the cracking catalyst zone is disposed in a second reactor downstream of the first reactor.

4. The dual catalyst system of claim 3 further comprising a conduit between the first reactor and the second reactor.

5. The dual catalyst system of claim 1 where the metal oxide of the mesoporous silica catalyst comprises one or more oxides of molybdenum, rhenium, tungsten, or combinations thereof.

6. The dual catalyst system of claim 1 where the mesoporous silica catalyst has a molar ratio for silica/metal oxide of 10 to 50.

7. The dual catalyst system of claim 1 where the metal oxide of the mesoporous silica catalyst is tungsten oxide (WO 3 ).

8. The dual catalyst system of claim 1 where the MFI structured silica catalyst is alumina free.

9. The dual catalyst system of claim 1 where the MFI structured silica catalyst comprises alumina.

10. The dual catalyst system of claim 9 where the MFI structured silica catalyst has a molar ratio of silica to alumina of 200 to 3000.

11. The dual catalyst system of claim 1 where the MFI structured silica catalyst is free of acidity modifiers selected from the group consisting of rare earth modifiers, phosphorus modifiers, potassium modifiers, and combinations thereof.

Assignees

• Saudi Arabian Oil Co
• Univ King Fahd Pet & Minerals

Inventors

• Al-Khattaf Sulaiman Saleh
• Palani Arudra
• Bhuiyan Tazul Islam
• Shaikh Sohel
• Akhtar Mohammad Naseem
• Aitani Abdullah M
• Al-Yami Mohammed A

Classifications

• B01J2229/183

  in framework positions · CPC title

• C07C6/06

  at a cyclic carbon-to-carbon double bond · CPC title

• B01J29/0358

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

• B01J37/0018

  Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat) · CPC title

• B01J29/40

  of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively · CPC title