Method for converting methane to ethylene

Patent metadata

Field	Value
Publication number	US-2016237003-A1
Application number	US-201415028986-A
Country	US
Kind code	A1
Filing date	Oct 15, 2014
Priority date	Oct 16, 2013
Publication date	Aug 18, 2016
Grant date	—

Abstract

In an embodiment, a process for producing ethylene comprising: introducing a methane stream comprising methane, oxygen, and water to a methane coupling zone; reacting the methane, the oxygen, and the water in the methane coupling zone via a methane oxidative coupling reaction to produce a first product stream; introducing the first product stream to a pyrolysis zone; and pyrolyzing ethane in the first product stream in the pyrolysis zone to produce a second product stream comprising ethylene. A heat from the methane coupling reaction is used in the pyrolysis reaction.

First claim

I/We claim:

1 . A process for producing ethylene comprising:
introducing a methane stream comprising methane, oxygen, and water to a methane coupling zone; reacting the methane, the oxygen, and the water in the methane coupling zone via a methane oxidative coupling reaction to produce a first product stream; introducing the first product stream to a pyrolysis zone; and pyrolyzing ethane in the first product stream in the pyrolysis zone to produce a second product stream comprising ethylene; wherein a heat from the methane coupling reaction is used in the pyrolysis reaction.

2 . The process of claim 1 , wherein the second product stream comprises greater than or equal to 10 vol % ethylene based on the total volume of the second product stream.

3 . The process of claim 1 , wherein the methane oxidative coupling reaction is facilitated by a catalyst and wherein the catalyst comprises a metal oxide, wherein the metal comprises Li, Mg, Sr, La, Na, Mn, or a combination comprising one or more of the foregoing.

4 . The process of claim 3 , wherein the catalyst comprises Na—Mn—O/SiO 2 .

5 . The process of claim 1 , further comprising separating natural gas into the methane stream and an ethane stream prior to introducing the methane stream.

6 . The process of claim 5 , further comprising introducing the ethane stream to the pyrolysis zone.

7 . The process of claim 1 , wherein the oxygen stream comprises air.

8 . The process of claim 1 , further comprising separating a recycle ethane stream from the second product stream and introducing the recycle ethane stream to the pyrolysis zone.

9 . The process of claim 1 , wherein the second product stream comprises methane and the methane is directed to a power plant and used as a fuel source.

10 . The process of claim 1 , wherein all of the first product stream is introduced into the pyrolysis zone.

11 . The process of claim 1 , wherein the methane oxidative coupling reaction occurs in an oxidative conversion reactor and the pyrolyzing occurs in a pyrolysis reactor.

12 . A process for producing ethylene comprising:
introducing a methane stream comprising methane, oxygen, and water to a methane coupling zone; reacting the methane, the oxygen, and the water in the methane coupling zone via a methane oxidative coupling reaction to produce a first product stream; introducing the first product stream to a pyrolysis zone; and pyrolyzing ethane in the first product stream in the pyrolysis zone to produce a second product stream comprising ethylene; wherein a heat from the methane coupling reaction is used in the pyrolysis reaction; wherein the methane oxidative coupling reaction occurs in an oxidative conversion zone in a reactor and the pyrolyzing occurs in a pyrolysis zone in the same reactor.

13 . The process of claim 1 , further comprising introducing a hydrocarbon stream to the pyrolysis zone.

14 . The process of claim 13 , wherein the hydrocarbon stream comprises naphtha.

15 . The process of claim 13 , wherein the hydrocarbon stream comprises ethane.

16 . The process of claim 1 , wherein the coupling reaction occurs at a temperature of 750 to 900° C.

17 . The process of claim 16 , wherein the reaction occurs at a temperature of 790 to 810° C.

18 . The process of claim 1 , further comprising separating a purified ethylene from the second product stream.

19 . A process for producing ethylene comprising:
separating natural gas into a methane stream and an ethane stream; introducing the methane stream comprising methane, oxygen, and water to a methane coupling zone; reacting the methane, the oxygen, and the water in the methane coupling zone via a methane oxidative coupling reaction to produce a first product stream; introducing the first product stream and the ethane stream to a pyrolysis zone; pyrolyzing ethane in the first product stream in the pyrolysis zone to produce a second product stream comprising greater than or equal to 10 vol % ethylene based on the total volume of the second product stream; and separating a recycle ethane stream from the second product stream and introducing the recycle ethane stream to the pyrolysis zone; wherein a heat from the methane coupling reaction is used in the pyrolysis reaction.

20 . The process of claim 19 , wherein the methane oxidative coupling reaction occurs in an oxidative conversion zone in a reactor and the pyrolyzing occurs in a pyrolysis zone in the same reactor.

Assignees

• Saudi Basic Ind Corp

Inventors

• Mammadov Aghaddin Kh
• Huckman Michael E
• Zhang Xiankuan

Classifications

• C07C2/84 Primary

  catalytic · CPC title

• C07C2521/08

  Silica · CPC title

• C07C2523/34

  Manganese · CPC title

• C07C5/48

  with oxygen as an acceptor · CPC title

• C10G2400/20

  C2-C4 olefins · CPC title