Oxidative coupling of methane

Patent metadata

Field	Value
Publication number	US-11117848-B2
Application number	US-201816500249-A
Country	US
Kind code	B2
Filing date	Apr 9, 2018
Priority date	Apr 10, 2017
Publication date	Sep 14, 2021
Grant date	Sep 14, 2021

Abstract

The present invention relates to a process for oxidative coupling of methane (OCM), comprising the steps of: (a) contacting, in a reactor, oxygen and methane with an OCM catalyst, resulting in a reactor effluent comprising ethylene, ethane, methane, carbon dioxide and water; (b) cooling the reactor effluent to obtain a liquid stream comprising water and a gas stream comprising ethylene, ethane, methane and carbon dioxide; (c) removing carbon dioxide from at least a part of the gas stream comprising ethylene, ethane, methane and carbon dioxide resulting in a gas stream comprising ethylene, ethane and methane; (d) passing at least a part of the gas stream comprising ethylene, ethane and methane as obtained in step (c) through a membrane, preferably a membrane comprising metal cations, more preferably a membrane comprising silver (I) ions (Ag+ ions) or copper (I) ions (Cu+ ions), to obtain a stream comprising ethane and a stream comprising ethylene.

First claim

That which is claimed is:

1. A process for oxidative coupling of methane (OCM), comprising the steps of:
(a) contacting, in a reactor, oxygen and methane with an OCM catalyst, resulting in a reactor effluent comprising ethylene, ethane, methane, carbon dioxide and water;
(b) cooling the reactor effluent to obtain a liquid stream comprising water and a gas stream comprising ethylene, ethane, methane and carbon dioxide;
(c) removing carbon dioxide from at least a part of the gas stream comprising ethylene, ethane, methane and carbon dioxide resulting in a gas stream comprising ethylene, ethane and methane;
(d) passing at least a part of the gas stream comprising ethylene, ethane and methane as obtained in step (c) through a membrane to obtain a stream comprising ethane and methane and a stream comprising ethylene and ethane;
(e) feeding the stream comprising ethane and methane as obtained in step (d) to a distillation column to obtain a stream comprising ethane and a stream comprising methane;
(f) optionally feeding at least a part of the stream comprising methane as obtained in step (e) to step (a);
(g) passing at least a part of the stream comprising ethylene and ethane as obtained in step (d) through a second membrane to obtain a stream comprising ethane and ethylene and a stream comprising ethylene; and
(h) optionally feeding at least a part of the stream comprising ethane and ethylene as obtained in step (g) to the membrane used in step (d), or optionally feeding at least a part of the stream comprising ethane and ethylene as obtained in step (g) to step (a).

2. The process according to claim 1 , wherein the membrane comprises metal cations.

3. The process according to claim 2 , wherein the membrane comprises silver(I) ions (Ag+ions) or copper(I) ions (Cu + ions).

4. A process for oxidative coupling of methane (OCM), comprising the steps of:
(a) contacting, in a reactor, oxygen and methane with an OCM catalyst, resulting in a reactor effluent comprising ethylene, ethane, methane, carbon dioxide and water;
(b) cooling the reactor effluent to obtain a liquid stream comprising water and a gas stream comprising ethylene, ethane, methane and carbon dioxide;
(c) removing carbon dioxide from at least a part of the gas stream comprising ethylene, ethane, methane and carbon dioxide resulting in a gas stream comprising ethylene, ethane and methane;
(d) passing at least a part of the gas stream comprising ethylene, ethane and methane as obtained in step (c) through a membrane to obtain a stream comprising ethane and methane and a stream comprising ethylene and ethane;
(eA) feeding the stream comprising ethane and methane as obtained in step (d) to a Pressure Swing Adsorption (PSA) unit to obtain a stream comprising ethane and a stream comprising methane; and
(fA) optionally feeding at least a part of the stream comprising methane as obtained in step (eA) to step (a).

5. The process according to claim 4 , wherein step (d) is followed by the following steps:
(gA) passing at least a part of the stream comprising ethylene and ethane as obtained in step (d) through a second membrane to obtain a stream comprising ethane and ethylene and a stream comprising ethylene; and
(hA) optionally feeding at least a part of the stream comprising ethane and ethylene as obtained in step (gA) to the membrane used in step (d), that is to say to the first membrane, or optionally feeding at least a part of the stream comprising ethane and ethylene as obtained in step (gA) to step (a).

6. The process according to claim 5 , wherein the second membrane comprises metal cations.

7. The process according to claim 6 , wherein the second membrane comprises silver(I) ions (Ag + ions) or copper(I) ions (Cu + ions).

8. The process according to claim 4 , wherein step (d) is further followed by:
(gB) feeding the stream comprising ethylene and ethane as obtained in step (d) to a distillation column to obtain a stream comprising ethane and a stream comprising ethylene; and
(hB) optionally feeding at least a part of the stream comprising ethane as obtained in step (gB) to step (a).

9. A process for oxidative coupling of methane (OCM), comprising the steps of:
(a) contacting, in a reactor, oxygen and methane with an OCM catalyst, resulting in a reactor effluent comprising ethylene, ethane, methane, carbon dioxide and water;
(b) cooling the reactor effluent to obtain a liquid stream comprising water and a gas stream comprising ethylene, ethane, methane and carbon dioxide;
(c) removing carbon dioxide from at least a part of the gas stream comprising ethylene, ethane, methane and carbon dioxide resulting in a gas stream comprising ethylene, ethane and methane, wherein at least a part of the gas stream comprising ethylene, ethane and methane is subjected to distillation, resulting in a stream comprising methane and a stream comprising ethylene, ethane and methane,
(d)passing at least a part of the gas stream comprising ethylene, ethane and methane as obtained in step (c) through a membrane to obtain a stream comprising ethane and methane and a stream comprising ethylene and ethane;
(eA) feeding the stream comprising ethane and methane as obtained in step (d) to a Pressure Swing Adsorption (PSA) unit to obtain a stream comprising ethane and a stream comprising methane;
(fA) optionally feeding at least a part of the stream comprising methane as obtained in step (eA) to step (a); and
(gC) optionally feeding at least a part of the stream comprising methane as obtained in the distillation to step (a).

10. A process for oxidative coupling of methane (OCM), comprising the steps of:
(a) contacting, in a reactor, oxygen and methane with an OCM catalyst, resulting in a reactor effluent comprising ethylene, ethane, methane, carbon dioxide and water;
(b) cooling the reactor effluent to obtain a liquid stream comprising water and a gas stream comprising ethylene, ethane, methane and carbon dioxide;
(c) removing carbon dioxide from at least a part of the gas stream comprising ethylene, ethane, methane and carbon dioxide resulting in a gas stream comprising ethylene, ethane and methane, wherein at least a part of the gas stream comprising ethylene, ethane and methane is fed to a first Pressure Swing Adsorption (PSA) unit, resulting in a stream comprising methane and a stream comprising ethylene, ethane and methane stream is fed to step (d);
(d) passing at least a part of the gas stream comprising ethylene, ethane and methane as obtained in step (c) through a membrane to obtain a stream comprising ethane and methane and a stream comprising ethylene and ethane;
(eA) feeding the stream comprising ethane and methane as obtained in step (d) to a second PSA unit to obtain a stream comprising ethane and a stream comprising methane;
(fA) optionally feeding at least a part of the stream comprising methane as obtained in step (eA) to step (a); and
(gC) optionally feeding at least a part of the stream comprising methane as obtained in the first PSA step to step (a).

11. A process for oxidative coupling of methane (OCM), comprising the steps of:
(a) contacting, in a reactor, oxygen and methane with an OCM catalyst, resulting in a reactor effluent comprising ethylene, ethane, methane, carbon dioxide and water;
(b) cooling the reactor effluent to obtain a liquid stream comprising water and a gas stream comprising ethylene, ethane, methane and carbon dioxide;
(c) removing carbon dioxide from at least a part of the gas stream comprising ethylene, ethane, methane and carbon dioxide resulting in a gas stream comprising ethylene, ethane and methane, wherein at least a part of the gas stream comprising ethylene, ethane and methane is fed to a

Assignees

• Shell Oil Co

Inventors

• Mitkidis Georgios

Classifications

• C07C2/84 Primary

  catalytic · CPC title

• B01D3/145

  One step being separation by permeation · CPC title

• B01D2257/7025

  Methane · CPC title

• B01D2252/10

  Inorganic absorbents · CPC title

• Y02C20/40

  of CO2 · CPC title