US 2019/0169090 A1 · Oxidative Coupling of Methane Process with Enhanced Selectivity to C2+ Hydrocarbons by Addition of H2O in the Feed

Abstract

A process for producing olefins comprising introducing to a reactor a reactant mixture comprising methane, oxygen, and water, wherein the reactor comprises a catalyst, and wherein water is present in the reactant mixture from 0.5 mol % to 20 mol %; allowing the reactant mixture to contact the catalyst and react via an OCM reaction to form a product mixture comprising C2+ hydrocarbons, unreacted methane, and byproducts; wherein C2+ hydrocarbons comprise olefins and paraffins; and wherein the process is characterized by a productivity, a C2+ selectivity, or both that is increased when compared to a productivity, a C2+ selectivity, or both, respectively, of an otherwise similar process conducted (i) with a reactant mixture comprising methane and oxygen and (ii) without water present in the reactant mixture from 0.5 mol % to 20 mol %; recovering the product mixture from the reactor; recovering C2+ hydrocarbons from the product mixture; and recovering olefins from C2+ hydrocarbons.

Claims20

Dependent claims

A process for producing olefins comprising:

(a) introducing a reactant mixture to a reactor, wherein the reactant mixture comprises methane, oxygen, and water, wherein the reactor comprises a catalyst, and wherein the water is present in the reactant mixture in an amount of from about 0.5 mot % to about 20 mol %;
(b) allowing at least a portion of the reactant mixture to contact the catalyst and react via an oxidative coupling of methane (OCM) reaction to form a product mixture;
wherein the product mixture comprises C2+ hydrocarbons, unreacted methane, and byproducts;
Wherein the C2+ hydrocarbons comprise olefins and paraffins;
and wherein the process is characterized by a productivity, a C2+ selectivity, or both that is increased when compared to a productivity, a C2+ selectivity, or both, respectively, of an otherwise similar process conducted (i) with a reactant mixture comprising methane and oxygen and (ii) without the water present in the reactant mixture in an amount of from about 0.5 mol % to about 20 mol %;
(c) recovering at least a portion of the product mixture from the reactor;
(d) recovering at least a portion of the C2+ hydrocarbons from the product mixture;
and
(e) recovering at least a portion of the olefins from the C2+ hydrocarbons.

6 more elements

A process for producing olefins comprising:

(a) introducing a first reactant mixture to a first reactor, wherein the first reactant mixture comprises methane, oxygen, and water, wherein the first reactor comprises a first catalyst, and wherein the water is present in the first reactant mixture in an amount of from about 0.5 mol % to about 20 mol %;
(b) allowing at least a portion of the first reactant mixture to contact the first catalyst and react via an oxidative coupling of ethane (OCM) reaction to form a first product mixture;
wherein the first product mixture comprises C2+ hydrocarbons, unreacted methane, and byproducts;
wherein the C2+ hydrocarbons comprise olefins and paraffins;
and wherein the byproducts comprise carbon monoxide, carbon dioxide, water, and hydrogen;
(c) recovering at least a portion of the first product mixture from the first reactor;
(d) removing a portion of the water from the first product mixture to produce a first intermediate mixture;
(e) introducing a second reactant mixture to a second reactor comprising a second catalyst, wherein the second reactant mixture comprises at least a portion of the first intermediate mixture and oxygen, wherein the second reactant mixture comprises water in an amount of from about 0.5 mol % to about 20 mol %, and wherein the first catalyst and the second catalyst are the same or different;
(f) allowing at least a portion of the second reactant mixture to contact the second catalyst and react via an OCM reaction to form a second product mixture;
wherein the second product mixture comprises C2+ hydrocarbons, unreacted methane, and byproducts;
wherein an amount of unreacted methane in the second product mixture is less than an amount of unreacted methane in the first product mixture;
and wherein an amount of olefins in the second product mixture is greater than an amount of olefins in the first product mixture;
(g) recovering at least a portion of the second product mixture from the second reactor;
(h) optionally removing a portion of the water from the second product mixture to produce a second intermediate mixture;
and
(i) recovering at least a portion of the olefins from the second product mixture and/or the second intermediate mixture.

13 more elements

A system for producing olefins comprising:

(a) a first oxidative coupling of methane (OCM) stage comprising:
(i) a first adiabatic reactor comprising a first catalyst, wherein the first adiabatic reactor is configured to receive a first reactant mixture comprising methane, oxygen, and water, wherein the water is present in the first reactant mixture in an amount of from about 0.5 mol % to about 20 mol %;
and to produce a first product mixture;
wherein the first product mixture comprises C2+ hydrocarbons, unreacted methane, and byproducts;
wherein the C2+ hydrocarbons comprise olefins and paraffins;
and wherein the byproducts comprise carbon monoxide, carbon dioxide, water, and hydrogen;
and
(ii) a first separating unit configured to receive at least a portion of the first product mixture and to produce a first intermediate mixture, wherein an amount of water in the first intermediate mixture is less than an amount of water in the first product mixture;
(b) a second OCM stage comprising:
(iii) a second adiabatic reactor comprising a second catalyst, wherein the second adiabatic reactor is configured to receive a second reactant mixture comprising at least a portion of the first intermediate mixture and oxygen, wherein the water is present in the second reactant mixture in an amount of from about 0.5 mol % to about 20 mol %;
and to produce a second product mixture;
wherein the second product mixture comprises C2+ hydrocarbons, unreacted methane, and byproducts;
wherein an amount of unreacted methane in the second product mixture is less than an amount of unreacted methane in the first product mixture;
and wherein an amount of olefins in the second product mixture is greater than an amount of olefins in the first product mixture;
and
(iv) an optional second separating unit configured to receive at least a portion of the second product mixture and to produce a second intermediate mixture, wherein an amount of water in the second intermediate mixture is less than an amount of water in the second product mixture;
and
(c) a third separating unit configured to receive at least a portion of the second product mixture and/or the second intermediate mixture and to produce olefins.

15 more elements

Dependencies are inferred from the claim text.

Oxidative Coupling of Methane Process with Enhanced Selectivity to C2+ Hydrocarbons by Addition of H2O in the Feed

Life of this patent

Oxidative Coupling of Methane Process with Enhanced Selectivity to C2+ Hydrocarbons by Addition of H2O in the Feed

Life of this patent

Abstract

Claims20