US 11,772,053 B2 · Carbon molecular sieve membranes containing a group 13 metal and method to make them

Abstract

A carbon molecular sieve (CMS) membrane having improved separation characteristics for separating olefins from their corresponding paraffins is comprised of carbon with at most trace amounts of sulfur and a group 13 metal. The CMS membrane may be made by pyrolyzing a precursor polymer devoid of sulfur in which the precursor polymer has had a group 13 metal incorporated into it, wherein the metal is in a reduced state. The pyrolyzing for the precursor having the group 13 metal incorporated into it is performed in a nonoxidizing atmosphere and at a heating rate and temperature such that the metal in a reduced state (e.g., covalently bonded to carbon or nitrogen or in the metal state).

Claims14

Dependent claims

A process for separating a gas molecule from a feed gas comprised of the gas molecule and at least one other gas molecule, the process comprising:

(i) providing a carbon molecular sieve membrane comprising, carbon, a group 13 metal, and at most a trace amount of sulfur, wherein the group 13 metal is present in a reduced state, and wherein the group 13 metal is present in an amount of 0.5% to 10% by weight of the carbon molecular sieve membrane;
and
(ii) flowing the gas feed through and over said carbon molecular sieve membrane to produce a first permeate stream having an increased concentration of the gas molecule and a second retentate stream having a decreased concentration of the gas molecule,
wherein the gas molecule is propylene and the at least one other gas molecule comprises ethane, and wherein the carbon molecular sieve membrane has a permeance of propylene of at least 10 GPU.

1 more element

Dependencies are inferred from the claim text.

Carbon molecular sieve membranes containing a group 13 metal and method to make them

Life of this patent

Carbon molecular sieve membranes containing a group 13 metal and method to make them

Life of this patent

Abstract

Claims14