Patent ID: 9321694
Filing Date: 2016-04-26
CPC Classification: B01J,C04B

Claim Text:
1. A method of forming a porous discriminating layer on a ceramic support having at least one porous wall comprising (a) establishing a flow of a gas stream containing entrained high porosity aggregates consisting of a solid ceramic or solid ceramic precursor through said at least one porous wall from a gas entry side of said at least one porous wall to a gas outlet side of said at least one porous wall, such that at least a portion of the high porosity aggregates deposit to form a deposited layer of high porosity aggregates on the gas entry side of said at least one porous wall, wherein (1) the high porosity aggregates consisting of ceramic fibers having a diameter of from 1 nanometer to 5 microns that are bonded together at points of contact or entangled together and have a largest dimension from 10 to 500 microns, (2) the high porosity aggregates have a porosity of at least 50 volume-% and an apparent volume average pore diameter, as measured by mercury porosimetry, of no greater than 10 microns and (3) said deposited layer extends only partially through the thickness of said at least one porous wall and (b) calcining said deposited layer to form the porous discriminating layer.