Patent ID: 7959716
Filing Date: 2011-06-14
Classification: B01D,B22F,C01B,C04B,C22C,Y10T

Abstract:
1. A hydrogen permeable membrane on a porous support prepared by: (a) forming a mixture of metal oxide powder and ceramic oxide powder and optionally a pore former; (b) pressing the mixture to form an article; (c) pre-sintering the article at an elevated temperature in air to remove at least some of the pore former if present and to impart mechanical integrity and porosity to the article; and (d) thereafter sintering the article in a reducing atmosphere to reduce metal oxide near the surface of the article to a metal and leave metal oxide in the core of the article, and thereby provide a dense hydrogen permeable portion near the surface of the sintered mixture and a porous core having a lower density relative to the dense surface layer; wherein the dense hydrogen permeable portion has a higher initial concentration of metal than the remainder of the sintered mixture, the metal oxide is selected from the group consisting of oxides of Ni, Pd, Pd alloys, and mixtures thereof, the ceramic oxide is selected from the group consisting of yttria stabilized zirconia, shrinkable alumina, Y doped cerates, Gd doped cerates, titanates, barium zirconates strontium zirconates, and mixtures thereof, and the dense hydrogen permeable portion has a metal concentration in the range of from about 20 to about 80 percent by volume.