Silica support structure for a zeolite membrane
A process for making a mechanically strong, high permeance, and relatively inexpensive support structure for zeolite membranes is described. In an example implementation, a process includes forming a silica powder from silica fibers, mixing the silica powder and a polymer solution to form a mixture, forming the mixture into a shaped mixture, and sintering the shaped mixture to form a silica support.
1. A silica support, comprising:
a porous layer of interconnected silica particles suitable for supporting a zeolite membrane;
wherein the layer has a nitrogen permeance in a range of approximately 3×10 −5 to 8×10 −5 mol/m 2 sPa; and
wherein the layer of interconnected silica particles comprises interconnected anisotropic silica fibers.
2. The silica support of claim 1 , wherein the layer of interconnected silica particles has inter-particle gaps that are less than 10 μm.
3. The silica support of claim 1 , wherein each anisotropic silica fiber has an aspect ratio in the range of approximately 2 to 10.
4. The silica support of claim 1 , wherein the silica support has a bi-axial flexural strength of 18.2±0.5 MPa as measured by a ring-on-ring test using two Viton O-rings.