Ceramic membranes are receiving increasing attention as ultrafiltration materials in pollution prevention resource recovery and waste treatment due to their high strength and tolerance to extreme conditions involving solvent pH oxidation and temperature. Conventional sol-gel routes to alumina-based membranes and filters suffer from poor control of resulting pore sizes and distribution. Because membrane selectivity is primarily dependent on these factors this drawback affects the performance of the materials in ultrafiltration applications that often demand pore sizes down to 2mn. Pore sizes of this diameter however can also decrease the efficiencies of the membranes by inhibiting flow through of solutions. Efficiency can be improved be increasing the macroscopic surface area of the membrane. Solution:One strategy for increasing the surface area is the deposition of hollow spheres within the membrane. The present invention describes the creation of a hierarchical ultrafiltration membrane that incorporates hollow spheres for improved flow and permeability characteristics at small pore sizes. Thin membranes deposited with alumina spheres achieved increased flow relative to the corresponding “flat” membrane. The incorporated spheres also display exceptional strength and can be doped with various transition metals. Development and Licensing Status: This technology is available for licensing on a non-exclusive basis from Rice University. Market Potential/Applications:Lux Research projects the market for membrane-based water treatment technologies to increase to $2.8 billion by 2020. Areas for application include desalination municipal water recycling and waste water treatment. Ultrafiltration membranes could also find utility in treating water generated in oil and gas production.
(1) Single-step alternative to sol-gel methods for producing membranes(2) Synthesis of alumina spheres is simple and cost effective (3) Increased membrane surface area results in increases in efficiency