High‐Performance Ceramic Membranes with a Separation Layer of Metal Oxide Nanofibers

Abstract

Layers of randomly oriented fibers arranged in a hierarchical structure as the separation layer in ceramic membranes (see figure) are shown to greatly improve the separation efficiency compared to conventionally fabricated ceramic membranes, and remove the problems of cracks, pinholes, and serious sintering. The membranes have many potential applications, for example, removing viruses and waterborne pathogens.

Virus Filtration Membranes Prepared from Nanoporous Block Copolymers with Good Dimensional Stability under High Pressures and Excellent Solvent Resistance

“…[3] Membrane-based techniques employing ultrafiltration membranes and track-etched membranes have been widely used for virus filtration due to cost effectiveness and ease of operation. [4][5][6][7][8][9] However, the broad size distribution of pores in ultrafiltration membranes and the low density of pores in track-etched membranes limit the practical use of virus filtration. [6,7] On the other hand, nanoporous membranes prepared by a block copolymer exhibit uniform sizes of pores due to the self-assembly nature.…”

High‐Performance Multifunctional TiO2 Nanowire Ultrafiltration Membrane with a Hierarchical Layer Structure for Water Treatment

“…The membrane separation of gases and liquids can often be more economical and energy effective than traditional separation methods, such as distillation or absorption. [1][2][3][4] Recently, ceramic membranes have attracted considerable attention due to their excellent thermal, chemical, and mechanical stability as compared to polymeric membranes. [5][6][7] Ceramic membranes generally have an unsymmetrical layered structure, consisting of two layers: a supporting and a functional layer (separation layer), while some consist of an additional intermediate layer.…”

“…However, formation of pinholes and cracks within the membrane usually occur during the drying and calcination process. [2] Membrane flux is proportional to the pressure difference across the membrane. As a result, membranes need to able to withstand high pressure and flux, which are inevitable in ultrafiltration (UF) or nanofiltration (NF) processes.…”

“…Theoretically, the mesh structure, as conjugated by 1D materials, should be most efficient for filtration since it provides increased selectivity and flux, due to its high surface porosity and pore density. [2,18] Ke et al lately fabricated a ceramic membrane via a spin-coating and calcination method. The resulting membrane has a pore size of 60 nm and consists of a titanate fiber intermediate layer and alumina fiber separation layer.…”

Synthesis ofβ-SiAlON whiskers: dependence of uniform morphology upon preparation conditions

“…[3][4][5][6][7][8] The use of ceramic whiskers to fabricate ceramic membrane filters is a new direction in developing high performance ceramic membranes. [9][10][11] Compared to oxide whiskers investigated in the literature, nitride whiskers show higher potential application as membrane filters due to their excellent properties, such as high strength, fracture toughness, thermal shock resistance and chemical resistance. 12 Nitride whiskers possess much higher porosity (up to 70%) resulting in higher permeability in filtration than oxide whiskers.…”