Microstructured hollow fibers for ultrafiltration

Estimation of the structure dependent performance of 3-D rapid prototyped membranes

“…Innovative fabrication techniques afford non-circular hollow-fiber membranes with topological features on the in-and outside of the membrane. [28][29][30][31][32][33] Tubular or irregular hollow-fibers can be combined into non-parallel bundles to shape the flow-profile and improve mass transport. [34][35][36][37] These studies indicate that the macroscopic membrane geometry and their arrangement is a key factor to improve mass transport and reduce fouling to boost membrane performance.…”

Fabrication and characterization of hydroxylated and carboxylated multiwalled carbon nanotube/polyethersulfone (PES) nanocomposite hollow fiber membranes

“…In the current work we explore the fabrication and improved mechanical properties of extruded hollow fiber ultrafiltration membranes composed of PES-CNTs. Desalination 359 (2015) [123][124][125][126][127][128][129][130][131][132][133][134][135][136][137][138][139][140] In hollow fiber fabrication, commonly used polymers for ultrafiltration include polyethersulfone (PES) [9,[13][14][15][16], polyvinylidene fluoride (PVDF) [8,17], polyacrylonitrile (PAN) [18], and polysulfone (PS) [19][20][21]; solvents [5,22] include N-N-dimethylformamide (DMF) and 1-methyl-2-pyrrolidone (NMP); and the most common additives [5,14,[23][24][25] are polyvinylpyrrolidone (PVP), and polyethylenegylcol (PEG). The hollow fiber spinning process depends on several parameters, including air gap length [26,27], dope solution viscosity [28], dope extrusion rate [29][30][31], coagulation bath temperature and composition [15,32], take-up speed [33], and bore and outer fluid type [20].…”

“…One strategy for improving the life and performance of membranes is to include nanomaterials such as carbon nanotubes (CNTs) in the membrane matrix [34]. To this end, nanomaterials including silica [8], titania [9], aluminum oxide [35], zinc oxide [36], silver [37][38][39], copper, selenium [40] as well as carbon nanotubes [34,[41][42][43] have been used to form nanocomposite membranes. However, fabrication of hollow fiber membranes made from nanomaterial-polymer composites present many challenges given the number of variables involved in optimizing hollow fiber formation and the potentially related effects of nanomaterials present in the polymer solution on the phase inversion process.…”

Three-dimensional hydraulic modeling of particle deposition on the patterned isopore membrane in crossflow microfiltration

“…Patterned membranes with various configurations and shapes have been prepared and tested. Patterned hollow-fiber membranes were fabricated from patterned nozzles and showed increased water flux compared with conventional hollow-fiber membranes [3][4][5][6][7]. Prism, pyramid, and embossed patterns were made on a flat sheet membrane surface, and all of them improved anti-fouling properties by inducing local turbulence or increasing wall shear stress at the upper region of pattern [8,9].…”