Fibers Hollow fiber membranes

Fiber, hollow fiber Membranes, heat exchangers, micro tools, active fiber composites, micro-reactors, fibers for functional or stmc-tural applications... 

Appiications cable insulation, capacitors, coatings (agitators, centrifuges, electroplating equipment, exhaust hoods, filters, piping systems, reactors, semiconductor storage tanks, vessels), films, fibers, hollow fiber membranes, pipes, printed circuits, rods, sheet, solar collectors ... 

Hollow-fiber membranes may be run with shell-side or tube-side feed, cocurrent, countercurrent or in the case of shell-side feed and two end permeate collection, co- and countercurrent. Not shown is the scheme for feed inside the fiber, common practice in lower-pressure separations such as air. 

Nonselective membranes can assist enantioselective processes, providing essential nonchiral separation characteristics and thus making a chiral separation based on enantioselectivity outside the membrane technically and economically feasible. For this purpose several configurations can be applied (i) liquid-liquid extraction based on hollow-fiber membrane fractionation (ii) liquid- membrane fractionation and (iii) micellar-enhanced ultrafiltration (MEUF). 

Fig. 5-10. Schematic representation of hollow-fiber membrane extraction.

Fig. 5-12. Separation of d,1-leucine in hollow-fiber membrane extraction using a Al- -dodecyl-l-hydrox-yproline solution in octanol as the enantioselective extraction liquid. The modules used were 32 cm long and contained 96 Celgard X-20 polypropylene fibers [57].

These gas transfer membranes or membrane contactors employ microporous polypropylene hollow fiber membranes arranged in a modular design. Oxygenated water flows on the shell side of the hollow fibers, and a strip gas (such as nitrogen) or a vacuum is applied to the inside (lumenside), with the hollow fibers acting as a support medium for intimate contact between the water and gas phases. 

In the present study, we fabricated hollow fiber membrane modules and performed experiments at several conditions. The energy consumption of this process is compared to those of conventional gas absorption processes and membrane gas separation processes. 

Nonbiological methods for removal of trichloroethylene from water are also being studied. These include the use of a hollow fiber membrane contactor (Dr. A.K. Zander, Clarkson University), photocatalysis by solar or artificially irradiated semiconductor powders (Dr. G. Cooper, Photo-catalytics, Inc.), and micellar-enhanced ultrafiltration (Dr. B.L. Roberts, Surfactant Associates, Inc.). 

A bench top polysulfone hollow fiber membrane (0.0325m ) with molecular weight cutoff (MWCO) of 30K (A/G Technology Corp., Needham MA) was used (24). UF was run in a total recycle mode at a rate of 1.2 L/min (flow speed of 0.73 m/sec), cross membrane pressure of 25 PSIG and 10 + 1°C. PE permeability is expressed as the fraction of PEU/mL in the permeate to PEU/mL in the retentate. Data presented are representative of at least duplicate replications. 

Cross-flow ultrafdtration equipment.—The device used is shown in Figure 1. It included a glass reactor (R) with temperature, pH and stirring control, a Minitan pump (P) (Millipore, Bedford, USA), a Harp hollow fiber membrane cartridge (M) (Romicon-Supelco, Bellefonte, USA) with a cut-off of 2000 daltons, and a permeate exit (f) for fraction collection. The retentate (r) was returned to the reactor. 

Hollow-fiber membrane reactor Hydrolysis of sunflower oil Lipase from Rhizopus sp. 122... 

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