Polysulfone fiber

Hydrogen Hydrogen recovery was the first large commercial membrane gas separation. Polysulfone fiber membranes became available in 1980 at a time when H9 needs were rising, and these novel membranes qiiickly came to dominate the market. Applications include recovery of H9 from ammonia purge gas, and extraction of H9 from petroleum crackiug streams. Hydrogen once diverted to low-quahty fuel use is now recovered to become ammonia, or is used to desulfurize fuel, etc. H9 is the fast gas. 

Trichloroethene 20 Polysulfone fibers Acetate, minerals Yes Sludge 74... 

In early experiments with polysulfone fibers, we included a hydrophilic prepolymer (precursor for the polyurethane employed) in the polysulfone system. It was... 

Monsanto and Ube (Japan) developed membrane processes for purification of hydrogen gas mixtures. This process is based on the selective diffusion of hydrogen through semi-permeable membranes in the form of hollow fibers. The Monsanto PRISM separator process (owned by Air Products as of 2004) uses a polysulfone fiber whereas Ube uses an aromatic polyimide fiber.46... 

Generally, the salt rejections observed for these membranes in seawater reverse osmosis tests did not exceed 80 percent. This process was applied at Albany International to form composite membranes on hollow polysulfone fibers (25). Salt rejections on the hollow fiber membranes were above 98 percent at an average flux of about 1.5 gfd (2.5 L/sq m/hr) in a 12 000-hour test using 30 000 ppm seawater at 1000 psi. In other 5000-hour tests using 3500 ppm brackish water at 400 psi with addition of 100 ppm chlorine at pH 8 flux and salt rejection remained constant at 1 gfd and 98 percent respectively (Figures 8 and 12 in Reference 25 a). 

Assume a polysulfone fiber with an effective thickness of 1000 A and a surface porosity of 10"6 (ratio of pore area to total area). The fiber is coated with a silicone at a thickness of 1 jum. The intrinsic permeabilities of polysulfone and silicone are ... 

Yuan X., Zhang Y., Dong C., and Sheng J., Morphology of ultrafine polysulfone fibers prepared by electrospinning, Polym. Int, 2004, 53, 1704-1710. 

Two types of poly electrolyte nanofiber mats were prepared in this study. One was polyacrylic acid (Mv = 450,000) fibers, spun from 5 wt% of aqueous solution. The other one was polysulfone fibers, spun from 25 wt% of DMF solution. The polysulfone fiber was then coated with a layer of polyelectrolyte, FAMPS, by a surface grafting technique (FAMFS-g-FS) similar to the procedure described previously. Nucrel membranes wereprepared by heat pressing Nucrel 535 (DuPont) pellets at 125°C. For fiber encapsulation, the fiber mats with measured weight and thickness were placed between two preweighed Nucrel membranes and then pressed at 125°C. The resulting composite membranes were flexible and robust with a homogeneous transparency. 

TABLE 20.1-2 Extent of Achievement of Dense-Film Ideal Separation Factors Using Coated High-Flux Asymmetric Polysulfone Fibers... 

Yuan, X. Y., Y. Y. Zhang, C. H. Dong, and J. Sheng (2004). Morphology of ultra-fine polysulfone fibers prepared by electrospinning. Polymer International 53(11) 1704-1710. 

Xu, Z., Gu, Q., Hu, H., Li, R, 2008, A novel electrospun polysulfone fiber membrane Application to advanced treatment of secondary biotreatment sewage. Environ Technol 29(1) 13-21. 

The most widely used chemically modified PPO in the development of thin film composite membranes is sulfonated polyphenylene oxide (SPPO). The polymer in the acid form as well as salt form has been used by Bikson to produce multilayer composite membranes. These types of membranes have been described to have at least two chemically distinct layers deposited on a porous substrate in a single coating step process. The outer layer forms a protective defect-sealing surface whereas the inner layer is the selective SPPO layer. This layer is adjacent to the porous support membrane. The two top layers are formed simultaneously on top of porous polysulfone support hollow fibers. A coating solution of SPPO in the lithium salt form (SPPO-Li ) and amine functional silicone fluid was coated on top of the polysulfone fibers. These coated fibers were used to construct a hollow fiber separator permeator. 

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