A CO2-stable hollow-fiber membrane with high hydrogen permeation flux

The particles from carwash wastewater were separated by a hollow fiber membrane aided by a enhanced coagulation and activated carbon. This study demonstrated that the addition of KMnO4 to coagulant (PAC) could enhance the efficiency of coagulation, which helped reduce clogging of the ultrafiltration membrane and activated carbon. The existence of LAS can loosen the gel layer on the membrane and improve the flux. Adsorption of particles such as organic matter and oil is the main reason causing membrane flux decrease. When carwash wastewater was pretreated, the permeation flux of membrane showed a higher value. LAS, odour and colour are removed by GAC adsorption treatment at last. The COD, BOD, LAS and oil of reuse water was 33.4 mg/L, 4.8 mg/L, 0.06 mg/L and 0.95 mg/L, respectively.

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One-Step Thermal Processing of BaCe0.8Y0.2O3-δ Hydrogen Permeable Multi-Channel Hollow Fiber Membrane

10.22541/au.163253495.50334833/v1 ◽

2021 ◽

Author(s):

Tianlei Wang ◽

Zheng Fan ◽

Shoufei Wang ◽

Qiankun Zheng ◽

Jinkun Tan ◽

...

Keyword(s):

Hollow Fiber ◽

Thermal Processing ◽

Hydrogen Permeation ◽

Sintering Temperature ◽

Hollow Fiber Membrane ◽

Fiber Membrane ◽

Barium Cerate ◽

Long Term Stability ◽

Fiber Fabrication ◽

One Step

Yttrium-doped barium cerate (BaCeYO, BCY) is the most widely studied proton conducting material and is frequently fabricated as dense membranes for hydrogen separation. However, the difficulty to prepare dense BCY membranes is the extremely high sintering temperature, normally higher than 1500 oC. Herein, the BCY 7-channel hollow fiber membrane was prepared by one-step thermal processing (OSTP). It proved that adding CoO as sintering aid is beneficial to the densification and 1wt% CoO was the optimum addition to form a homogeneous phase structure. The dense sintering temperature was greatly reduced from over 1500 to 1350 C. The hydrogen permeation flux of the BCY hollow fiber membrane reached up to 0.34 ml mincm at 900 C. The long-term stability test last for 300 h. The properties of OSTP samples were demonstrated to be essentially higher than samples made by conventional ceramic hollow fiber fabrication methods.

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Recent Progress in Charged Polymer Chains Grafted by Radiation-Induced Graft Polymerization; Adsorption of Proteins and Immobilization of Inorganic Precipitates

Quantum Beam Science ◽

10.3390/qubs4020020 ◽

2020 ◽

Vol 4 (2) ◽

pp. 20 ◽

Cited By ~ 1

Author(s):

Ryo Ishihara ◽

Shiho Asai ◽

Kyoichi Saito

Keyword(s):

Hollow Fiber ◽

Graft Polymerization ◽

Hollow Fiber Membrane ◽

Pure Water ◽

Polymer Chains ◽

Permeation Flux ◽

Fiber Membrane ◽

Polymer Substrates ◽

Radiation Induced ◽

Charged Polymer

Radiation-induced graft polymerization provides industrially superior functionalization schemes by selection of existing polymer substrates and design of graft chains. In this review, by a pre-irradiation method of the radiation-induced graft polymerization and subsequent chemical modifications, charged polymer chains grafted onto various components and shapes of the polymer substrates are described. The charged graft chains immobilized onto a porous hollow-fiber membrane captured proteins in multilayers via multipoint binding. A membrane onto which positively charged graft chains are immobilized, i.e., an anion-exchange porous hollow-fiber membrane, was commercialized in 2011 for the removal of undesirable proteins in the purification of pharmaceuticals. On the other hand, a membrane onto which negatively charged graft chains are immobilized, i.e., a cation-exchange porous hollow-fiber membrane, exhibited a low permeation flux for pure water; however, the prepermeation of an aqueous solution of magnesium chloride through the membrane restored the permeation flux because of ionic crosslinking of graft chains with magnesium ions. The charged graft chains provide a precipitation field for inorganic compounds such as insoluble cobalt ferrocyanide. The graft chains entangle or penetrate a precipitate owing to electrostatic interactions with the surface charge on the precipitate. Braids and wound filters composed of insoluble-cobalt-ferrocyanide-impregnated fibers are used for the removal of radiocesium from contaminated water at Tokyo Electric Power Co. (TEPCO) Fukushima Daiichi Nuclear Power Plant.

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Hydrogen Permeation Performance of Ni-BaZr0.1Ce0.7Y0.2O3−δ Metal-Ceramic Hollow Fiber Membrane

Chinese Journal of Chemical Physics ◽

10.1088/1674-0068/25/02/125-128 ◽

2012 ◽

Vol 25 (2) ◽

pp. 125-128 ◽

Cited By ~ 5

Author(s):

Chun-li Yang ◽

Qi-ming Xu ◽

Zhi-wen Zhu ◽

Wei Liu

Keyword(s):

Hollow Fiber ◽

Hydrogen Permeation ◽

Hollow Fiber Membrane ◽

Fiber Membrane ◽

Metal Ceramic

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Membrane vacuum stripping process for volatile organics removal from water using an asymmetric PVDF (polyvinylidene fluoride) hollow fiber membrane module

Water Science & Technology Water Supply ◽

10.2166/ws.2001.0101 ◽

2001 ◽

Vol 1 (5-6) ◽

pp. 65-75

Author(s):

D. Wang ◽

K. Li ◽

W.K. Teo

Keyword(s):

Hollow Fiber ◽

Polyvinylidene Fluoride ◽

Hollow Fiber Membrane ◽

Membrane Module ◽

Solution Temperature ◽

Permeation Flux ◽

Fiber Membrane ◽

Feed Concentration ◽

Water Permeation ◽

Phase Inversion Technique

The vacuum membrane stripping process (VMS) for removing a VOC (trichloroethylene) from water was studied in a polyvinylidene fluoride (PVDF) hollow fiber membrane module containing 187 fibers with a length of 0.59 m. The porous PVDF asymmetric hollow fiber used was prepared by the wet phase inversion technique. The feed solution containing trichloroethylene (TCE) was passed through the lumen of the PVDF hollow fiber. Vapors of TCE and water were transported through the pores of the membrane into the shell side maintained at a sub-atmospheric pressure, and condensed in cold traps. The effects of down-stream pressure, solution temperature, feed concentration, and feed flow rate on TCE removal, TCE permeation flux, water permeation flux and TCE concentration of the permeated solution, as well as the mass transfer coefficient were investigated. The down stream pressure and solution temperature were identified as the major factors to control VOC removal and TCE concentration in the permeate stream. A small amount of the permeated solution with higher TCE concentration was obtained at the temperature of 50°C and pressure of 80 mmHg when about 90% TCE was removed from the water.

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