Preparation of Highly Permeable Al2O3 Hollow Fiber Membrane via Phase Inversion Method with Ethanol as External Coagulant

2011 ◽  
Vol 412 ◽  
pp. 203-206 ◽  
Author(s):  
Xiao Zhen Zhang ◽  
Jian Er Zhou ◽  
Yu Hua Jiang ◽  
Jing Zhang

Highly permeable porous alumina (Al2O3) hollow fiber membranes have been developed by a combined phase inversion and sintering technique. Ethanol substituting for water was used as the external coagulant in order to prepare Al2O3 hollow fiber membranes with low trans-membrane resistance. The prepared Al2O3 membranes show a special asymmetric structure with an outer skin layer, highly porous inner surface and sub-layer composed of long and large finger-like pores. The influences of sintering temperature on the average pore size, N2 permeability and bending strength were investigated. Results show that Al2O3 hollow fiber membranes with higher permeability can be prepared using ethanol as the external coagulant. The prepared Al2O3 hollow fiber membranes show a N2 permeability of 871.5 m3·m-2·h-1·bar-1 and a bending strength of 91.4 MPa when sintered at 1550°C for 5h.

2021 ◽  
Vol 899 ◽  
pp. 451-455
Author(s):  
Dmitry N. Matveev ◽  
Vladimir P. Vasilevsky

The design and dimensional characteristics of the spinneret affect not only the geometry of the hollow fiber, but also the transport properties of the hollow fiber membranes. In the literature available today, there is a limited number of works in which the influence of the design and dimensional characteristics of the spinneret is studied. In this work, using the example of polysulfone hollow fiber membranes, it was shown that the use of a spinneret with smaller annular diameters leads to an increase in the gas permeability of the hollow fiber membrane with a decrease in the value of the ideal selectivity for the He/CO2 gas pair. It was found that using the spinneret with large annular diameters, the hollow fiber membrane is obtained with a smaller value of the average pore size of the flow, which is in agreement with the obtained data on gas permeability.


2012 ◽  
Vol 152-154 ◽  
pp. 574-578 ◽  
Author(s):  
Ping Lan ◽  
Wei Wang

Polyethersulfone (PES) hollow fiber membranes have been widely used in many fields, such as ultrafiltration, microfiltration, reverse osmosis, liquid/liquid or liquid/solid separation, gas separation, hemodialysis, and so on. In this paper, the sheet PES hollow fiber membranes were prepared. The morphology and performance of membranes can be controlled. By studying the influence of the compositions and conditions on the morphology and performance of PES hollow fiber membrane, the relationship of morphology and performance of the membrane is acquired. The additives were used such as glycerol, BuOH and PEG. In addition, immerse phase inversion was used as membranes preparation method. The morphology of the membrane was controlled by changing kinds of additive, concentration of additive and so on. It was found that the membrane morphologies were changed by additive obviously. Porosity , pure water flux, scanning electron microscopy(SEM) were used to characterize the morphology and performance of the membranes.


2016 ◽  
Vol 78 (12) ◽  
Author(s):  
Mohd Izzat Iqbal Mohd Zahar ◽  
Mohd Hafiz Dzarfan Othman ◽  
Mukhlis A Rahman ◽  
Juhana Jaafar ◽  
Siti Khadijah Hubadillah

A systematic study of the air gap effects on morphology and mechanical strength of Nickel Oxide (NiO) hollow fiber membranes has been carried out. The hollow fibers were prepared using the dry-jet wet spinning process using a dope solution containing NiO/N-methyl-2-pyrrolidone (NMP)/Arlacel/Poly(ethylene sulphide) with a weight ratio of 70/22.9/0.1/7. Tap water was used as internal and external coagulants. The cross-sectional structure of precursors hollow fiber membrane was studied by scanning electron microscopy (SEM). The results showed that both inner and outer finger-like voids of the hollow membrane were determined by the air gap distance. Experimental results indicated that an increase in air gap distance, from 100 mm to 200 mm, gave a hollow fiber with a lower mechanical strength and higher percentages of cross section surface area covered by finger-like voids structures. This study also revealed that the air gap introduced an elongation stress because of gravity on the internal or external surfaces of the NiO hollow fibers. A more effective hollow fiber membrane which is in asymmetric structure instead of symmetric structure can be produced by using air gap higher than 200 mm. 


2018 ◽  
Vol 14 (3) ◽  
pp. 343-347 ◽  
Author(s):  
Sumarni Mansur ◽  
Mohd Hafiz Dzarfan Othman ◽  
Ahmad Fauzi Ismail ◽  
Muhammad Nidzhom Zainol Abidin ◽  
Noresah Said ◽  
...  

Asymmetric, porous ultrafiltration polysulfone (PSf) hollow fiber membranes were fabricated via the dry-wet phase inversion spinning technique specifically for haemodialysis membrane. The objective was to discover the suitable spinning condition for the fabrication of ultrafiltration hollow fiber membrane with desired sponge-like structure. During haemodialysis procedure, uremic toxins such as urea and creatinine range from size 10,000-55,000 Da needs to be excreted out from the blood. While, proteins such as albumin (66,000 Da) need to be retained. The physical structure or morphology of a fabricated membrane is a major concern in determining the efficiency of a dialysis membrane. Different type of membrane morphology will give a different result in term of its permeability and clearance efficiency. The phase inversion spinning technique is suitable in producing ultrafiltation (UF) membrane where the average pore size of the fabricated membrane is in the range of 0.001 – 0.1 µm. However, there is many factors need to be controlled and manipulated in the phase inversion technique. In this study, the effect of the PVP on membrane pore size and performances were analysed. The contact angle measurement was measured to determine the hydrophilicity of the fibers. The hydrophilic polymer is favorable to avoid fouling and increase its biocompatibility. Furthermore, the diameter of the hollow fibers was determined using a scanning electron microscope (SEM). The effects of different morphology of the hollow fibers on the performance of the membranes were evaluated by pure water flux and BSA rejection. Both techniques were tested using permeation flux system. Based on the results obtained, it is found that the finger-like macrovoids in PSf hollow fiber membranes were suppressed by adding 8% PVP (Mw of 360 kDa) into the spinning dope solution as the result of a drastic increase in dope viscosity. On top of that, fiber spun with 8% PVP show more porous structure which contribute to higher permeability of the membrane. The result of this study can benefit to the membrane field of research especially in membrane technology for haemodialysis application.


2017 ◽  
Vol 11 (1) ◽  
Author(s):  
N. Bolong ◽  
A. F. Ismail ◽  
M. R. Salim ◽  
D. Rana ◽  
T. Matsuura

Novel charged–surface modifying macromolecules (cSMMs) were synthesized and incorporated into polyethersulfone(PES) hollow fiber membranes for water separation application. The macromolecules were synthesized with diisocynate, polypropylene oxide and poly(ethylene glycol)–hydroxybenzene sulfonate (PEG–HBS). In this study, the surface of polyethersulfone hollow fiber membranes prepared by the phase inversion method was modified using 1 wt.% of SMM and 22 wt.% PES concentration in the polymer casting solution. The effect of cSMM on PES hollow fiber membrane modification was investigated. Elemental analysis shows enrichment of oxygen and sulfone on the modified PES membrane bulk properties. In addition, the glass transition temperature confirms the miscibility of the cSMM in PES. Important relations between surface characteristics due to SMM modification with the PES membrane for water separation performance with respect to XPS characterization also highlighted.


Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3651
Author(s):  
Yan Wang ◽  
Diefei Hu ◽  
Zhaoxia Zhang ◽  
Juming Yao ◽  
Jiri Militky ◽  
...  

P-aminophenol is a hazardous environmental pollutant that can remain in water in the natural environment for long periods due to its resistance to microbiological degradation. In order to decompose p-aminophenol in water, manganese oxide/polytetrafluoroethylene (PTFE) hollow fiber membranes were prepared. MnO2 and Mn3O4 were synthesized and stored in PTFE hollow fiber membranes by injecting MnSO4·H2O, KMnO4, NaOH, and H2O2 solutions into the pores of the PTFE hollow fiber membrane. The resultant MnO2/PTFE and Mn3O4/PTFE hollow fiber membranes were characterized using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and thermal analysis (TG). The phenol catalytic degradation performance of the hollow fiber membranes was evaluated under various conditions, including flux, oxidant content, and pH. The results showed that a weak acid environment and a decrease in flux were beneficial to the catalytic degradation performance of manganese oxide/PTFE hollow fiber membranes. The catalytic degradation efficiencies of the MnO2/PTFE and Mn3O4/PTFE hollow fiber membranes were 70% and 37% when a certain concentration of potassium monopersulfate (PMS) was added, and the catalytic degradation efficiencies of MnO2/PTFE and Mn3O4/PTFE hollow fiber membranes were 50% and 35% when a certain concentration of H2O2 was added. Therefore, the manganese oxide/PTFE hollow fiber membranes represent a good solution for the decomposition of p-aminophenol.


Author(s):  
K.C. Khulbe ◽  
C. Feng ◽  
T. Matsuura ◽  
M. Khayet

In this article an attempt is made to review critically the papers published recently on polymeric hollow fibers and hollow fiber membranes. Hollow fiber membranes emerged in early nineteen sixties at almost the same time as the announcement of the cellulose acetate reverse osmosis membrane for seawater desalination by Loeb and Sourirajan. Since then, the hollow fiber technology has progressed along with the industrial membrane separation processes. Today, hollow fiber membranes are being used in every sector of the manufacturing industry, including gas and vapor separation, seawater desalination and waste water treatment. The fabrication of a hollow fiber membrane with a desirable pore–size distribution and performance is not an easy task. There are many factors controlling fiber morphology during the phase inversion process and, at present, we are not able to say that we fully understand the phenomena involved in the fabrication of hollow fibers. Nevertheless, there has been a large amount of knowledge accumulated during the past fifteen years, which has been supported by an equally large amount of efforts by many researchers. This paper attempts to summarize those works. The authors could however look into only those reports which have appeared in scientific journals and few patents, and they are fully aware that there must be much more information that has not surfaced to the journal publication. It is also the authors’ intention to show the future direction including the research topics that have been studied only little or not at all.


2012 ◽  
Vol 421-422 ◽  
pp. 8-14 ◽  
Author(s):  
Jianfeng Yao ◽  
Kun Wang ◽  
Manrui Ren ◽  
Jefferson Zhe Liu ◽  
Huanting Wang

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