Original Installation for Researching the Process of Forming Polysulfone Hollow Fiber Membranes

2021 ◽  
Vol 899 ◽  
pp. 1-8
Author(s):  
Tatiana S. Anokhina ◽  
A.Yu. Raeva ◽  
Ilya L. Borisov
Keyword(s):  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Polymer Concentration ◽  
Hollow Fiber Membranes ◽  
Selective Layer ◽  
Molding Method ◽  
Fiber Wall ◽  
Wide Range ◽  
Fiber Membranes ◽  
The Relationship

In this work an original installation (manipulator) has been created that allows one to obtain up to 30 samples of hollow fiber membranes in one molding cycle, while simultaneously varying the molding conditions in a wide range (polymer concentration, nature of solvent and precipitant, exposure time in air and in a precipitant environment, post-processing and washing modes samples, diameter of the carrier needle). This installation makes it possible to move to a fundamentally higher level of accumulation of experimental data on the relationship "the composition of the spinning solution - the structure of the hollow fiber membrane - the separating properties of the membrane." It will also make it possible to involve in these studies new laboratory samples of polymers whose synthesis volumes are insufficient for the existing methods of obtaining laboratory samples of hollow fiber membranes. The principle of operation of the manipulator was worked out when obtaining mini-samples of hollow fiber PSF membranes from 24 wt. % PSF solution in NMP with the addition of 19 wt. % PEG-400 blowing agent on a carrier needle with external deposition. Mini-samples were obtained for studies of morphology, mechanical, transport and separation properties in one molding cycle of the manipulator. The properties of mini-samples of hollow fiber PSF membrane were compared with the properties of a membrane made by the method of “dry-wet” molding with internal deposition from a solution of the same composition. It was found that the porous structures of the membranes differ significantly from each other. In a hollow fiber PSF membrane obtained on a manipulator, the porous structure was spongy with separate macrovoids of various shapes. However, in the membrane obtained by the “dry-wet” method, a dense selective layer was formed on the inner side of the backing layer of elongated finger-shaped pores. It is the formation of spongy pores along the entire perimeter of the fiber wall that led to a decrease in the permeability of the hollow fiber PSF membrane obtained on the manipulator. Thus, not only the composition of the solution, but also the molding method makes a significant contribution to the properties of the membrane.

scholarly journals Fabrication of Manganese Oxide/PTFE Hollow Fiber Membrane and Its Catalytic Degradation of Phenol

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3651
Author(s):  
Yan Wang ◽  
Diefei Hu ◽  
Zhaoxia Zhang ◽  
Juming Yao ◽  
Jiri Militky ◽  
...  
Keyword(s):  
Manganese Oxide ◽  
Hollow Fiber ◽  
Photoelectron Spectroscopy ◽  
Hollow Fiber Membrane ◽  
Weak Acid ◽  
Environmental Pollutant ◽  
Catalytic Degradation ◽  
Hollow Fiber Membranes ◽  
Fiber Membrane ◽  
Fiber Membranes

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.

scholarly journals Polymeric Hollow Fibers: State of the Art Review of Their Preparation, Characterization and Applications in Different Research Areas

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
K.C. Khulbe ◽  
C. Feng ◽  
T. Matsuura ◽  
M. Khayet
Keyword(s):  
Hollow Fiber ◽  
Manufacturing Industry ◽  
Hollow Fiber Membrane ◽  
Waste Water Treatment ◽  
Hollow Fibers ◽  
Hollow Fiber Membranes ◽  
Seawater Desalination ◽  
Fiber Morphology ◽  
Fiber Technology ◽  
Fiber Membranes

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.

Structure Morphology of Polyethersulfone Hollow Fiber Membrane via Immersion Precipitation Phase Inversion Process

2012 ◽  
Vol 152-154 ◽  
pp. 574-578 ◽  
Author(s):  
Ping Lan ◽  
Wei Wang
Keyword(s):  
Hollow Fiber ◽  
Phase Inversion ◽  
Hollow Fiber Membrane ◽  
Pure Water ◽  
Water Flux ◽  
Additive Concentration ◽  
Hollow Fiber Membranes ◽  
Fiber Membrane ◽  
Fiber Membranes ◽  
And Performance

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.

scholarly journals PVDF/PVDF-g-PACMO blend hollow fiber membranes for hemodialysis: preparation, characterization, and performance

RSC Advances ◽  
2017 ◽  
Vol 7 (43) ◽  
pp. 26593-26600 ◽  
Author(s):  
Zihan An ◽  
Rui Xu ◽  
Fengying Dai ◽  
Gaojian Xue ◽  
Xiaoling He ◽  
...  
Keyword(s):  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Hollow Fiber Membranes ◽  
Fiber Membrane ◽  
Novel Approach ◽  
Fiber Membranes ◽  
And Performance

A novel approach to improve the biocompatibility of PVDF hollow fiber membrane by blending PVDF-g-PACMO copolymer for hemodialysis is provided.

A MORPHOLOGICAL STUDY OF NICKEL OXIDE HOLLOW FIBER MEMBRANES: EFFECT OF AIR GAP & SINTERING TEMPERATURE

2016 ◽  
Vol 78 (12) ◽  
Author(s):  
Mohd Izzat Iqbal Mohd Zahar ◽  
Mohd Hafiz Dzarfan Othman ◽  
Mukhlis A Rahman ◽  
Juhana Jaafar ◽  
Siti Khadijah Hubadillah
Keyword(s):  
Mechanical Strength ◽  
Nickel Oxide ◽  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Air Gap ◽  
Hollow Fibers ◽  
Asymmetric Structure ◽  
Hollow Fiber Membranes ◽  
Fiber Membrane ◽  
Fiber Membranes

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. 

scholarly journals Effective Parameters on Fabrication and Modification of Braid Hollow Fiber Membranes: A Review

Membranes ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 884
Author(s):  
Azadeh Nazif ◽  
Hamed Karkhanechi ◽  
Ehsan Saljoughi ◽  
Seyed Mahmoud Mousavi ◽  
Hideto Matsuyama
Keyword(s):  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
High Surface ◽  
High Surface Area ◽  
Hollow Fiber Membranes ◽  
Fiber Membrane ◽  
Effective Parameters ◽  
Fiber Membranes ◽  
Aeration Process ◽  
Fabrication Parameters

Hollow fiber membranes (HFMs) possess desired properties such as high surface area, desirable filtration efficiency, high packing density relative to other configurations. Nevertheless, they are often possible to break or damage during the high-pressure cleaning and aeration process. Recently, using the braid reinforcing as support is recommended to improve the mechanical strength of HFMs. The braid hollow fiber membrane (BHFM) is capable apply under higher pressure conditions. This review investigates the fabrication parameters and the methods for the improvement of BHFM performance.

scholarly journals Fabrication of Defect-Free P84® Polyimide Hollow Fiber for Gas Separation: Pathway to Formation of Optimized Structure

Membranes ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 4 ◽  
Author(s):  
Miren Etxeberria-Benavides ◽  
Oguz Karvan ◽  
Freek Kapteijn ◽  
Jorge Gascon ◽  
Oana David
Keyword(s):  
Hollow Fiber ◽  
Theoretical Study ◽  
Solvent Mixture ◽  
Fine Tuning ◽  
Hollow Fiber Membranes ◽  
Selective Layer ◽  
Fiber Membranes ◽  
Additional Defect ◽  
Fiber Manufacturing ◽  
Treatment Step

The elimination of the additional defect healing post-treatment step in asymmetric hollow fiber manufacturing would result in a significant reduction in membrane production cost. However, obtaining integrally skinned polymeric asymmetric hollow fiber membranes with an ultrathin and defect-free selective layer is quite challenging. In this study, P84® asymmetric hollow fiber membranes with a highly thin (~56 nm) defect-free skin were successfully fabricated by fine tuning the dope composition and spinning parameters using volatile additive (tetrahydrofuran, THF) as key parameters. An extensive experimental and theoretical study of the influence of volatile THF addition on the solubility parameter of the N-methylpyrrolidone/THF solvent mixture was performed. Although THF itself is not a solvent for P84®, in a mixture with a good solvent for the polymer, like N-Methyl-2-pyrrolidone (NMP), it can be dissolved at high THF concentrations (NMP/THF ratio > 0.52). The as-spun fibers had a reproducible ideal CO2/N2 selectivity of 40, and a CO2 permeance of 23 GPU at 35 °C. The fiber production can be scaled-up with retention of the selectivity.

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