Effect of TEP content in cooling bath on porous structure, crystalline and mechanical properties of PVDF hollow fiber membranes

Abstract Multi-bore hollow fiber membranes were prepared through phase inversion spinning process using new locally designed spinnerets of various geometrical shapes. The spun cylindrical-like, rectangular or ribbon-like, and triangular-like are prepared, dried, and characterized by scanning electronic microscope. Fibers of circular (seven, five, and four bores) shape, rectangular of five bores, and triangular of three bores were chosen to study the effect of both geometrical configuration and the number of bores on the amorphous structure and the mechanical properties of the membranes. Membrane geometry, surface amorphous, and bore arrangements are very sensitive to the operating conditions, especially the extrusion and drawing rates. Three polymeric blends of different compositions are used to prepare multi-bore hollow fiber membranes. This study revealed that the blend composition of PES 16%, PVP 2%, PEG 2%, diethylene glycol 2%, and NMP 78% gives excellent mechanical properties. Optimization of the preparation conditions also developed, where the dope flow rate, the bore flow rate, and the air gap were 1.14 cm3 s−1, 1.1 cm3 s−1, and 0 cm, respectively. Furthermore, this study proved that the circular arrangement has high mechanical strength. The prepared seven-MBHF membranes were applied in the membrane distillation process, a solution of 35 g/l NaCl was used to test the membrane performance, and the achieved flux and rejection were 28.32 L/m2 h and 98.9%, respectively. This performance demonstrated that the prepared membrane in this way is suitable to compete with conventional reverse osmosis technology that uses single track hollow fibers.

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Influence of Spinning Conditions on the Morphology, Pore Size, Pore Size Distribution, Mechanical Properties, and Performance of PVC Hollow Fiber Membranes

Separation Science and Technology ◽

10.1080/01496395.2012.681746 ◽

2012 ◽

Vol 48 (2) ◽

pp. 234-245 ◽

Cited By ~ 3

Author(s):

Qusay F. Alsalhy

Keyword(s):

Mechanical Properties ◽

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Hollow Fiber ◽

Hollow Fiber Membranes ◽

Fiber Membranes ◽

And Performance

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Tailoring the porous structure of hollow fiber membranes for osmotic power generation applications via thermally assisted nonsolvent induced phase separation

Journal of Membrane Science ◽

10.1016/j.memsci.2019.03.004 ◽

2019 ◽

Vol 579 ◽

pp. 329-341 ◽

Cited By ~ 7

Author(s):

Young Hoon Cho ◽

Sang Deuk Kim ◽

Jeong F. Kim ◽

Hyeon-gyu Choi ◽

Youngmi Kim ◽

...

Keyword(s):

Power Generation ◽

Phase Separation ◽

Porous Structure ◽

Hollow Fiber ◽

Hollow Fiber Membranes ◽

Fiber Membranes

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New Express Method of Non-Destructive Controlling of the Porous Structure of Asymmetric Membranes

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.899.456 ◽

2021 ◽

Vol 899 ◽

pp. 456-462

Author(s):

Dmitry N. Matveev ◽

Ilya L. Borisov ◽

Vladimir P. Vasilevsky

Keyword(s):

Electric Field ◽

Porous Structure ◽

Hollow Fiber ◽

Polymer Membranes ◽

Average Intensity ◽

Hollow Fiber Membranes ◽

Express Method ◽

Inhomogeneous Electric Field ◽

Fiber Membranes ◽

Non Destructive

An important practical and fundamental problem in the production of porous polymer membranes is the study of the porous structure and the detection of "defects" or large pores in the area of the membrane. Known porosimetry methods cannot solve this problem. This work proposes a new non-destructive express method for studying the porous structure of asymmetric polymer membranes in high-intensity electric fields. This method can be successfully implemented on both flat sheet and hollow fiber membranes with a known porous structure. On the example of hollow fiber membranes made of polyacrylonitrile and polysulfone an assessment of the chemical structure effect of the membrane material on the high-voltage discharge currents in a highly inhomogeneous electric field through hollow fiber membranes with a given pore size was made. Under normal conditions and an average intensity of an inhomogeneous electric field E = 5 kV/cm, the results obtained allow us to conclude about a certain practical potential of the developed express method.

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