Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Thin film composite hollow fiber membranes for osmotic power generation

a technology of osmotic power generation and thin film composite, which is applied in the direction of membranes, filtration separation, separation processes, etc., can solve the problems of adversely affecting the pwp rate, and achieve the effect of high water permeability rate and high pressur

Inactive Publication Date: 2016-05-05
NAT UNIV OF SINGAPORE
View PDF0 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

This patent describes a thin film composite (TFC) hollow fiber that can withstand high pressure while maintaining a high water permeability rate. The TFC hollow fiber has an outer support layer and an inner thin film layer adherent to the support layer. The support layer can be made of polyethersulfone, polysulfone, polyamide-imide, polyamide-imide, polyvinylidene fluoride, cellulose triacetate, polyetherketone, or polyetheretherketone. The inner thin film layer can be made of cross-linked polyamide. The TFC hollow fiber exhibits a transmembrane pressure resistance rate of higher than 15 bar and a pure water permeability rate of higher than 0.8 Lm−2 h−1 bar−1. The patent also describes a method for preparing the support layer of the TFC hollow fiber. The technical effects of this invention include high water permeability and high pressure resistance, making it suitable for use in developing osmotic energy.

Problems solved by technology

Yet, a higher mechanical strength typically requires a higher density or a greater thickness of the membrane, which adversely affects the PWP rate.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Thin film composite hollow fiber membranes for osmotic power generation
  • Thin film composite hollow fiber membranes for osmotic power generation

Examples

Experimental program
Comparison scheme
Effect test

example 1

Preparation of Hollow Fiber PES Supports

[0030]Three hollow fiber supports made of PES, designated as L, MM, and N, were prepared using a triple orifice spinneret as described below.

[0031]A spinning dope containing PES, NMP and, optionally, PEG and water, was first prepared. Listed in Table 1 below are the detailed spinning conditions for preparing these three supports and the parameters of the triple orifice spinneret. Supports L, MM, and N were prepared from different spinning dopes, each of which was made using PES of the same wt %, water of increasing wt % (0.0 to 6.4 wt %), and both PEG and NMP of decreasing wt %. See Table 1, row 3 “Spinning dope composition.” Each of the supports was prepared by extruding NMP through the external orifice of the spinneret to promote high porosity at the outer surface of the support, extruding the spinning dope through the middle orifice, and extruding water, an internal coagulant, through the internal orifice to promote formation of an inner sk...

example 2

Characterization of the Hollow Fiber PES Supports

[0032]Field emission scanning electron microscopy (FESEM) images of support showed diverse morphologies of hollow fiber PES supports L, MM, and N prepared in Example 1. Namely, the cross sections of L, MM, and N all changed from a fully macrovoid structure to a sponge-like structure.

[0033]A study was conducted to characterize L, MM, and N and the results are summarized in Table 2 below.

TABLE 2Characteristics of the hollow fiber PES supportsHollow Fiber PES SupportsLMMNMean pore diameter (nm) 9.32 8.712.25Geometric standard  1.18 1.21 1.28variation, σMWCO34,91731,67284,630Porosity 75.0 ± 0.1 75.3 ± 0.1 74.7 ± 0.1Maximum tensile  4.57 ± 0.24 4.69 ± 0.55 5.33 ± 0.19stress (Mpa)Young's modulus (Mpa)200.44 ± 27.26212.6 ± 15.23251.28 ± 4.81Extension (%) 46.45 ± 3.8749.70 ± 5.21 70.75 ± 4.02Burst pressure (bar)17.822.021.0Estimated burst 19.019.923.9pressure (bar)

[0034]The pore size and pore size distribution of a PES support were measured b...

example 3

Preparation of TFC Hollow Fibers

[0041]A polyamide thin film layer was coated on each of the inner surfaces of PES supports L, MM, and N via the interfacial polymerization reaction between MPD and TMC. The coating was conducted as follows.

[0042]First, a tube, which had a proximal end, a distal end, and a lumen diameter the same as that of the support, was reversibly connected, at its distal end, to one end of the support. Next, an aqueous solution containing MPD 2 wt % was pumped for 3 min from the proximal end of the tube to the support to coat the inner surface of the support, followed by blowing air for 5 min from the proximal end of the tube to the support to remove excess aqueous solution. Finally, a hexane solution containing TMC 0.1 wt % was pumped from the proximal end of the tube to the support to coat the aqueous solution, thereby forming a polyamide thin film layer via interfacial polymerization between MPD and TMC on the inner surface of the support.

[0043]The TFC hollow f...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
Lengthaaaaaaaaaa
Thicknessaaaaaaaaaa
Thicknessaaaaaaaaaa
Login to View More

Abstract

Disclosed is a thin film composite hollow fiber that includes an outer support layer having a thickness of 10 to 10000 μm and a polyamide thin film layer having a thickness of 1 to 10000 nm; and has a transmembrane pressure resistance rate of higher than 15 bar and a pure water permeability rate of higher than 0.8 Lm−2 h−1 bar−1. Also disclosed are methods of preparing the above-described support and composite hollow fiber.

Description

BACKGROUND OF THE INVENTION[0001]Pressure retarded osmosis (PRO) is a membrane-based separation process for harvesting osmotic power, a renewable marine resource.[0002]In a typical PRO process, two solutions of different salinities, i.e., river water and seawater, are separated by a semi-permeable membrane. Osmotic power is generated as a result of a trans-membrane pressure, output of which is used to drive a pressurized stream to a hydro-turbine to generate electricity.[0003]An ideal semi-permeable membrane used in a PRO process has both a high mechanical strength (i.e., capable of withstanding a high transmembrane pressure) and a high pure water permeability (PWP) rate. Yet, a higher mechanical strength typically requires a higher density or a greater thickness of the membrane, which adversely affects the PWP rate.[0004]There is a need to develop a high-performance PRO membrane for use in exploiting osmotic power.SUMMARY OF THE INVENTION[0005]This invention relates to a thin film ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): B29C47/00B01D71/68B01D71/56B01D69/08B29C48/09
CPCB29C47/0023B01D69/088B01D71/68B01D71/56B29C47/0004B29L2031/731B01D2325/24B01D2325/20B29K2081/06B29L2023/00B01D2325/04B01D69/08B01D61/002B01D69/087B01D67/0006B01D67/0009B01D69/02B01D69/10B01D2323/40B29C48/09B29C48/022B01D69/1071B01D69/1251B01D69/107
Inventor ZHANG, SUISUKITPANEENIT, PANUCHUNG, TAI-SHUNGWAN, CHUNFENG
Owner NAT UNIV OF SINGAPORE
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com