Composite microporous membranewith symmetric pore structure, and preparation method thereof

A technology of microporous membrane and pore structure, applied in the field of microporous membrane, can solve the problems of bulky membrane elements, complicated preparation process, high maintenance cost, etc., and achieve the effect of simple preparation process, broad market prospect and reduced maintenance cost

Active Publication Date: 2020-12-25
JIANGSU HORIZON NEW ENERGY TECH CO LTD
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, the reverse osmosis and nanofiltration membranes used for water treatment basically use three-layer composite membranes of non-woven fabrics, polysulfone membranes and polyamide desalination layers. The thickness of this membrane is basically about 110nm, and the preparation process is complicated. Imported, the prepared membrane elements are bulky, low in efficiency and high in maintenance costs in practical applications

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
  • Composite microporous membranewith symmetric pore structure, and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0057] The preparation method of polyethylene wet-process diaphragm / polyethylene wet-process diaphragm composite microporous membrane is as follows:

[0058] S1. Preparation of mechanical support layer: Preparation of polyethylene wet-process separator

[0059] A. Blending and extrusion: mixing polyethylene resin and processing aids and introducing them into a twin-screw extruder to melt and extrude to obtain a melt;

[0060] B. Cast sheet cooling: cooling and crystallizing the extruded melt to obtain a gel sheet;

[0061] C. Stretching: Stretch the gel sheet 4 times longitudinally and then 4 times transversely at a temperature of 70°C to obtain a stretched film;

[0062] D. Extraction: immerse the stretched film in a dichloromethane solution for extraction, so that the processing aid therein is separated from the film body to obtain a mechanical support layer;

[0063] S2. Preparation of filter layer: preparation of polyethylene wet-process membrane

[0064] A. Blending an...

Embodiment 2

[0072] The preparation method of polyethylene wet-process diaphragm / polyethylene wet-process diaphragm composite microporous membrane is as follows:

[0073] S1. Preparation of mechanical support layer: Preparation of polyethylene wet-process separator

[0074] A. Blending and extrusion: mixing polyethylene resin and processing aids and introducing them into a twin-screw extruder to melt and extrude to obtain a melt;

[0075] B. Cast sheet cooling: cooling and crystallizing the extruded melt to obtain a gel sheet;

[0076] C. Stretching: Stretch the gel sheet 4 times longitudinally and then 4 times transversely at a temperature of 85°C to obtain a stretched film;

[0077] D. Extraction: immerse the stretched film in a dichloromethane solution for extraction, so that the processing aid therein is separated from the film body to obtain a mechanical support layer;

[0078] S2. Preparation of filter layer: preparation of polyethylene wet-process membrane

[0079] A. Blending an...

Embodiment 3

[0088] The preparation method of polyethylene wet-process diaphragm / polyethylene wet-process diaphragm composite microporous membrane is as follows:

[0089] S1. Preparation of mechanical support layer: Preparation of polyethylene wet-process separator

[0090] A. Blending and extrusion: mixing polyethylene resin and processing aids and introducing them into a twin-screw extruder to melt and extrude to obtain a melt;

[0091] B. Cast sheet cooling: cooling and crystallizing the extruded melt to obtain a gel sheet;

[0092] C. Stretching: Stretch the gel sheet 4 times longitudinally and then 4 times transversely at a temperature of 110°C to obtain a stretched film;

[0093] D. Extraction: immerse the stretched film in a dichloromethane solution for extraction, so that the processing aid therein is separated from the film body to obtain a mechanical support layer;

[0094] S2. Preparation of filter layer: preparation of polyethylene wet-process membrane

[0095] A. Blending a...

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
Apertureaaaaaaaaaa
Thicknessaaaaaaaaaa
Thicknessaaaaaaaaaa
Login to View More

Abstract

The invention discloses a composite microporous membrane with an asymmetric pore structure, and a preparation method thereof . The preparation method comprises the following steps: preparing a mechanical support layer and a filter layer with microporous structures by a unidirectional stretching or bidirectional stretching method, and controlling the average pore size and the film thickness of themechanical support layer and the filter layer by controlling the stretching multiple and the hot-pressing temperature. The mechanical support layer and the filter layer are large in pore size and porosity difference, and the mechanical support layer and one or more filter layers are compounded through high-temperature hot pressing, so the prepared composite microporous membrane has an asymmetric pore structure, the pore size of the composite microporous membrane is smaller, reverse osmosis / nanofiltration operation can be performed on a water sample with higher packing density, and the water treatment effect is greatly improved.

Description

technical field [0001] The invention relates to the technical field of microporous membranes, in particular to a composite microporous membrane with an asymmetric pore structure and a preparation method thereof. Background technique [0002] Membrane separation technology is an emerging high-end treatment technology, which can not only separate and purify various components, but also does not produce any environmental pollution and other negative effects in the whole process; in today's increasingly scarce water resources, people The demand for fresh water is increasing, but the earth's fresh water resources are very limited, while the amount of other water, such as seawater, domestic wastewater, industrial wastewater, etc. is very large, so extracting usable fresh water from these waters has become a global consensus. At present, the reverse osmosis and nanofiltration membranes used for water treatment basically use three-layer composite membranes of non-woven fabrics, pol...

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): B01D67/00B01D69/10B01D71/36
CPCB01D71/36B01D69/10B01D67/0002B01D2325/022Y02A20/131
Inventor刘涛涛翁星星贾培梁沈亚定
OwnerJIANGSU HORIZON NEW ENERGY TECH CO LTD