Process for producing composite reverse osmosis membrane

A technology of reverse osmosis membrane and manufacturing method, applied in reverse osmosis, semi-permeable membrane separation, chemical instruments and methods, etc., can solve the problems of coating interruption, difficult acid halide concentration, uneven coating of reverse osmosis membrane, etc., and achieve reliable High performance, simplifies cleaning operations, and reduces usage

Active Publication Date: 2007-09-12
NITTO DENKO CORP
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  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, excessive coating must be prevented in the dipping coating method, and composite reverse osmosis membranes can only be manufactured at a relatively low speed of about 3 to 6 m / min.
[0005] 2) It is difficult to stably maintain the concentration of acid halides in the organic solution, and it is difficult to continuously manufacture composite reverse osmosis membranes for a long time
Therefore, even if the precision of the device is very high, it is difficult to uniformly coat a thin layer of several μm to 10 μm, and there is a possibility of uneven coating or coating interruption that will fatally affect the performance of the reverse osmosis membrane.
Therefore, it is substantially difficult to apply the tandem coating method in the manufacture of composite reverse osmosis membranes on an industrial scale.
[0010] As mentioned above, there has not been found a method that can solve the problems of the dipping coating method and can continuously manufacture composite reverse osmosis membranes with high efficiency.

Method used

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  • Process for producing composite reverse osmosis membrane
  • Process for producing composite reverse osmosis membrane
  • Process for producing composite reverse osmosis membrane

Examples

Experimental program
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Effect test

Embodiment 1

[0103] Prepare the aqueous solution a- 1. And organic solution b-1 (organic solvent: IP solvent) containing 0.25% by weight of trimesoyl chloride. Using the apparatus shown in FIG. 4, the porous support was conveyed at a speed of 20 m / min, and the aqueous solution a-1 was coated on the porous support with a thickness of 30 μm by a slot die coater to form an aqueous solution coating layer. Thereafter, when 0.9 m was conveyed, that is, 2.7 seconds after application of the aqueous solution a-1, the aqueous solution coating layer was almost completely removed with a rubber squeegee wiper. Next, it was sent to a slit die coater installed immediately behind the blade wiper, and the organic solution b-1 was applied to a thickness of 50 μm, and was conveyed for about 2 m under room temperature atmosphere while causing interfacial polymerization reaction. Thereafter, it was sent to a drying oven at 120° C., and dried for about 30 seconds to form a polyamide-based skin layer on the por...

Embodiment 2

[0116] Except adopting the device shown in Fig. 5, the coating mechanism of the aqueous solution a-1 is specified as a micro-gravure coating machine, and the composite reverse osmosis membrane is produced in the same way as in Example 1.

[0117] A performance test was carried out on the composite reverse osmosis membrane obtained by the same method as in Example 1, and the salt rejection rate formed by the permeate conductivity was 99.84%, and the permeate flow rate was 1.64m 3 / m 2 ·day.

Embodiment 3

[0119] Prepare the aqueous solution a- 2. And organic solution b-1 (organic solvent: IP solvent) containing 0.25% by weight of trimesoyl chloride. Using the apparatus shown in FIG. 3, the porous support was conveyed at a speed of 20 m / min, and the aqueous solution a-2 was coated on the porous support with a thickness of 40 μm using a slot die coater to form an aqueous solution coating layer. Thereafter, when transporting 0.2 m, that is, 0.6 seconds after application of the aqueous solution a-2, the aqueous solution coating layer was substantially completely removed with an air knife (speed: 100 m / min). In addition, the weight of the support before applying the aqueous solution a-2 and the weight of the support after removing the aqueous solution coating layer with an air knife were measured, and the weight per unit area was 153.9 g / m 2 and 154.8g / m 2 , it was confirmed that the aqueous solution coating layer was substantially completely removed. Next, it is sent to a slot d...

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Abstract

An object of the present invention is to provide an industrially stable process for continuously producing a composite reverse osmosis membrane. The present invention relates to a process for continuously producing a composite reverse osmosis membrane comprising a polyamide skin layer and a porous support for supporting the polyamide skin layer, the method comprising the steps of: A) applying an aqueous solution +- containing a compound having two or more reactive amino groups to form a covering layer of an aqueous solution on the porous support while moving the porous support; B) pemeating the aqueous solution +- in micro pores of the porous support by holding the covering layer of the aqueous solution on the porous support for 0.2 to 15 seconds; C) removing the covering layer of the aqueous solution while holding the aqueous solution +- within the micro pores of the porous support; and D) after C, forming the polyamide skin layer by applying an organic solution containing a polyfunctional acid halide onto the surface of the porous support to make the aqueous solution +- contact with the organic solution for interfacial polymerization.

Description

technical field [0001] The present invention relates to a method for producing composite reverse osmosis in which a polyamide-based skin layer is formed on the surface of a porous support. Specifically, it relates to efficient continuous production of water used in the desalination of seawater or alkaline water, the production of ultrapure water, the concentration of valuables in the pharmaceutical and food industries, and the treatment of industrial effluents such as dyeing effluents and electrodeposition paint effluents. A method for a composite reverse osmosis membrane with excellent permeation performance and salt blocking performance. Background technique [0002] Composite reverse osmosis membrane is widely used in the manufacture of ultrapure water, desalination of alkaline water or seawater, etc. In addition, it also contributes to the sealing of drainage by removing and recovering pollution sources or effective substances contained in pollutants, etc., which are th...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): B01D67/00B01D71/56B01D61/02B01D69/12
Inventor 石塚浩敏高田政胜名仓克守广濑雅彦西山真哉松尾洋
Owner NITTO DENKO CORP
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