Preparation and application of efficient separation membrane material

Abstract

The invention discloses preparation and application of an efficient separation membrane material, and belongs to the technical field of membrane separation materials. Through the unique two-dimensional layered structure and rich oxygen-containing functional groups of the graphene oxide in the separation membrane, the separation membrane can show excellent size screening effect and charge effect in the separation process, so that efficient separation of a target substance is realized, the separation efficiency is improved, and the separation cost is reduced. Oxygen-containing functional groups on the surface of the graphene oxide endow the graphene oxide with good hydrophilicity, so that water molecules can more easily pass through a membrane layer, meanwhile, adsorption and deposition of pollutants on the surface of the separation membrane are reduced, the service life of the membrane is prolonged, and the graphene oxide separation membrane has good hydrophilicity and pollution resistance; secondly, the separation membrane can still keep stable separation performance in severe environments such as high pressure and high temperature.

Description

Technical Field

[0001] The invention belongs to the technical field of membrane separation materials, and in particular relates to the preparation and application of a high-efficiency separation membrane material. Background Art

[0002] With the increasing severity of global water shortage and environmental pollution problems, efficient, energy-saving and environmentally friendly separation technology has become a research hotspot. Traditional separation membrane materials have many shortcomings in separation efficiency, durability and cost, and it is difficult to meet the needs of modern industry for high-quality separation technology. Therefore, a preparation and application of efficient separation membrane materials is proposed. Summary of the invention

[0003] The purpose of the present invention is to provide a method for preparing a high-efficiency separation membrane material and its application, so as to solve the problems raised in the above-mentioned background technology.

[0004] To achieve the above object, the present invention provides the following technical solution: a preparation method of a high-efficiency separation membrane material and its application, the preparation method comprising the following steps:

[0005] S1, dispersing graphene oxide powder in a solvent, and forming a uniform stone mixed dispersion by ultrasonic treatment;

[0006] S2. Select a suitable substrate material, such as polysulfone, prepare a substrate membrane by a phase inversion method or a coating method, and perform necessary cleaning and drying processes;

[0007] S3, immersing the base film in the graphene oxide dispersion obtained in step S1, forming a graphene oxide layer on the surface of the base film material through an appropriate film-forming process, and cross-linking the base film with the graphene oxide layer deposited thereon to enhance the bonding force between the graphene oxide layer and the base film, and improve the mechanical strength and stability of the film;

[0008] S4, taking out the prepared separation membrane and washing it to remove unreacted raw materials and impurities, drying it, usually drying it naturally at room temperature or drying it in a low-temperature oven to remove residual solvent, and heat-treating the separation membrane prepared in step S3 to firmly combine the metal oxide catalyst with high catalytic activity with the base membrane to obtain a high-efficiency catalytic separation membrane;

[0009] S5. To further improve the performance of the separation membrane, the surface of the separation membrane can be modified after the heat treatment. The dried sample is placed in a furnace, heated to a set temperature under the protection of an inert gas, and then naturally cooled to room temperature after a certain period of time to enhance its selectivity, permeability or stability.

[0010] As a further preferred embodiment of the present technical solution: the solvent of the mixed dispersion is deionized water or an organic solvent, and the ultrasonic treatment time ranges from several hours to dozens of hours to ensure that the graphene oxide powder is fully dispersed;

[0011] As a further preferred embodiment of the present technical solution: the graphene oxide layer deposition method includes vacuum filtration, dip coating, and spin coating, and the heat treatment temperature and time in S4 are set according to the stability of the mixed ligand and the performance requirements of the film;

[0012] As a further preferred embodiment of the present technical solution: the cross-linking treatment in S3 adopts a chemical cross-linking method, and the cross-linking agent can be a compound containing multiple functional groups such as glutaraldehyde and diethylenetriamine;

[0013] As a further preferred embodiment of the present technical solution: the inert gas in S5 is nitrogen, the temperature in S5 is set to 200° C., and the time in S5 is set to 2 hours.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention uses the unique two-dimensional layered structure and rich oxygen-containing functional groups of graphene oxide in the separation membrane to enable the separation membrane to exhibit excellent size screening effect and charge effect during the separation process, thereby achieving efficient separation of target substances and improving separation efficiency. In addition, the oxygen-containing functional groups on the surface of graphene oxide give it good hydrophilicity, allowing water molecules to pass through the membrane layer more easily, while reducing the adsorption and deposition of pollutants on the surface of the separation membrane, extending the service life of the membrane, and having good hydrophilicity and anti-pollution properties. Secondly, the separation membrane can still maintain stable separation performance under harsh environments such as high pressure and high temperature. DETAILED DESCRIPTION

[0015] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0016] Example

[0017] The present invention provides a technical solution: a preparation method of a high-efficiency separation membrane material and its application, characterized in that the preparation method comprises the following steps:

[0018] S1, dispersing graphene oxide powder in a solvent, and forming a uniform mixed dispersion by ultrasonic treatment;

[0019] S2. Select a suitable substrate material, such as polysulfone, prepare a substrate membrane by a phase inversion method or a coating method, and perform necessary cleaning and drying processes;

[0020] S3, immersing the base film in the mixed dispersion obtained in step S1, forming a graphene oxide layer on the surface of the base film material through an appropriate film-forming process, and cross-linking the base film with the graphene oxide layer deposited thereon to enhance the bonding force between the graphene oxide layer and the base film, and improve the mechanical strength and stability of the film;

[0021] S4, taking out the prepared separation membrane and washing it to remove unreacted raw materials and impurities, drying it, usually drying it naturally at room temperature or drying it in a low-temperature oven to remove residual solvent, and heat-treating the separation membrane prepared in step S3 to firmly combine the metal oxide catalyst with high catalytic activity with the base membrane to obtain a high-efficiency catalytic separation membrane;

[0022] S5. To further improve the performance of the separation membrane, the surface of the separation membrane can be modified after the heat treatment. The dried sample is placed in a furnace, heated to a set temperature under the protection of an inert gas, and then naturally cooled to room temperature after a certain period of time to enhance its selectivity, permeability or stability.

[0023] In this embodiment, specifically: the solvent of the mixed dispersion is deionized water or an organic solvent, and the ultrasonic treatment time ranges from several hours to dozens of hours to ensure that the graphene oxide powder is fully dispersed;

[0024] In this embodiment, specifically: the graphene oxide layer deposition method includes vacuum filtration, dip coating, and spin coating, and the heat treatment temperature and time in S4 are set according to the stability of the mixed ligand and the performance requirements of the film;

[0025] In this embodiment, specifically: the cross-linking treatment in S3 adopts a chemical cross-linking method, and the cross-linking agent can be a compound containing multiple functional groups such as glutaraldehyde and diethylenetriamine;

[0026] In this embodiment, specifically: the inert gas in S5 is nitrogen, the temperature in S5 is set to 200° C., and the time in S5 is set to 2 hours.

[0027] Working principle or structural principle: First, the mixture to be separated is transported to one side of the membrane by a pump or other means. The components in the mixture contact the membrane surface and start the separation process according to the selective permeability of the membrane. The membrane material selectively allows the components in the mixture to pass through the membrane pores to enter the other side to form a permeate according to factors such as pore size and material properties, while other components are retained by the membrane to form a retentate. With the continuous input of the mixture and the continuation of the separation process, the permeate and the retentate are collected at different outlets respectively. The permeate contains the components that pass through the membrane pores, while the retentate contains the components retained by the membrane, thereby achieving effective separation of the mixture. The permeate and the retentate are further processed or utilized as needed, and the membrane is cleaned and maintained to maintain its separation performance and extend its service life.

[0028] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Preparation and application of a high-efficiency separation membrane material, It is characterized in that The preparation method comprises the following steps: S1, dispersing graphene oxide powder in a solvent, and forming a uniform mixed dispersion by ultrasonic treatment; S2. Select a suitable substrate material, such as polysulfone, prepare a substrate membrane by a phase inversion method or a coating method, and perform necessary cleaning and drying processes; S3, immersing the base film in the mixed dispersion obtained in step S1, forming a graphene oxide layer on the surface of the base film material through an appropriate film-forming process, and cross-linking the base film with the graphene oxide layer deposited thereon to enhance the bonding force between the graphene oxide layer and the base film, and improve the mechanical strength and stability of the film; S4, taking out the prepared separation membrane and washing it to remove unreacted raw materials and impurities, drying it, usually drying it naturally at room temperature or drying it in a low-temperature oven to remove residual solvent, and heat-treating the separation membrane prepared in step S3 to firmly combine the metal oxide catalyst with high catalytic activity with the base membrane to obtain a high-efficiency catalytic separation membrane; S5. To further improve the performance of the separation membrane, the surface of the separation membrane can be modified after heat treatment. The dried sample is placed in a furnace, heated to a set temperature under the protection of an inert gas, kept warm for a certain period of time, and then naturally cooled to room temperature to enhance its selectivity, permeability or stability.

2. The preparation and application of a high-efficiency separation membrane material according to claim 1, Features: The solvent of the mixed dispersion is deionized water or an organic solvent, and the ultrasonic treatment time ranges from several hours to dozens of hours to ensure that the graphene oxide powder is fully dispersed.

3. The preparation and application of a high-efficiency separation membrane material according to claim 1, Features: The graphene oxide layer deposition method includes vacuum filtration, dip coating, and spin coating. The heat treatment temperature and time in S4 are set according to the stability of the mixed ligand and the performance requirements of the film.

4. The preparation and application of a high-efficiency separation membrane material according to claim 1, Features: The cross-linking treatment in S3 adopts a chemical cross-linking method, and the cross-linking agent can be a compound containing multiple functional groups such as glutaraldehyde and diethylenetriamine.

5. The preparation and application of a high-efficiency separation membrane material according to claim 1, Features: The inert gas in S5 is nitrogen, the temperature in S5 is set to 200° C., and the time in S5 is set to 2 hours.