Asymmetric hollow fiber loaded graphene oxide separation membrane

Abstract

The utility model relates to an asymmetric hollow fiber loaded graphene oxide separation membrane. The separation membrane sequentially comprises a compact graphene sponge layer, a supporting graphene sponge layer and a woven polymer graphene interpenetrating layer, wherein the woven polymer graphene interpenetrating layer comprises a graphene sponge body which is connected with one surface, deviating from the compact graphene sponge layer, of the supporting graphene sponge layer; the riveting hole is formed in the graphene sponge body in a penetrating manner; the plurality of hollow woven fibers are riveted in the riveting holes along a first direction parallel to the graphene sponge layer. While the structural rigidity and high pressure resistance of the separation membrane are improved, the structural flux loss is avoided, and the advantages of high water production flux and long-term stability of operation flux are maintained. Meanwhile, the hollow woven fibers are arranged in the riveting holes, so that the anti-pollution capability and the backwashing capability of the separation membrane are improved.

Description

Technical Field

[0001] The present application relates to a graphene separation membrane, and in particular to an asymmetric hollow fiber-loaded graphene oxide separation membrane. Background Art

[0002] In the field of water treatment, separation membrane technology is one of the core technologies. At present, most separation membranes on the market adopt homogeneous or symmetrical structural designs. Although these designs show good performance in some applications, they often have obvious deficiencies in structural stiffness, pressure resistance and anti-fouling ability. In particular, during long-term operation, due to the homogeneity of the structure, separation membranes often encounter performance degradation caused by structural deformation, increased pressure loss and accumulation of pollutants. In addition, although traditional separation membranes can try to improve their performance through structural or material improvements, they usually sacrifice membrane flux or increase manufacturing costs. For example, increasing the thickness of the membrane can improve its pressure resistance, but it will also lead to a decrease in filtration flux and affect water treatment efficiency. At the same time, existing separation membranes often cannot meet more stringent application requirements in terms of backwashing and anti-fouling performance, which limits its feasibility in industrial-scale application. Therefore, it is necessary to provide an asymmetric hollow fiber loaded graphene oxide separation membrane with high structural strength, high pressure resistance, high water production flux, long-term stable operating flux, high anti-fouling ability and backwashing effect. Utility Model Content

[0003] The purpose of the present application is to provide an asymmetric hollow fiber loaded graphene oxide separation membrane with high structural strength, high pressure resistance, high water production flux, long-term stable operating flux, high anti-fouling ability and backwashing effect.

[0004] According to one aspect of the present application, an asymmetric hollow fiber supported graphene oxide separation membrane is provided, which comprises in sequence: a dense graphene sponge layer, a supporting graphene sponge layer and a woven polymer graphene interpenetrating layer; wherein,

[0005] The density of the dense graphene sponge layer is recorded as P, and the density of the supporting graphene sponge layer is recorded as T, satisfying the relationship: P>2T; wherein the woven polymer graphene interpenetrating layer includes:

[0006] A graphene sponge body connected to a side of the supporting graphene sponge layer away from the dense graphene sponge layer;

[0007] A riveting hole is formed through the graphene sponge;

[0008] Hollow woven fibers, a plurality of the hollow woven fibers are riveted into the rivet holes along a first direction parallel to the graphene sponge layer.

[0009] More preferably, the thickness of the dense graphene sponge layer is denoted as H1, which satisfies the relationship:

[0010] 20um≤H1≤50um.

[0011] More preferably, the relationship is satisfied:

[0012] 30um≤H1≤40um.

[0013] More preferably, the thickness of the supporting graphene sponge layer is denoted as H2, which satisfies the relationship:

[0014] 40um≤H2≤100um.

[0015] More preferably, the relationship is satisfied:

[0016] 60um≤H2≤80um.

[0017] More preferably, the thickness of the braided polymer graphene interpenetrating layer is denoted as H2, which satisfies the relationship:

[0018] 50um≤H3≤500um.

[0019] More preferably, the relationship is satisfied:

[0020] 100um≤H3≤400um.

[0021] More preferably, P>2.5T.

[0022] More preferably, the dense graphene sponge layer and the supporting graphene sponge layer are graphene oxide layers.

[0023] More preferably, the hollow braided fibers are hollow tubular braided fibers.

[0024] This application has the following beneficial effects:

[0025] By setting a dense graphene sponge layer with a higher density and a supporting graphene sponge layer with a lower density, this asymmetric gradient sponge structure design improves the structural rigidity and high pressure resistance of the separation membrane while having no structural flux loss, maintaining the advantages of high water production flux and long-term stable operating flux. Through the riveted woven polymer graphene interpenetrating layer, the hollow woven fiber is placed in the riveted hole, which improves the anti-fouling ability and backwashing ability of the separation membrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 This is a schematic diagram of the hierarchical structure principle of an asymmetric hollow fiber-loaded graphene oxide separation membrane described in one embodiment of the present application.

[0028] Description of the accompanying drawings: 100, graphene oxide separation membrane; 10, dense graphene sponge layer; 20, supporting graphene sponge layer; 30, woven polymer graphene interpenetrating layer; 31, graphene sponge body; 32, riveting hole; 33, hollow woven fiber; F1, first direction; DETAILED DESCRIPTION

[0029] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are given in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0030] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0032] Please refer to Figure 1 An embodiment of the present application provides an asymmetric hollow fiber loaded graphene oxide separation membrane, which comprises in sequence: a dense graphene sponge layer, a supporting graphene sponge layer and a woven polymer graphene interpenetrating layer.

[0033] Among them, graphene refers to graphene oxide, which is a new material with carbon atoms connected by sp2 hybridization tightly stacked into a single-layer two-dimensional honeycomb lattice structure. Graphene has excellent optical, electrical and mechanical properties, and has important application prospects in materials science, micro-nano processing, energy, biomedicine and drug delivery, and is considered to be a revolutionary material in the future. However, since pure graphene is not easy to disperse evenly in other media, graphene oxide with a layered structure extremely similar to graphene is favored by researchers. Graphene oxide not only has a similar structure to graphene, but also has a large number of active groups such as hydroxyl, epoxy, and carboxyl groups on its surface. The large specific surface area and layered structure of graphene oxide determine that the ion exchange capacity of graphene oxide is large. The oxygen-containing groups rich in the surface of the layered structure determine that graphene oxide can be evenly dispersed in water. Hydrophilic molecules and polymers can be inserted into the interlayer of graphene oxide through interlayer hydrogen bonds, ionic bonds and covalent bonds to form interlayer compounds, which makes it have great potential and application prospects in the field of separation materials.

[0034] Among them, the dense graphene sponge layer is mainly responsible for filtering and blocking unwanted substances. Graphene sponge has a highly porous structure, which gives it a high surface area and unique adsorption properties. In the separation membrane, the dense graphene sponge layer is designed more tightly than the supporting graphene sponge layer, which helps to enhance its ability to block fine particles or molecules while maintaining a high water flux. This layer has strong mechanical strength and chemical stability, and can maintain its performance under various environmental conditions.

[0035] The supporting graphene sponge layer is located under the dense graphene sponge layer, and its main function is to provide structural support and protect the dense layer from mechanical damage. Compared with the dense layer, this layer of graphene sponge has a lower density and higher porosity, which helps to reduce the resistance of the overall membrane, allowing water and other media that need to be filtered to pass more easily. At the same time, the lower density also helps to improve the overall flexibility and pressure resistance of the membrane.

[0036] The woven polymer graphene interpenetrating layer is constructed by interpenetrating woven polymer and graphene fibers. The woven structure of the polymer provides additional mechanical strength, while the addition of graphene enhances chemical stability and anti-fouling ability. This structural design not only improves the overall durability and anti-fouling ability of the separation membrane, but also makes the membrane more effective during the backwashing process, capable of removing accumulated pollutants, thereby extending the service life of the membrane.

[0037] The density of the dense graphene sponge layer is recorded as P, and the density of the supporting graphene sponge layer is recorded as T, satisfying the relationship: P>2T.

[0038] More preferably, P>2.5T.

[0039] Wherein, the braided polymer graphene interpenetrating layer comprises: a graphene sponge, riveted holes and hollow braided fibers.

[0040] The graphene sponge body is connected to a side of the supporting graphene sponge layer away from the dense graphene sponge layer. A rivet hole is formed through the graphene sponge body. A plurality of hollow woven fibers are riveted in the rivet hole along a first direction parallel to the graphene sponge layer.

[0041] The graphene sponge acts as the basic support structure in the woven polymer graphene interpenetrating layer. Its high porosity and unique surface properties give it excellent adsorption characteristics and structural strength. In the separation membrane, this layer of graphene sponge is connected to the outside of the supporting graphene sponge layer, that is, the side away from the dense graphene sponge layer. This layout contributes to the overall mechanical strength and pressure resistance of the separation membrane without interfering with the filtration function of the dense layer.

[0042] The rivet holes formed on the graphene sponge are used to install the hollow woven fibers. The rivet holes are evenly distributed and penetrate the entire graphene sponge layer to fix the woven fibers.

[0043] The hollow woven fibers are made of highly durable materials, such as polymers or reinforced composites, with good mechanical strength and chemical stability. They are riveted into the riveting holes of the graphene sponge, which not only increases the overall structural strength of the membrane, but also helps to maintain the position of the fibers and the integrity of the overall structure during backwashing.

[0044] More preferably, the thickness of the dense graphene sponge layer is denoted as H1, which satisfies the relationship: 20um≤H1≤50um.

[0045] More preferably, the relationship is satisfied: 30um≤H1≤40um.

[0046] More preferably, the thickness of the supporting graphene sponge layer is denoted as H2, which satisfies the relationship: 40um≤H2≤100um.

[0047] More preferably, the relationship is satisfied: 60um≤H2≤80um.

[0048] More preferably, the thickness of the braided polymer graphene interpenetrating layer is denoted as H2, which satisfies the relationship: 50um≤H3≤500um.

[0049] More preferably, the relationship is satisfied: 100um≤H3≤400um.

[0050] More preferably, the dense graphene sponge layer and the supporting graphene sponge layer are graphene oxide layers.

[0051] More preferably, the hollow braided fibers are hollow tubular braided fibers.

[0052] This specific embodiment also provides a preparation process for realizing the separation membrane. The preparation of the sponge can be carried out by mixing graphene powder and surfactant to form a uniform slurry, and removing the solvent by freeze drying to form a porous graphene sponge. The difficulty lies in the preparation of the riveted woven polymer graphene interpenetrating layer. Hollow tubular woven fibers can be formed by polyamide, polyester or other suitable high-performance polymers, and the woven fibers are cut and arranged. Then, graphene powder and surfactant are mixed around the woven fibers to form a graphene sponge, thereby obtaining a woven polymer graphene interpenetrating layer with a riveted structure.

[0053] Thus, by setting a dense graphene sponge layer with a higher density and a supporting graphene sponge layer with a lower density, the asymmetric gradient sponge structure design improves the structural rigidity and high pressure resistance of the separation membrane, while there is no structural flux loss, maintaining the advantages of high water production flux and long-term stable operation flux. Through the riveted woven polymer graphene interpenetrating layer, the hollow woven fiber is arranged in the riveted hole, which improves the anti-fouling ability and backwashing ability of the separation membrane.

[0054] The above-described embodiments only express several embodiments of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. An asymmetric hollow fiber supported graphene oxide separation membrane, characterized in that: Including in order: A dense graphene sponge layer, a supporting graphene sponge layer and a woven polymer graphene interpenetrating layer; wherein, The density of the dense graphene sponge layer is recorded as P, and the density of the supporting graphene sponge layer is recorded as T, satisfying the relationship: P>2T; wherein the woven polymer graphene interpenetrating layer includes: A graphene sponge body connected to a side of the supporting graphene sponge layer away from the dense graphene sponge layer; A riveting hole is formed through the graphene sponge; Hollow woven fibers, a plurality of the hollow woven fibers are riveted into the rivet holes along a first direction parallel to the graphene sponge layer.

2. The asymmetric hollow fiber supported graphene oxide separation membrane according to claim 1, characterized in that: The thickness of the dense graphene sponge layer is recorded as H1, which satisfies the relationship: 20um≤H1≤50um.

3. The asymmetric hollow fiber supported graphene oxide separation membrane according to claim 2, characterized in that: Satisfies the relationship: 30um≤H1≤40um.

4. The asymmetric hollow fiber supported graphene oxide separation membrane according to claim 1, characterized in that: The thickness of the supporting graphene sponge layer is recorded as H2, which satisfies the relationship: 40um≤H2≤100um.

5. The asymmetric hollow fiber supported graphene oxide separation membrane according to claim 4, characterized in that: Satisfies the relationship: 60um≤H2≤80um.

6. The asymmetric hollow fiber supported graphene oxide separation membrane according to claim 1, characterized in that: The thickness of the woven polymer graphene interpenetrating layer is recorded as H2, which satisfies the relationship: 50um≤H3≤500um.

7. The asymmetric hollow fiber supported graphene oxide separation membrane according to claim 6, characterized in that: Satisfies the relationship: 100um≤H3≤400um.

8. The asymmetric hollow fiber supported graphene oxide separation membrane according to claim 1, characterized in that: Satisfies the relationship: P>2.5T.

9. The asymmetric hollow fiber supported graphene oxide separation membrane according to claim 1, characterized in that: The dense graphene sponge layer and the supporting graphene sponge layer are graphene oxide layers.

10. The asymmetric hollow fiber supported graphene oxide separation membrane according to claim 1, characterized in that: Hollow braided fibers are braided fibers that are hollow and tubular.

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