阅读说明：本技术 一种管式膜用复合材料及其制备方法和应用 (Composite material for tubular membrane and preparation method and application thereof ) 是由 戴云帆 杨媛 樊少斌 谢长血 于 2021-07-23 设计创作，主要内容包括：本发明涉及水处理技术领域,具体公开了一种管式膜用复合材料及其制备方法和应用,所述管式膜用复合材料是基于聚偏氟乙烯树脂以及聚醚砜作为主体材料,并通过合理添加改性锂辉石与改性碳酸钙等粉料进行制备获得,可以在保证超滤效果的同时提高进水浊度,而且具有良好的抗拉强度,适用于管式膜产品的制备,解决了现有管式膜用复合材料大多存在进水浊度不高的问题,不适应用于高浊度的恶劣运行状况。而提供的制备方法简单,制备的管式膜用复合材料与传统的膜材料相比,外压可耐受不小于1000NTU的进水浊度,适用于高浊度的恶劣运行状况,应用前景广阔。(The invention relates to the technical field of water treatment, and particularly discloses a composite material for a tubular membrane, and a preparation method and application thereof. Compared with the traditional membrane material, the prepared composite material for the tubular membrane can resist the inlet water turbidity of not less than 1000NTU under external pressure, is suitable for the severe operation condition with high turbidity, and has wide application prospect.)

1. The composite material for the tubular membrane is characterized by comprising the following raw materials in parts by weight: 80-102 parts of main material, 12-22 parts of powder and 68-92 parts of diluent; wherein the main body material is selected from one or more of polyvinylidene fluoride resin and polyether sulfone; the powder is prepared by mixing modified spodumene and modified calcium carbonate according to the mass ratio of 5-10: 3.

2. The composite material for a tubular membrane according to claim 1, wherein the modified calcium carbonate is obtained by mixing and modifying calcium carbonate nano powder as a raw material by adding iodopropynyl butylcarbamate, aminomethyl propanol, ethanol, and a coupling agent.

3. The composite material for a tubular membrane according to claim 2, characterized by comprising, in the raw material of the modified calcium carbonate, in parts by weight: 40-60 parts of calcium carbonate nano powder, 1-3 parts of iodopropynyl alcohol butyl carbamate, 2-7 parts of aminomethyl propanol, 5-8 parts of ethanol and 0.1-1 part of coupling agent.

4. The composite material for tubular membranes as claimed in claim 1, wherein the modified spodumene powder is prepared by using spodumene powder pulverized to micron order as raw material, adding water, ultrasonically dispersing to prepare slurry, then, after vacuumizing, dropping a modifier, reacting at 75 ℃, washing and drying after reaction to obtain the modified spodumene powder; wherein the modifier is prepared by mixing glycerol, trichlorosilane, hydrogen chloride and butyl titanate according to the mass ratio of 16:5:1: 3.

5. The composite material for tubular membranes as claimed in claim 4, wherein the modified spodumene powder comprises the following raw materials in parts by weight: 8-16 parts of spodumene powder and 1-5 parts of modifier.

6. The composite material for a tubular membrane according to claim 1, wherein a mass ratio of the polyvinylidene fluoride resin to the polyether sulfone in the host material is 5-10: 1.

7. The composite material for tubular membranes according to claim 1, wherein the raw materials of the composite material for tubular membranes comprise, in parts by weight: 90 parts of main material, 18 parts of powder and 77 parts of diluent.

8. A process for the preparation of a composite material for tubular membranes according to any one of claims 1 to 7, comprising the steps of:

1) uniformly mixing modified spodumene and modified calcium carbonate, adding a main material and a diluent according to a proportion, and mixing at 70-80 ℃ to obtain a uniform material to obtain a mixture;

2) and mixing the mixture at the mixing temperature of 200 ℃ and 300 ℃ to obtain the composite material for the tubular membrane.

9. The method for producing a composite material for a tubular film according to claim 8, further comprising: after mixing, extruding, drawing, forming and cooling to obtain the composite material for the tubular membrane; wherein, the drawing forming is carried out in a nitrogen environment and then is cooled in the nitrogen environment.

10. Use of a composite material for tubular membranes according to any one of claims 1 to 7 in desalination of sea water and treatment of sewage.

Technical Field

The invention relates to the technical field of water treatment, in particular to a composite material for a tubular membrane and a preparation method and application thereof.

Background

Water resources play an important role in human survival. However, as human life progresses, various types of waste water are generated, and water treatment is required to meet the water quality requirement of finished water (domestic water, process water or waste water to be discharged).

At present, the tubular membrane is used as a common filter membrane product, has wide application prospect in the field of water treatment, and has important significance for environmental protection and ecological balance maintenance. Since the tubular membrane is a cylindrical or cylinder-like membrane cast from a support based on a composite material (membrane material) for tubular membrane, improvement of water quality can be achieved by cross-flow filtration or cross-flow filtration.

Generally, most of the existing membrane materials are materials such as polyether sulfone (PES), polyvinylidene fluoride (PVDF), Polystyrene (PS), Polyamide (PA), and the like, and particularly, polyvinylidene fluoride can occupy a large market in the fields of seawater desalination, preparation of high-quality drinking water, reuse of sewage treatment recycled water, and the like.

However, the existing composite material (membrane material) for tubular membrane has certain defects when being used for treating high-suspension systems such as fermentation liquor, activated sludge and the like, can generally endure the inlet water turbidity of about 300NTU (nephelometric turbidity unit, NTU for short) under external pressure, and is not suitable for severe operating conditions with high turbidity.

Disclosure of Invention

An object of an embodiment of the present invention is to provide a composite material for a tubular membrane, so as to solve the problem that most of the existing composite materials for a tubular membrane proposed in the background art have low inlet water turbidity and are not suitable for severe operating conditions with high turbidity.

In order to achieve the above purpose, the embodiments of the present invention provide the following technical solutions:

a composite material for a tubular membrane, in particular to a special material for a reverse osmosis membrane, which is prepared by taking polyvinylidene fluoride resin and polyether sulfone as main materials and reasonably adding other materials; the composite material for the tubular membrane comprises the following raw materials in parts by weight: 80-102 parts of main material, 12-22 parts of powder and 68-92 parts of diluent. The powder is prepared by mixing modified spodumene and modified calcium carbonate according to the mass ratio of 5-10: 3.

As a further scheme of the invention: the modified calcium carbonate is prepared by adding iodopropynyl alcohol butyl carbamate, aminomethyl propanol, ethanol and a coupling agent into calcium carbonate nano powder serving as a raw material for mixing and modifying.

As a further scheme of the invention: the modified spodumene powder is prepared by taking spodumene powder crushed to micron level as a raw material, adding water, ultrasonically dispersing to prepare slurry, then, dripping a modifier after vacuumizing, reacting at 75 ℃, washing and drying after reaction to obtain the modified spodumene powder; wherein the modifier is prepared by mixing glycerol, trichlorosilane, hydrogen chloride and butyl titanate according to the mass ratio of 16:5:1: 3.

Another object of an embodiment of the present invention is to provide a method for preparing a composite material for a tubular membrane, the method comprising the steps of:

1) at normal temperature, uniformly mixing modified spodumene and modified calcium carbonate, adding a main material (selected from one or more of polyvinylidene fluoride resin and polyether sulfone, preferably the polyvinylidene fluoride resin and the polyether sulfone together) and a diluent in proportion, and mixing at 70-80 ℃ to obtain a uniform material to obtain a mixture;

2) and mixing the mixture at the mixing temperature of 200 ℃ and 300 ℃ to obtain the composite material for the tubular membrane.

Compared with the prior art, the invention has the beneficial effects that:

the composite material for the tubular membrane provided by the embodiment of the invention is a special material for the reverse osmosis membrane, which is prepared by reasonably adding other materials based on polyvinylidene fluoride resin and polyether sulfone as main materials, can ensure the ultrafiltration effect and simultaneously improve the water inlet turbidity by matching with the use of modified spodumene and modified calcium carbonate, has good tensile strength, is suitable for preparing tubular membrane products, solves the problem that most of the existing composite materials for the tubular membrane have low water inlet turbidity, and is not suitable for high-turbidity severe operation conditions. Compared with the traditional membrane material, the prepared composite material for the tubular membrane has the advantages that the external pressure can tolerate the water inlet turbidity of not less than 1000NTU, has good tensile strength, is suitable for severe operation conditions with high turbidity and has wide application prospect.

Drawings

Fig. 1 is a graph showing the result of detecting the turbidity of inlet water of the composite material for a tubular membrane according to an embodiment of the present invention.

Fig. 2 is a graph showing the result of testing the tensile strength of the composite material for a tubular film according to an embodiment of the present invention.

Detailed Description

The invention is described in further detail below with reference to the figures and specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the invention. All falling within the scope of the present invention.

Various modifications to the precise description of the invention will be readily apparent to those skilled in the art from the information contained herein without departing from the spirit and scope of the appended claims. It is to be understood that the scope of the invention is not limited to the procedures, properties, or components defined, as these embodiments, as well as others described, are intended to be merely illustrative of particular aspects of the invention. Indeed, various modifications of the embodiments of the invention which are obvious to those skilled in the art or related fields are intended to be covered by the scope of the appended claims.

The composite material for the tubular membrane provided by the embodiment of the invention is a special material for a reverse osmosis membrane, which is prepared by reasonably adding other materials based on polyvinylidene fluoride resin and polyether sulfone as main materials, and specifically comprises the following raw materials in parts by weight: 80-102 parts of main material, 12-22 parts of powder and 68-92 parts of diluent; wherein the main body material is selected from one or more of polyvinylidene fluoride resin and polyether sulfone; the powder is prepared by mixing modified spodumene and modified calcium carbonate according to the mass ratio of 5-10:3, and is usually ground into nano-scale before the powder is used.

Preferably, the powder material is prepared by mixing modified spodumene and modified calcium carbonate according to the mass ratio of 8: 3.

In another preferred embodiment of the present invention, the modified calcium carbonate is obtained by adding iodopropynyl alcohol butyl carbamate, aminomethyl propanol, ethanol and a coupling agent to calcium carbonate nano powder as a raw material and mixing and modifying the mixture.

As another preferred embodiment of the present invention, the raw materials of the modified calcium carbonate comprise, by weight: 40-60 parts of calcium carbonate nano powder, 1-3 parts of iodopropynyl alcohol butyl carbamate, 2-7 parts of aminomethyl propanol, 5-8 parts of ethanol and 0.1-1 part of coupling agent.

Preferably, the modified calcium carbonate is prepared by adding 2.4 parts of iodopropynyl butylcarbamate, 3.6 parts of aminomethyl propanol, 7 parts of ethanol and 0.5 part of coupling agent into 50 parts of calcium carbonate nano powder, mixing by using a mixer, and performing ultrasonic oscillation under a vacuum condition to complete modification.

The coupling agent is formed by mixing dimethyl dioxysilane and vinyl triethoxysilane in equal mass ratio.

As another preferred embodiment of the present invention, the modified spodumene powder is prepared by taking spodumene powder crushed to micron level as a raw material, adding water, ultrasonically dispersing to prepare slurry, then, after vacuumizing, dropping a modifier, reacting at 75 ℃, washing and drying after reaction to obtain the modified spodumene powder; wherein the modifier is prepared by mixing glycerol, trichlorosilane, hydrogen chloride and butyl titanate according to the mass ratio of 16:5:1: 3.

Generally, spodumene powder is pulverized to the micron level because too large a particle size is not favorable for modifying the modifier, while too small a particle size to the nanometer level causes agglomeration problem and modification is not favorable, and thus modification operation must be performed at the micron level.

As another preferred embodiment of the present invention, the modified spodumene powder comprises the following raw materials in parts by weight: 8-16 parts of spodumene powder and 1-5 parts of modifier.

Preferably, the modified spodumene powder is prepared by adding 12 parts of spodumene powder ball-milled to micron order into water, ultrasonically dispersing into slurry (the concentration is 20-60 wt%), vacuumizing, then adding 1-5 parts of modifier consisting of glycerol, trichlorosilane, hydrogen chloride and butyl titanate dropwise, heating to 75 ℃ for reaction for 3 hours, washing, heating for drying, and crushing to powder to obtain the modified spodumene powder.

In the main body material, the mass ratio of the polyvinylidene fluoride resin to the polyether sulfone is 5-10: 1.

As another preferred embodiment of the present invention, the raw materials of the composite material for tubular membranes comprise, in parts by weight: 90 parts of main material, 18 parts of powder and 77 parts of diluent.

Preferably, in the main body material, the mass ratio of the polyvinylidene fluoride resin to the polyether sulfone is 8:1, namely, the polyvinylidene fluoride resin in 90 parts of the main body material is 80 parts, and the polyether sulfone is 10 parts; wherein, adopt polyvinylidene fluoride resin alone, though can also prepare tubular membrane and use combined material for the membrane and be used for preparing tubular membrane product, nevertheless, the ultrafiltration effect that plays is good, but tensile strength is general, adopts polyether sulfone alone, and the effect is worse, consequently, the cooperation of two kinds of polymer polyvinylidene fluoride resin and polyether sulfone is used, confirms the ratio simultaneously, can prepare the combined material for the tubular membrane of excellent performance.

Further, the polyvinylidene fluoride resin has an average molecular weight of 18 ten thousand daltons and a crystallinity of 53%.

Further, the diluent at least comprises 25 parts of polyvinylpyrrolidone, 40 parts of tetrahydrofuran and 12 parts of benzophenone according to parts by weight.

Further, the average molecular weight of the polyvinylpyrrolidone is 1300000, and the water content is less than 4 wt%.

The embodiment of the invention overcomes the problems that the existing composite material for the tubular membrane is generally about 300NTU of inlet water turbidity, is not suitable for high-turbidity severe running conditions and the like, has certain defects, and is used for treating high-suspension systems such as fermentation liquor, activated sludge and the like; the spodumene and the calcium carbonate have good inorganic-organic composite performance by a modification means, the influence on the uniformity of the composite material caused by direct addition is avoided, and the improvement effect of the spodumene and the calcium carbonate is ensured.

The embodiment of the invention also provides a preparation method of the composite material for the tubular membrane, which comprises the following steps:

1) at normal temperature, uniformly mixing modified spodumene and modified calcium carbonate, adding a main material (one or more selected from polyvinylidene fluoride resin and polyether sulfone) and a diluent according to a proportion, and mixing at 70-80 ℃ to obtain a uniform material to obtain a mixture;

2) and mixing the mixture at the mixing temperature of 200 ℃ and 300 ℃ to obtain the composite material for the tubular membrane.

Further, in the method for preparing the composite material for the tubular membrane, the method further comprises the following steps: and extruding and drawing for molding after mixing, wherein the drawing molding is performed in a nitrogen environment, and then the drawing molding is performed in the nitrogen environment, so that the composite material for the tubular membrane is obtained, and can be used as a tubular membrane component.

Further, in the method for preparing the composite material for the tubular membrane, the method further comprises the following steps: and soaking the obtained composite material for the tubular membrane in a soaking solution, taking out and drying. Wherein the soaking solution is an aqueous solution of glycerol and sodium hyaluronate, the volume percentage of the glycerol is 27%, and the volume percentage of the sodium hyaluronate is 3%.

As another preferred embodiment of the present invention, the solvent used in the soaking solution may be selected from deionized water, ultrapure water, distilled water, etc. Preferably, the solvent used in the soaking solution is ultrapure water.

As another preferred embodiment of the present invention, in the method for preparing the composite material for a tubular film, the soaking time is 40 to 60 hours.

Preferably, in the method for preparing the composite material for the tubular membrane, the soaking time is 50 hours.

As another preferred embodiment of the invention, in the preparation method of the composite material for the tubular membrane, ultrapure water is required to be put into the preparation method for rinsing for 5-10min before being taken out and dried after soaking.

The embodiment of the invention also provides application of the composite material for the tubular membrane in seawater desalination and sewage treatment.

As another preferred embodiment of the invention, the device is particularly suitable for treating high-suspension systems such as fermentation liquor, activated sludge and the like during sewage treatment, and the inlet water turbidity is generally more than 1000NTU, so that the device is suitable for severe operating conditions with high turbidity.

The technical effects of the composite material for tubular membranes of the present invention will be further described below by way of specific examples. For a better understanding of the invention, and not as a limitation on the scope thereof, all numbers expressing quantities, percentages, and other numerical values used in this application are to be understood as being modified in all instances by the term "about". Accordingly, unless expressly indicated otherwise, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

Example 1

A preparation method of a composite material for a tubular membrane comprises the following steps:

(1) adding 2.4 parts of iodopropynyl butylcarbamate, 3.6 parts of aminomethyl propanol, 7 parts of ethanol and 0.5 part of coupling agent into 50 parts of calcium carbonate nano powder according to a proportion, mixing by adopting a stirrer, and performing ultrasonic oscillation (ultrasonic power of 30kHz) under a vacuum condition to complete modification to obtain modified calcium carbonate; the coupling agent is formed by mixing dimethyl dioxy silane and vinyl triethoxy silane in equal mass ratio.

(2) Adding 12 parts of spodumene powder ball-milled to micron level into water according to the proportion, ultrasonically dispersing into slurry (the concentration is 30 wt%), vacuumizing, then dropwise adding 3 parts of modifier consisting of glycerol, trichlorosilane, hydrogen chloride and butyl titanate (mixed according to the mass ratio of 16:5:1: 3), heating to 75 ℃ for reaction for 3 hours, washing, heating for drying, and crushing into powder to obtain the modified spodumene powder.

(3) At normal temperature, uniformly mixing modified spodumene and modified calcium carbonate according to the mass ratio of 8:3 to prepare powder, adding 90 parts of main material (80 parts of polyvinylidene fluoride resin and 10 parts of polyether sulfone in 90 parts of main material) and 77 parts of diluent (polyvinylpyrrolidone: tetrahydrofuran: benzophenone: 25: 40: 12) into 18 parts of powder according to the ratio, and mixing the mixture at 75 ℃ to obtain a uniform material.

(4) And mixing the mixture at the mixing temperature of 240 ℃, then extruding and carrying out traction forming, wherein the mixture is in a nitrogen environment during traction forming, and then cooling the mixture in the nitrogen environment to obtain the composite material for the tubular membrane.

Example 2

A preparation method of a composite material for a tubular membrane comprises the following steps:

(1) adding 2.4 parts of iodopropynyl butylcarbamate, 3.6 parts of aminomethyl propanol, 7 parts of ethanol and 0.1 part of coupling agent into 52 parts of calcium carbonate nano powder according to the proportion, mixing by adopting a stirrer, and performing ultrasonic oscillation (ultrasonic power of 30kHz) under a vacuum condition to complete modification to obtain modified calcium carbonate; the coupling agent is formed by mixing dimethyl dioxy silane and vinyl triethoxy silane in equal mass ratio.

(2) 12 parts of spodumene powder ball-milled to micron level is added with water according to the proportion and ultrasonically dispersed into slurry (the concentration is 30 wt%), after vacuumizing, 3 parts of modifier consisting of glycerol, trichlorosilane, hydrogen chloride and butyl titanate (mixed according to the mass ratio of 16:5:0.6: 3) are added dropwise, the mixture is heated to 75 ℃ for reaction for 3 hours, and the mixture is washed, heated, dried and crushed into powder to obtain the modified spodumene powder.

(3) At normal temperature, uniformly mixing modified spodumene and modified calcium carbonate according to the mass ratio of 8:3 to prepare powder, adding 90 parts of main material (80 parts of polyvinylidene fluoride resin and 10 parts of polyether sulfone in 90 parts of main material) and 77 parts of diluent (polyvinylpyrrolidone: tetrahydrofuran: benzophenone: 25: 40: 12) into 18 parts of powder according to the ratio, and mixing to obtain a uniform material at 70 ℃ to obtain a mixture.

(4) And mixing the mixture at the mixing temperature of 200 ℃, then extruding and carrying out traction forming, wherein the mixture is in a nitrogen environment during traction forming, and then cooling the mixture in the nitrogen environment to obtain the composite material for the tubular membrane.

Example 3

Compared with the embodiment 2, the difference is that: the mixing temperature was 300 ℃.

Example 4

A preparation method of a composite material for a tubular membrane comprises the following steps:

(1) adding 1 part of iodopropynyl butylcarbamate, 2 parts of aminomethyl propanol, 5 parts of ethanol and 0.1 part of coupling agent into 40 parts of calcium carbonate nano powder according to a proportion, mixing by adopting a mixer, and performing ultrasonic oscillation (ultrasonic power is 30kHz) under a vacuum condition to complete modification to obtain modified calcium carbonate; the coupling agent is formed by mixing dimethyl dioxy silane and vinyl triethoxy silane in equal mass ratio.

(2) 8 parts of spodumene powder ball-milled to micron level is added with water according to the proportion and ultrasonically dispersed into slurry (the concentration is 40 wt%), after vacuumizing, 1 part of modifier consisting of glycerol, trichlorosilane, hydrogen chloride and butyl titanate (mixed according to the mass ratio of 16:5:1: 3) is added dropwise, the mixture is heated to 75 ℃ for reaction for 3 hours, and the modified spodumene powder is obtained after washing, heating drying and crushing to powder.

(3) At normal temperature, uniformly mixing modified spodumene and modified calcium carbonate according to the mass ratio of 5:3 to prepare powder, adding 80 parts of main material (the main material adopts polyvinylidene fluoride resin and polyether sulfone, and the mass ratio of the polyvinylidene fluoride resin to the polyether sulfone is 5:1) and 68 parts of diluent (polyvinylpyrrolidone: tetrahydrofuran: benzophenone: 25: 40: 12) into 12 parts of powder according to the ratio, and mixing uniformly at 70 ℃ to obtain a mixture.

(4) And mixing the mixture at the mixing temperature of 200 ℃, then extruding and carrying out traction forming, wherein the mixture is in a nitrogen environment during traction forming, and then cooling the mixture in the nitrogen environment to obtain the composite material for the tubular membrane.

Example 5

In this example, the effect of different mixing temperatures on tensile strength properties was investigated by observing the tensile strength properties of the composite materials for tubular films prepared at different mixing temperatures using the controlled variable method to obtain: the mixing temperature is 245 ℃ and the effect is best.

Example 6

A preparation method of a composite material for a tubular membrane comprises the following steps:

(1) adding 3 parts of iodopropynyl butylcarbamate, 7 parts of aminomethyl propanol, 8 parts of ethanol and 1 part of coupling agent into 60 parts of calcium carbonate nano powder according to a proportion, mixing by using a mixer, and performing ultrasonic oscillation (ultrasonic power of 30kHz) under a vacuum condition to complete modification to obtain modified calcium carbonate; the coupling agent is formed by mixing dimethyl dioxy silane and vinyl triethoxy silane in equal mass ratio.

(2) Adding 16 parts of spodumene powder ball-milled to micron level into water according to the proportion, ultrasonically dispersing the powder into slurry (the concentration is 30 wt%), vacuumizing the slurry, then adding 5 parts of modifier consisting of glycerol, trichlorosilane, hydrogen chloride and butyl titanate dropwise (the modifier is prepared by mixing the raw materials according to the mass ratio of 16:5:1: 3), heating the mixture to 75 ℃ for reaction for 3 hours, washing the reaction product, heating and drying the reaction product, and crushing the reaction product into powder to obtain the modified spodumene powder.

(3) At normal temperature, uniformly mixing modified spodumene and modified calcium carbonate according to the mass ratio of 10:3 to prepare powder, adding 102 parts of main material (the main material adopts polyvinylidene fluoride resin and polyether sulfone, and the mass ratio of the polyvinylidene fluoride resin to the polyether sulfone is 10:1) and 92 parts of diluent (polyvinylpyrrolidone: tetrahydrofuran: benzophenone: 25: 40: 12) into 22 parts of powder according to the ratio, and mixing uniformly at 80 ℃ to obtain a mixture.

(4) And mixing the mixture at the mixing temperature of 300 ℃, then extruding and carrying out traction forming, wherein the mixture is in a nitrogen environment during traction forming, and then cooling the mixture in the nitrogen environment to obtain the composite material for the tubular membrane.

Example 7

A preparation method of a composite material for a tubular membrane comprises the following steps:

(1) adding 1 part of iodopropynyl butylcarbamate, 4 parts of aminomethyl propanol, 6 parts of ethanol and 0.2 part of coupling agent into 45 parts of calcium carbonate nano powder according to a proportion, mixing by using a mixer, and performing ultrasonic oscillation (ultrasonic power is 30kHz) under a vacuum condition to complete modification to obtain modified calcium carbonate; the coupling agent is formed by mixing dimethyl dioxy silane and vinyl triethoxy silane in equal mass ratio.

(2) Adding 9 parts of spodumene powder ball-milled to micron-sized according to the proportion, adding water, ultrasonically dispersing into slurry (the concentration is 30 wt%), vacuumizing, then dropwise adding 1 part of modifier consisting of glycerol, trichlorosilane, hydrogen chloride and butyl titanate (mixed according to the mass ratio of 16:5:1: 3), heating to 75 ℃ for reaction for 3 hours, washing, heating, drying, and crushing into powder to obtain the modified spodumene powder.

(3) At normal temperature, uniformly mixing modified spodumene and modified calcium carbonate according to the mass ratio of 6:3 to prepare powder, adding 90 parts of main material (the main material adopts polyvinylidene fluoride resin and polyether sulfone, and the mass ratio of the polyvinylidene fluoride resin to the polyether sulfone is 7:1) and 75 parts of diluent (polyvinylpyrrolidone: tetrahydrofuran: benzophenone: 25: 40: 12) into 15 parts of powder according to the ratio, and mixing uniformly at 76 ℃ to obtain a mixture.

(4) And mixing the mixture at the mixing temperature of 245 ℃, then extruding and carrying out traction forming, wherein the mixture is in a nitrogen environment during traction forming, and then cooling the mixture in the nitrogen environment to obtain the composite material for the tubular membrane.

Example 8

In this example, the composite material for a tubular membrane prepared in example 1 was subjected to a turbidity test for incoming water, and the composite material for a tubular membrane prepared in example 1 was immersed in an immersion liquid for 50 hours, taken out, rinsed in ultrapure water for 6min, and dried. Wherein the soaking solution is an aqueous solution of glycerol and sodium hyaluronate, the volume percentage of the glycerol is 27%, and the volume percentage of the sodium hyaluronate is 3%. Then the obtained sample is used as a tubular membrane to be tested in seawater ultrafiltration in a Huaneng Yuhuan power plant, and the result shows that the external pressure can endure the inlet water turbidity of 1000NTU, and the specific result is shown in figure 1.

In fig. 1, the point represented by the square is the inlet water turbidity, the point represented by the circle is the penetration turbidity, and the operation time is 0-350 hours, so that the inlet water turbidity can reach over 1000NTU, and the device is suitable for severe operation conditions with high turbidity and can treat high suspension systems such as fermentation liquor, activated sludge and the like.

Example 9

A preparation method of a composite material for a tubular membrane comprises the following steps:

(1) adding 3 parts of iodopropynyl butylcarbamate, 5 parts of aminomethyl propanol, 7 parts of ethanol and 0.6 part of coupling agent into 56 parts of calcium carbonate nano powder according to a proportion, mixing by adopting a mixer, and performing ultrasonic oscillation (ultrasonic power is 30kHz) under a vacuum condition to complete modification to obtain modified calcium carbonate; the coupling agent is formed by mixing dimethyl dioxy silane and vinyl triethoxy silane in equal mass ratio.

(2) 12 parts of spodumene powder ball-milled to micron level is added with water according to the proportion and ultrasonically dispersed into slurry (the concentration is 30 wt%), after vacuumizing, 2 parts of modifier consisting of glycerol, trichlorosilane, hydrogen chloride and butyl titanate (mixed according to the mass ratio of 16:5:1: 3) are added dropwise, the mixture is heated to 75 ℃ for reaction for 3 hours, and the modified spodumene powder is obtained after washing, heating drying and crushing to powder.

(3) At normal temperature, modified spodumene and modified calcium carbonate are uniformly mixed according to the mass ratio of 8:3 to prepare powder, 98 parts of main material (the main material adopts polyvinylidene fluoride resin and polyether sulfone, and the mass ratio of the polyvinylidene fluoride resin to the polyether sulfone is 8:1) and 85 parts of diluent (polyvinylpyrrolidone: tetrahydrofuran: benzophenone: 25: 40: 12) are added into 20 parts of powder according to the proportion, and the mixture is uniformly mixed at 76 ℃ to obtain a mixture.

(4) And mixing the mixture at the mixing temperature of 245 ℃, then extruding and carrying out traction forming, wherein the mixture is in a nitrogen environment during traction forming, and then cooling the mixture in the nitrogen environment to obtain the composite material for the tubular membrane.

Example 10

The comparative example was conducted in the same manner as example 1 except that only polyvinylidene fluoride resin was used as the host material as compared with example 1.

Example 11

The same as example 1 except that polyethersulfone alone was used as the host material as compared with example 1.

Example 12

Compared with the embodiment 1, the composite material for the tubular membrane comprises the following raw materials in parts by weight: the procedure of example 1 was repeated except for using 85 parts of the host material, 18 parts of the powder and 75 parts of the diluent.

Comparative example 1

The modified calcium carbonate of example 1 was replaced with a conventional calcium carbonate heavy calcium powder.

Comparative example 2

The modified spodumene powder of example 1 was replaced with conventional spodumene powder.

Comparative example 3

Commercially available polyvinylidene fluoride ultrafiltration membranes.

Performance detection

Tensile strength tests were conducted using the composite materials for tubular membranes prepared in examples 1 to 4 and comparative examples 1 to 3. Specific test results are shown in table 1.

Table 1 table of tensile strength test results

Group of	Tensile strength (N/mm)2)
		Example 1	7.8
Example 2	7.6
		Example 3	7.6
Example 4	7.7
		Example 5	7.6
Example 6	7.6
		Example 7	7.7
Example 9	7.6
		Example 10	7.1
Example 11	7.2
		Example 12	7.6
Comparative example 1	6.8
		Comparative example 2	6.5
Comparative example 3	2.1

As can be seen from the data in Table 1, the composite material for tubular film provided by the embodiment of the invention has good tensile strength, and the maximum tensile strength can reach 7.8N/mm²When the device is used for treating high-turbidity suspension systems such as fermentation liquor, activated sludge and the like, higher pressure can be applied, good inlet water turbidity is ensured, and the device is suitable for severe high-turbidity running conditions.

The data of the comparative example are combined, so that the modified spodumene and the modified calcium carbonate are matched, the ultrafiltration effect is ensured, and the tensile strength is good, so that the preparation method is suitable for preparing tubular membrane products; the spodumene and the calcium carbonate have good inorganic-organic composite performance by a modification means, the influence on the uniformity of the composite material caused by direct addition is avoided, and the improvement effect of the spodumene and the calcium carbonate is ensured.

The tensile strengths of the samples of example 1 and comparative example 3 were compared to obtain a tensile strength test result chart of the composite material for a tubular film shown in fig. 2. Compared with the polyvinylidene fluoride ultrafiltration membrane sold in the market, the product provided by the invention can be used as a membrane bioreactor, can be applied to the fields of seawater desalination, high-quality drinking water preparation, sewage treatment and reclaimed water recycling and the like, and is beneficial to breaking the dilemma that the high-end fields (ultrapure water for electronic industry, electrophoretic paint recovery, pharmacy, enzyme preparations and the like) in the UF/MF market are basically controlled by foreign enterprises at present.

While the preferred embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the scope of the invention.