CN111346526B - Hollow fiber nanofiltration membrane and preparation method thereof - Google Patents
Hollow fiber nanofiltration membrane and preparation method thereof Download PDFInfo
- Publication number
- CN111346526B CN111346526B CN201811562140.2A CN201811562140A CN111346526B CN 111346526 B CN111346526 B CN 111346526B CN 201811562140 A CN201811562140 A CN 201811562140A CN 111346526 B CN111346526 B CN 111346526B
- Authority
- CN
- China
- Prior art keywords
- hollow fiber
- membrane
- nanofiltration membrane
- fiber nanofiltration
- base
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/72—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, not provided for in a single one of the groups B01D71/46 - B01D71/70 and B01D71/701 - B01D71/702
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0002—Organic membrane manufacture
- B01D67/0006—Organic membrane manufacture by chemical reactions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/10—Supported membranes; Membrane supports
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention provides a hollow fiber nanofiltration membrane and a preparation method thereof, and the preparation method comprises the following steps: s1: using a hollow fiber ultrafiltration membrane as a base membrane, and soaking the base membrane in a cross-linking agent solution; s2: dipping the base film subjected to the step S1 in a first polymerization reaction solution containing a first polymerization reactant and a crosslinking reactant capable of crosslinking with the crosslinking agent; s3: dipping the base film subjected to the step S2 in a second polymerization reaction solution, wherein the first polymerization reactant and the second polymerization reaction solution are subjected to polymerization reaction to form a separation layer on the surface of the base film; s4: and carrying out heat treatment on the base membrane with the separation layer on the surface to obtain the hollow fiber nanofiltration membrane. The invention effectively strengthens the binding force between the base membrane and the separation layer and ensures the performance stability of the hollow fiber nanofiltration membrane.
Description
Technical Field
The invention relates to the technical field of preparation of separation membranes, in particular to a hollow fiber nanofiltration membrane and a preparation method thereof.
Background
The nanofiltration membrane is a membrane material with special separation function, the pore size of the membrane is between 1 and 10 nanometers, the pore size range allows monovalent salt ions such as sodium, potassium and the like to penetrate (the retention rate is less than or equal to 50 percent), and the nanofiltration membrane has better removal rate on divalent or polyvalent ions and organic matters with the molecular weight between 200 and 1000. In view of the special separation scale of the nanofiltration membrane, the nanofiltration membrane can be used in the fields of water softening (calcium and magnesium ion interception), detoxification (microorganism and heavy metal interception), purification and concentration of special chemical raw materials (such as dye, medicine and biomass) and oil-water separation. Meanwhile, the nanofiltration membrane still has higher flux under lower pressure (0.2-1MPa), so that the operation and maintenance cost is effectively saved. The nanofiltration membrane is suitable for large-scale urban tap water treatment and has important significance for drinking water safety guarantee.
The current mainstream nanofiltration membrane is formed by compounding a selective separation layer (mostly polyamide material) on the surface of a flat ultrafiltration membrane by an interfacial polymerization method and then rolling a membrane sheet into a membrane element. However, such composite rolled elements have structural limitations: 1) modules such as a water collecting pipe, a separation net, an inter-membrane supporting net and the like are also arranged in the roll-type element besides the membrane, so that the membrane space is greatly occupied, the filling density of the membrane is limited, and the water production efficiency is restricted; 2) pollutants in the narrow flow channel are not easy to wash out, and are easy to cause pollution blockage after long-time operation, so that the requirement on the quality of inlet water is high, an ultramicro filter membrane is often required to be introduced as a pretreatment process, and the operation cost of the nanofiltration membrane process is increased.
Compared with the roll type membrane, the hollow fiber membrane belongs to a self-supporting structure, a supporting device is not needed when the membrane element is assembled, and the unit fiber occupies a small space, so that the area of the filling membrane in the element is larger, and the water production efficiency is obviously improved compared with the roll type membrane. In addition, the hollow fiber structure has good pressure tolerance, can be washed by strong impact, and has better pollution resistance. Therefore, the hollow fiber nanofiltration membrane has great application potential in many fields.
However, the radian of the interface between the base membrane and the separation layer is large, so that the hollow fiber nanofiltration membrane cannot release stress well, and the separation layer is easy to fall off from the base membrane after long-term operation, thereby affecting the service performance of the membrane. Therefore, it is required to develop a high-performance hollow fiber nanofiltration membrane which can effectively overcome the above technical problems.
Disclosure of Invention
The invention aims to provide a hollow fiber nanofiltration membrane and a preparation method thereof, which can effectively enhance the binding force between a base membrane and a separation layer and ensure the performance stability of the hollow fiber nanofiltration membrane.
In order to achieve the purpose, the technical scheme of the invention is as follows: the invention provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
s1: using a hollow fiber ultrafiltration membrane as a base membrane, putting the base membrane into a cross-linking agent solution for dipping, and adsorbing a cross-linking agent on the surface of the base membrane;
s2: dipping the base film subjected to the step S1 in a first polymerization reaction solution containing a first polymerization reactant and a crosslinking reactant capable of crosslinking with the crosslinking agent;
s3: dipping the base film subjected to the step S2 in a second polymerization reaction solution, wherein the first polymerization reactant and the second polymerization reaction solution are subjected to polymerization reaction to form a separation layer on the surface of the base film; the reaction speed of the cross-linking agent and the cross-linking reactant is very slow at normal temperature, and the polymerization reaction is basically not influenced.
S4: and carrying out heat treatment on the base membrane with the separation layer on the surface to obtain the hollow fiber nanofiltration membrane. Under the action of high temperature, on one hand, the cross-linking agent and the cross-linking reactant generate cross-linking reaction, the cross-linked cross-linking reactant has good adhesion capability and stability, the binding force between the separation layer and the base membrane is enhanced, and the separation layer is not easy to fall off; on the other hand, heating is advantageous to relieve the stress of the film itself.
Optionally, the crosslinking reactant is a macromolecular compound with hydroxyl or primary amino on the surface. Macromolecular compounds generally refer to compounds having a relatively high molecular weight of several thousand to several million. The high molecular compound has more crosslinking sites and better crosslinking stability.
Optionally, the crosslinking reactant is polyethyleneimine or polyvinyl alcohol. The use cost of the polyethyleneimine and the polyvinyl alcohol is low, and the production cost of the hollow fiber nanofiltration membrane can be reduced.
Alternatively, the weight average molecular weight of the polyethyleneimine is 3000-50000. Alternatively, the weight average molecular weight of the polyethyleneimine is 8000-30000.
Optionally, the degree of alcoholysis of the polyvinyl alcohol is from 80 mol% to 100 mol%. The polyvinyl alcohol with alcoholysis degree within the range has higher hydroxyl group density, and effectively improves the bonding strength of the separation layer and the base film after the crosslinking reaction. Optionally, the degree of alcoholysis of the polyvinyl alcohol is from 87 mol% to 89 mol% or from 98 mol% to 99 mol%.
Optionally, the mass percentage concentration of the crosslinking reactant in the first polymerization reaction solution is 0.05% to 0.3%. In the concentration range, the crosslinking reactant can effectively cover the base membrane, and the pore channels of the base membrane are not blocked. Optionally, the mass percentage concentration of the crosslinking reactant in the first polymerization reaction solution is 0.1% to 0.2%.
Optionally, the first polymeric reactant is a polyamine. Optionally, the polyamine is a small molecule polyamine. Any molecule with a molecular weight less than 500 is referred to as a small molecule. The separation layer formed by the small molecular polyamine participating in the polymerization reaction has better compactness and pressure resistance.
Optionally, the mass percentage concentration of the first polymerization reactant in the first polymerization reaction solution is 0.2% to 2%. The separation layer formed by the first polymerization reactant in the concentration range participating in the polymerization reaction has better compactness. Optionally, the mass percentage concentration of the first polymerization reactant in the first polymerization reaction solution is 0.4% to 1%.
Optionally, the polyamine is at least one of piperazine, meta-phenylenediamine and para-phenylenediamine.
Optionally, the base membrane is immersed in the cross-linking agent solution for 5 to 10 minutes.
Optionally, the base membrane is placed in the cross-linking agent solution for a soaking time of 6-8 minutes.
Optionally, the base film is immersed in the first polymerization reaction solution for 1 to 10 minutes.
Optionally, the base film is immersed in the first polymerization reaction solution for 6 to 8 minutes.
Optionally, the base film is immersed in the second polymerization reaction solution for a time of 1 to 8 minutes.
Optionally, the base film is immersed in the second polymerization reaction solution for a time of 1 to 3 minutes.
Optionally, the second polymerization reaction solution is a polyacyl chloride organic solution.
Optionally, the poly-acid chloride organic solution comprises an aromatic ring-containing poly-acid chloride, the poly-acid chloride organic solution comprises at least one of isophthaloyl dichloride, terephthaloyl dichloride, and trimesoyl chloride, and the solvent in the poly-acid chloride organic solution is at least one of pentane, hexane, cyclohexane, and heptane. The separation layer formed by the aromatic ring-containing polyacyl chloride participating in the polymerization reaction has better compactness and pressure resistance.
Optionally, the concentration of the polyacyl chloride organic solution is 0.1% to 0.5%. The separation layer formed by the poly-acyl chloride organic solution in the concentration range participating in the polymerization reaction has better compactness.
Optionally, the concentration of the polyacyl chloride organic solution is 0.1% to 0.3%.
Optionally, the duration of the heat treatment is 2-30 minutes, and the temperature used for the heat treatment is 40-140 ℃.
Optionally, the duration of the heat treatment is 5-20 minutes, and the temperature adopted by the heat treatment is 60-120 ℃; or the temperature adopted by the heat treatment is 80-100 ℃. The heat treatment temperature can ensure that the crosslinking reaction can be effectively carried out, and simultaneously, the activity of the crosslinking agent and the crosslinking reactant is not damaged.
Optionally, the step S4 further includes: and (3) washing the hollow fiber nanofiltration membrane.
Optionally, the crosslinker solution comprises an aldehyde crosslinker.
Optionally, the aldehyde crosslinker comprises at least one of glutaraldehyde, adipaldehyde, and succinaldehyde. The aldehyde cross-linking agent with small molecular weight has higher activity, but the stability of the aldehyde cross-linking agent is influenced when the molecular weight is too small, and the glutaraldehyde, the hexanedial and the succinaldehyde have both smaller molecular weight and stability.
Optionally, the mass percentage concentration of the cross-linking agent solution is 0.05% -1%. The cross-linking agent solution with the concentration range can ensure that the cross-linking agent solution and the cross-linking reactant are effectively cross-linked, and can also effectively prevent the cross-linking agent solution and the cross-linking reactant from being excessively cross-linked to cause membrane blockage.
Optionally, the cross-linking agent solution has a mass percentage concentration of 0.1% to 0.25%.
Optionally, the hollow fiber ultrafiltration membrane is made of one of polyamide, polyacrylonitrile, polysulfone and polyvinylidene fluoride.
The invention also provides the hollow fiber nanofiltration membrane prepared by the preparation method of the hollow fiber nanofiltration membrane, which comprises a supporting layer, an adhesive layer and a separation layer which are sequentially arranged, wherein the separation layer is fixed on the supporting layer through the adhesive layer, and the adhesive layer is obtained through a cross-linking reaction.
The invention provides a hollow fiber nanofiltration membrane and a preparation method thereof. Compared with the prior art, the method has the advantages that the base membrane is pretreated by using the cross-linking agent, the cross-linking reactant is added into the subsequent reaction solution participating in the polymerization reaction, the heat treatment is carried out on the base membrane after the polymerization reaction is finished on the surface of the base membrane and the separation layer is formed, and under the action of high temperature, the cross-linking reactant has good adhesion capability and stability after the cross-linking reaction with the cross-linking agent, so that the binding force between the base membrane and the separation layer is greatly enhanced.
Detailed Description
The present invention will be described in detail with reference to the following embodiments in order to make the aforementioned objects, features and advantages of the invention more comprehensible.
Example 1
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, using a polyamide hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, soaking the base membrane in glutaraldehyde solution for 5 minutes, taking out the base membrane, and vertically hanging the base membrane for 10 minutes. Wherein, the glutaraldehyde solution is prepared by mixing 0.05g of glutaraldehyde and 100mL of water. The molecular weight cut-off of the polyamide hollow fiber ultrafiltration membrane in this example was 30000.
Step 2: the base film having completed the step 1 was immersed in an aqueous reaction solution (first polymerization reaction solution, the same shall apply hereinafter) for 1 minute, and then taken out to hang vertically for 1 minute, and then excess aqueous reaction solution liquid on the surface thereof was removed. The aqueous reaction solution in this example was prepared by mixing 0.05g of polyethyleneimine having a weight average molecular weight of 3000, 0.2g of m-phenylenediamine, and 100mL of water.
And step 3: and (3) soaking the base membrane subjected to the step 2 in an isophthaloyl dichloride organic solution (a second polymerization reaction solution) for 1 minute, taking out the base membrane, and then placing the base membrane into a 60-DEG C air-blast drying oven to keep the temperature for 5 minutes to obtain the hollow fiber nanofiltration membrane. Wherein the isophthaloyl dichloride solution is prepared by mixing 0.1g of isophthaloyl dichloride and 100mL of pentane.
The base membrane and the separation layer are swelled to different degrees after being treated by the alcohol solvent, so that the interface bonding force of the base membrane and the separation layer is influenced. The method comprises the following specific steps:
firstly, placing the prepared hollow fiber nanofiltration membrane in an environment with the temperature of 25 ℃ and the pressure of 0.3MPa, and using MgSO with the concentration of 0.2%4The electrolyte solution is used for testing the interception performance and the water flux of a test water sample to obtain a test result: desalinationThe rate was 92.3%, and the water flux was 16.7L/m2h。
Then, in this example, the hollow fiber nanofiltration membrane after the above test is placed in an ethanol solution for soaking treatment for 1 hour, and the volume fraction of the ethanol solution is 50%. After washing, the retention performance and the water flux of the water-washing agent are tested by the same method as the above method, and the test result is obtained: the salt rejection rate is 91.7 percent, and the water flux is 19.3L/m2h。
For comparison, in this embodiment, three control groups are selected, and the bonding strength between the basement membrane and the separation layer is tested by the same method as above:
first control group: the hollow fiber nanofiltration membrane is prepared without pretreatment of an aldehyde crosslinking agent solution, a crosslinking reactant is not added into an aqueous phase reaction solution, and other reaction conditions are consistent with those of the hollow fiber nanofiltration membrane prepared in the embodiment. The salt rejection rates before and after ethanol soaking of the first control group were 97.8% and 64.4%, respectively.
Second control group: the hollow fiber nanofiltration membrane is prepared by pretreating with an aldehyde cross-linking agent solution, but no cross-linking reactant is added into the aqueous phase reaction solution, and other reaction conditions are consistent with those of the embodiment. The second control group had a salt rejection of 96.5% to 59.7% after ethanol soaking.
Third control group: the aldehyde cross-linking agent solution is not pretreated, the cross-linking reactant is added into the water phase reaction solution, and the hollow fiber nanofiltration membrane is prepared under the other reaction conditions consistent with the conditions of the embodiment. The salt rejection rate of the third control group after ethanol soaking was changed from 96.1% to 61.6%.
In conclusion, the difference of the salt rejection of the hollow fiber nanofiltration membrane obtained by the preparation method provided by the embodiment before and after ethanol soaking is small, and the salt rejection of the three control groups after ethanol soaking is obviously reduced to different degrees. It can be seen that the preparation method provided by the embodiment can effectively improve the bonding strength between the separation layer on the hollow fiber nanofiltration membrane and the base membrane, and the separation layer is not easy to fall off. Meanwhile, tests show that the hollow fiber nanofiltration membrane prepared by the embodiment has higher water flux and better service performance.
Example 2
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, using a polyacrylonitrile hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, soaking the base membrane in a succinaldehyde solution for 10 minutes, taking out the base membrane, and vertically hanging the base membrane for 20 minutes. Wherein the succinaldehyde solution is prepared by mixing 0.25g of succinaldehyde with 100mL of water. The molecular weight cut-off of the polyacrylonitrile hollow fiber ultrafiltration membrane in the embodiment is 50000.
Step 2: the base film having completed the step 1 was immersed in the aqueous reaction solution for 10 minutes, and then taken out to hang vertically for 10 minutes, and then the excess aqueous reaction solution liquid on the surface thereof was removed. The aqueous reaction solution in this example was prepared by mixing 0.3g of polyethyleneimine, 2g of p-phenylenediamine, and 100mL of water, and the weight average molecular weight of the polyethyleneimine was 50000.
And step 3: and (3) putting the base membrane subjected to the step 2 into a terephthaloyl chloride organic solution, soaking for 8 minutes, taking out, and then putting the base membrane into a 120-DEG C forced air drying oven to keep the temperature for 20 minutes to obtain the hollow fiber nanofiltration membrane. In this example, the terephthaloyl chloride organic solution was formed by mixing 0.5g terephthaloyl chloride with 100mL hexane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the salt rejection rate is changed from 94.5 percent to 93.1 percent, and the water flux is changed from 18.8L/m2h is changed to 20.5L/m2h。
Example 3
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, taking a polyvinylidene fluoride hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, putting the cleaned base membrane into a glutaraldehyde solution, soaking for 8 minutes, taking out the cleaned base membrane, and vertically hanging for 15 minutes. Wherein, the glutaraldehyde solution is prepared by mixing 0.1g of glutaraldehyde and 100mL of water. The molecular weight cut-off of the polyvinylidene fluoride hollow fiber ultrafiltration membrane in the embodiment is 40000.
Step 2: the base film having completed the step 1 was immersed in the aqueous reaction solution for 5 minutes, and then taken out to hang vertically for 5 minutes, and then excess aqueous reaction solution liquid on the surface thereof was removed. In this example, the aqueous reaction solution was prepared by mixing 0.1g of polyethyleneimine, 1g of piperazine and 100mL of water, and the weight average molecular weight of the polyethyleneimine was 10000.
And step 3: and (3) putting the base membrane subjected to the step 2 into a trimesoyl chloride organic solution, soaking for 4 minutes, taking out, and then putting the base membrane into a forced air drying oven at 80 ℃ for 10 minutes to obtain the hollow fiber nanofiltration membrane. In this example, trimesoyl chloride organic solution was prepared by mixing 0.3g of trimesoyl chloride with 100mL of cyclohexane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the salt rejection rate is changed from 96.4 percent to 93.7 percent, and the water flux is changed from 18.4L/m2h becomes 21.7/m2h。
Example 4
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, taking a polysulfone hollow fiber ultrafiltration membrane as a base membrane, washing the base membrane with pure water, putting the base membrane into a hexanedial solution for soaking for 6 minutes, taking out the base membrane, and vertically hanging and airing for 10 minutes. Wherein the adipic dialdehyde solution is prepared by mixing 0.25g of adipic dialdehyde with 100mL of water. The cut-off molecular weight of the polysulfone hollow fiber ultrafiltration membrane in this example was 30000.
Step 2: the base film which completed step 1 was immersed in the aqueous reaction solution for 7 minutes, and then taken out to hang vertically for 7 minutes, and then excess aqueous reaction solution liquid on the surface thereof was removed. The aqueous reaction solution in this example was prepared by mixing 0.2g of polyethyleneimine, 1.5g of p-phenylenediamine, and 100mL of water, and the weight average molecular weight of the polyethyleneimine was 30000.
And step 3: and (3) putting the base membrane subjected to the step 2 into an isophthaloyl dichloride organic solution, soaking for 6 minutes, taking out, and then putting the base membrane into a blast drying oven at 100 ℃ for keeping for 15 minutes to obtain the hollow fiber nanofiltration membrane. The isophthaloyl dichloride organic solution of this example was prepared by mixing 0.4g isophthaloyl dichloride with 100mL heptane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the salt rejection rate is changed from 93.2 percent to 91.7 percent, and the water flux is changed from 20.3L/m2h becomes 23.4/m2h。
Example 5
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, using a polyacrylonitrile hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, putting the cleaned base membrane into a glutaraldehyde solution, soaking the cleaned base membrane for 10 minutes, taking the cleaned base membrane out, and vertically hanging the cleaned base membrane for 20 minutes. Wherein, the glutaraldehyde solution is prepared by mixing 0.1g of glutaraldehyde and 100mL of water. The molecular weight cut-off of the polyacrylonitrile hollow fiber ultrafiltration membrane in this example was 30000.
Step 2: the base film having completed the step 1 was immersed in the aqueous reaction solution for 6 minutes, and then taken out to hang vertically for 10 minutes, and then the excess aqueous reaction solution liquid on the surface thereof was removed. The aqueous reaction solution in this example was prepared by mixing 0.05g of polyethyleneimine, 0.5g of piperazine and 100mL of water, and the weight average molecular weight of the polyethyleneimine was 40000.
And step 3: and (3) putting the base membrane subjected to the step 2 into a trimesoyl chloride organic solution, soaking for 4 minutes, taking out, and then putting the base membrane into a 90-DEG C forced air drying oven to keep for 5 minutes to obtain the hollow fiber nanofiltration membrane. In this example, trimesoyl chloride organic solution was prepared by mixing 0.2g of trimesoyl chloride with 100mL of pentane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the salt rejection rate is changed from 96.2 percent to 95.8 percent, and the water flux is changed from 16.3L/m2h becomes 20.8/m2h。
Example 6
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, using a polyamide hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, soaking the base membrane in a glutaraldehyde solution for 10 minutes, taking out the base membrane, and vertically hanging the base membrane for 10 minutes. Wherein, the glutaraldehyde solution is prepared by mixing 0.1g of glutaraldehyde and 100mL of water. The molecular weight cut-off of the polyamide hollow fiber ultrafiltration membrane in this example was 40000.
Step 2: the base film having completed the step 1 was immersed in the aqueous reaction solution for 8 minutes, and then taken out to hang vertically for 10 minutes, and then excess aqueous reaction solution liquid on the surface thereof was removed. The aqueous reaction solution of this example was mixed with 0.25g of polyethyleneimine having a molecular weight of 5000, 2g of p-phenylenediamine, and 100mL of water.
And step 3: and (3) putting the base membrane subjected to the step 2 into a terephthaloyl chloride organic solution, soaking for 8 minutes, taking out, and then putting the base membrane into a 60-DEG C forced air drying oven to keep the temperature for 20 minutes to obtain the hollow fiber nanofiltration membrane. In this example, the terephthaloyl chloride organic solution was formed by mixing 0.4g terephthaloyl chloride with 100mL hexane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the salt rejection rate is changed from 94.7 percent to 93.2 percent, and the water flux is changed from 21.6L/m2h becomes 23.4/m2h。
Example 7
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, taking a polyvinylidene fluoride hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, putting the cleaned base membrane into a glutaraldehyde solution, soaking for 8 minutes, taking out the cleaned base membrane, and vertically hanging for 15 minutes. Wherein, the glutaraldehyde solution is prepared by mixing 0.1 glutaraldehyde and 100mL water. The molecular weight cut-off of the polyamide hollow fiber ultrafiltration membrane in this example was 30000.
Step 2: the base film having completed the step 1 was immersed in the aqueous reaction solution for 10 minutes, and then taken out to hang vertically for 10 minutes, and then the excess aqueous reaction solution liquid on the surface thereof was removed. The aqueous reaction solution of this example was mixed with 0.1g of polyethyleneimine having a molecular weight of 8000, 1.5g of piperazine and 100mL of water.
And step 3: and (3) putting the base membrane subjected to the step 2 into an isophthaloyl dichloride organic solution, soaking for 8 minutes, taking out, and then putting the base membrane into a forced air drying oven at 80 ℃ for 10 minutes to obtain the hollow fiber nanofiltration membrane. The isophthaloyl dichloride organic solution of this example was prepared by mixing 0.5g isophthaloyl dichloride with 100mL heptane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the desalination rate is changed from 97.3 percent to 95.8 percent, and the water flux is changed from 15.3L/m2h becomes 17.9/m2h。
Example 8
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, using a polyamide hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, soaking the base membrane in glutaraldehyde solution for 5 minutes, taking out the base membrane, and vertically hanging the base membrane for 10 minutes. Wherein, the glutaraldehyde solution is prepared by mixing 0.05 glutaraldehyde and 100mL water. The molecular weight cut-off of the polyamide hollow fiber ultrafiltration membrane in this example was 30000.
Step 2: the base film which has completed step 1 is immersed in the aqueous reaction solution for 1 minute, and then taken out to hang vertically for 1 minute, and then excess aqueous reaction solution liquid on the surface thereof is removed. In this example, the aqueous reaction solution was prepared by mixing 0.2g of polyvinyl alcohol, 0.2g of m-phenylenediamine and 100mL of water, and the alcoholysis degree of the polyvinyl alcohol was 88 mol%.
And step 3: and (3) putting the base membrane subjected to the step 2 into an isophthaloyl dichloride organic solution, soaking for 1 minute, taking out, and then putting the base membrane into a 60-DEG C forced air drying oven to keep for 5 minutes to obtain the hollow fiber nanofiltration membrane. The isophthaloyl dichloride organic solution of this example was prepared by mixing 0.1g isophthaloyl dichloride with 100mL pentane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the desalination rate is changed from 97.4 percent to 95.1 percent, and the water flux is changed from 15.5L/m2h becomes 18.9L/m2h。
Example 9
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, taking a polysulfone hollow fiber ultrafiltration membrane as a base membrane, washing the base membrane with pure water, soaking the base membrane in a succinaldehyde solution for 10 minutes, taking out the base membrane, and vertically hanging and airing the base membrane for 20 minutes. Wherein the succinaldehyde solution is prepared by mixing 0.25 of succinaldehyde with 100mL of water. The molecular weight cut-off of the polysulfone hollow fiber ultrafiltration membrane in this example was 40000.
Step 2: the base film having completed the step 1 was immersed in the aqueous reaction solution for 10 minutes, and then taken out to hang vertically for 10 minutes, and then the excess aqueous reaction solution liquid on the surface thereof was removed. In this example, the aqueous reaction solution was prepared by mixing 0.1g of polyvinyl alcohol, 0.4g of piperazine and 100mL of water, and the degree of alcoholysis of the polyvinyl alcohol was 98 mol%.
And step 3: and (3) putting the base membrane subjected to the step 2 into a terephthaloyl chloride organic solution, soaking for 8 minutes, taking out, and then putting the base membrane into a 120-DEG C forced air drying oven to keep the temperature for 20 minutes to obtain the hollow fiber nanofiltration membrane. In this example, the terephthaloyl chloride organic solution was formed by mixing 0.3g terephthaloyl chloride with 100mL hexane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the salt rejection rate is changed from 95.6 percent to 93.1 percent, and the water flux is changed from 16.3L/m2h is changed to 19.1L/m2h。
Example 10
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, taking a polyvinylidene fluoride hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, putting the cleaned base membrane into a glutaraldehyde solution, soaking for 8 minutes, taking out the cleaned base membrane, and vertically hanging for 15 minutes. Wherein, the glutaraldehyde solution is prepared by mixing 0.15 glutaraldehyde and 100mL water. The molecular weight cut-off of the polyvinylidene fluoride hollow fiber ultrafiltration membrane in the embodiment is 40000.
Step 2: the base film having completed the step 1 was immersed in the aqueous reaction solution for 5 minutes, and then taken out to hang vertically for 5 minutes, and then excess aqueous reaction solution liquid on the surface thereof was removed. In this example, the aqueous reaction solution was prepared by mixing 0.2g of polyvinyl alcohol, 2g of p-phenylenediamine and 100mL of water, and the degree of alcoholysis of the polyvinyl alcohol was 89 mol%.
And step 3: and (3) putting the base membrane subjected to the step 2 into a trimesoyl chloride organic solution, soaking for 4 minutes, taking out, and then putting the base membrane into a forced air drying oven at 100 ℃ for 10 minutes to obtain the hollow fiber nanofiltration membrane. In this example, trimesoyl chloride was mixed with 0.5g of trimesoyl chloride and 100mL of heptane to form an organic solution.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the salt rejection rate is changed from 96.3 percent to 94.5 percent, and the water flux is changed from 17.1L/m2h becomes 20.8/m2h。
Example 11
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, taking a polysulfone hollow fiber ultrafiltration membrane as a base membrane, washing the base membrane with pure water, putting the base membrane into a hexanedial solution for soaking for 6 minutes, taking out the base membrane, and vertically hanging and airing for 10 minutes. Wherein the adipic dialdehyde solution is prepared by mixing 0.2g of adipic dialdehyde with 100mL of water. The cut-off molecular weight of the polysulfone hollow fiber ultrafiltration membrane in this example was 30000.
Step 2: the base film which completed step 1 was immersed in the aqueous reaction solution for 7 minutes, and then taken out to hang vertically for 7 minutes, and then excess aqueous reaction solution liquid on the surface thereof was removed. In this example, the aqueous reaction solution was prepared by mixing 0.1g of polyvinyl alcohol, 1g of m-phenylenediamine and 100mL of water, and the degree of alcoholysis of the polyvinyl alcohol was 99 mol%.
And step 3: and (3) putting the base membrane subjected to the step 2 into an isophthaloyl dichloride organic solution, soaking for 6 minutes, taking out, and then putting the base membrane into a 90-DEG C forced air drying oven to keep for 15 minutes to obtain the hollow fiber nanofiltration membrane. The isophthaloyl dichloride organic solution of this example was prepared by mixing 0.3g isophthaloyl dichloride with 100mL cyclohexane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the desalination rate is changed from 97.4 percent to 95.1 percent, and the water flux is changed from 15.5L/m2h is changed to 19.6L/m2h。
Example 12
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, using a polyacrylonitrile hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, putting the cleaned base membrane into a glutaraldehyde solution, soaking the cleaned base membrane for 10 minutes, taking the cleaned base membrane out, and vertically hanging the cleaned base membrane for 20 minutes. Wherein, the glutaraldehyde solution is prepared by mixing 0.1g of glutaraldehyde and 100mL of water. The molecular weight cut-off of the polyacrylonitrile hollow fiber ultrafiltration membrane in this example was 30000.
Step 2: the base film after completion of step 1 was immersed in the aqueous reaction solution for 6 minutes, taken out and hung vertically for 10 minutes, and then excess aqueous reaction solution liquid on the surface thereof was removed. In this example, the aqueous reaction solution was prepared by mixing 0.08g of polyvinyl alcohol, 0.8g of piperazine and 100mL of water, and the degree of alcoholysis of the polyvinyl alcohol was 98 mol%.
And step 3: and (3) putting the base membrane subjected to the step (2) into the terephthaloyl chloride organic solution, soaking for 4 minutes, taking out, and then putting the base membrane into a forced air drying oven at the temperature of 90 ℃ to keep the temperature for 5 minutes to obtain the hollow fiber nanofiltration membrane. In this example, the terephthaloyl chloride organic solution was formed by mixing 0.4g terephthaloyl chloride with 100mL hexane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the salt rejection rate is changed from 95.3 percent to 92.7 percent, and the water flux is changed from 20.7L/m2h is changed to 24.5L/m2h。
Example 13
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, using a polyamide hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, soaking the base membrane in a glutaraldehyde solution for 10 minutes, taking out the base membrane, and vertically hanging the base membrane for 10 minutes. Wherein, the glutaraldehyde solution is prepared by mixing 0.05g of glutaraldehyde and 100mL of water. The molecular weight cut-off of the polyamide hollow fiber ultrafiltration membrane in this example was 40000.
Step 2: the base film having completed the step 1 was immersed in the aqueous reaction solution for 8 minutes, and then taken out to hang vertically for 10 minutes, and then excess aqueous reaction solution liquid on the surface thereof was removed. In this example, the aqueous reaction solution was prepared by mixing 0.2g of polyvinyl alcohol, 1g of p-phenylenediamine, and 100mL of water, and the degree of alcoholysis of the polyvinyl alcohol was 87 mol%.
And step 3: and (3) putting the base membrane subjected to the step 2 into a trimesoyl chloride organic solution, soaking for 8 minutes, taking out, then putting the base membrane into a 60-DEG C forced air drying oven, keeping for 8 minutes, and finally washing to obtain the hollow fiber nanofiltration membrane. In this example, trimesoyl chloride was mixed with 0.3g of trimesoyl chloride and 100mL of heptane to form an organic solution.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the salt rejection rate is changed from 98.1 percent to 96.9 percent, and the water flux is 12.5L/m2h becomes 16.9L/m2h。
Example 14
The embodiment provides a preparation method of a hollow fiber nanofiltration membrane, which comprises the following steps:
step 1, taking a polyvinylidene fluoride hollow fiber ultrafiltration membrane as a base membrane, cleaning the base membrane with pure water, putting the cleaned base membrane into a glutaraldehyde solution, soaking for 8 minutes, taking out the cleaned base membrane, and vertically hanging for 15 minutes. Wherein, the glutaraldehyde solution is prepared by mixing 0.1g of glutaraldehyde and 100mL of water. The molecular weight cut-off of the polyvinylidene fluoride hollow fiber ultrafiltration membrane in the example is 30000.
Step 2: the base film having completed the step 1 was immersed in the aqueous reaction solution for 10 minutes, and then taken out to hang vertically for 10 minutes, and then the excess aqueous reaction solution liquid on the surface thereof was removed. In this example, the aqueous reaction solution was prepared by mixing 0.05g of polyvinyl alcohol, 2g of piperazine and 100mL of water, and the degree of alcoholysis of the polyvinyl alcohol was 88 mol%.
And step 3: and (3) putting the base membrane subjected to the step 2 into a trimesoyl chloride organic solution, soaking for 8 minutes, taking out, and then putting the base membrane into a 90-DEG C forced air drying oven to keep for 10 minutes to obtain the hollow fiber nanofiltration membrane. In this example, trimesoyl chloride organic solution was prepared by mixing 0.2g of trimesoyl chloride with 100mL of cyclohexane.
In this embodiment, the bonding strength between the base membrane and the separation layer of the obtained hollow fiber nanofiltration membrane is tested, and the test method is the same as that in the first embodiment, so that the test result is obtained: the salt rejection rate is changed from 94.3 percent to 92.4 percent, and the water flux is changed from 21.8L/m2h becomes 25.7L/m2h。
It will be apparent to those skilled in the art that various changes and modifications may be made in the invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (17)
1. A preparation method of a hollow fiber nanofiltration membrane is characterized by comprising the following steps:
s1: using a hollow fiber ultrafiltration membrane as a base membrane, and soaking the base membrane in a cross-linking agent solution;
s2: dipping the base film subjected to the step S1 in a first polymerization reaction solution containing a first polymerization reactant and a crosslinking reactant capable of crosslinking with the crosslinking agent; the crosslinking reactant is a macromolecular compound with hydroxyl or primary amino on the surface; the first polymerization reactant is polyamine;
s3: dipping the base film subjected to the step S2 in a second polymerization reaction solution, wherein the first polymerization reactant and the second polymerization reaction solution are subjected to polymerization reaction to form a separation layer on the surface of the base film;
s4: and carrying out heat treatment on the base membrane with the separation layer on the surface to obtain the hollow fiber nanofiltration membrane.
2. The method for preparing a hollow fiber nanofiltration membrane according to claim 1, wherein the crosslinking reactant is polyethyleneimine or polyvinyl alcohol.
3. The method for preparing a hollow fiber nanofiltration membrane according to claim 2, wherein the weight average molecular weight of the polyethyleneimine is 3000-50000.
4. The method of claim 2, wherein the degree of alcoholysis of the polyvinyl alcohol is between 80 and 100 mol%.
5. The method for preparing a hollow fiber nanofiltration membrane according to claim 1 or 2, wherein the mass percentage concentration of the cross-linking reactant in the first polymerization reaction solution is 0.05-0.3%.
6. The method for preparing a hollow fiber nanofiltration membrane according to claim 1, wherein the polyamine is a small molecule polyamine.
7. The method for preparing a hollow fiber nanofiltration membrane according to claim 6, wherein the polyamine is at least one of piperazine, m-phenylenediamine and p-phenylenediamine.
8. The method for preparing a hollow fiber nanofiltration membrane according to claim 1, wherein the mass percentage concentration of the first polymerization reactant in the first polymerization reaction solution is 0.2-2%.
9. The method for preparing a hollow fiber nanofiltration membrane according to claim 1, wherein the second polymerization reaction solution is a polybasic acid chloride organic solution.
10. The method for preparing a hollow fiber nanofiltration membrane according to claim 9, wherein the poly-acid chloride organic solution comprises a poly-acid chloride containing aromatic rings.
11. The method for preparing a hollow fiber nanofiltration membrane according to claim 10, wherein the poly-acid chloride organic solution comprises at least one of isophthaloyl dichloride, terephthaloyl dichloride, and trimesoyl dichloride.
12. The method for preparing a hollow fiber nanofiltration membrane according to any one of claims 9 to 11, wherein the mass percentage concentration of the polyacyl chloride organic solution is 0.1% to 0.5%.
13. The method for preparing a hollow fiber nanofiltration membrane according to claim 1, wherein the temperature adopted for the heat treatment is 60 ℃ to 120 ℃.
14. The method of claim 1, wherein the cross-linking agent solution comprises an aldehyde cross-linking agent.
15. The method of claim 14, wherein the aldehyde cross-linking agent comprises at least one of glutaraldehyde, adipaldehyde, and succinaldehyde.
16. The method for preparing a hollow fiber nanofiltration membrane according to claim 1, wherein the mass percentage concentration of the cross-linking agent solution is 0.05-1%.
17. A hollow fiber nanofiltration membrane prepared by the method of any one of claims 1 to 16, comprising a support layer, an adhesive layer, and a separation layer sequentially arranged, wherein the separation layer is fixed on the support layer by the adhesive layer, and the adhesive layer is obtained by a crosslinking reaction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811562140.2A CN111346526B (en) | 2018-12-20 | 2018-12-20 | Hollow fiber nanofiltration membrane and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811562140.2A CN111346526B (en) | 2018-12-20 | 2018-12-20 | Hollow fiber nanofiltration membrane and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111346526A CN111346526A (en) | 2020-06-30 |
| CN111346526B true CN111346526B (en) | 2022-04-22 |
Family
ID=71188201
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811562140.2A Active CN111346526B (en) | 2018-12-20 | 2018-12-20 | Hollow fiber nanofiltration membrane and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111346526B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112915809A (en) * | 2021-01-27 | 2021-06-08 | 常州市美纤膜技术有限公司 | Civil hollow fiber nanofiltration membrane and preparation method thereof |
| CN115193269A (en) * | 2021-04-14 | 2022-10-18 | 西陇科学股份有限公司 | Preparation method of high-flux fine hollow fiber nanofiltration membrane for purifying drinking water |
| CN115155339A (en) * | 2022-06-29 | 2022-10-11 | 杭州奈诺膜环境技术有限公司 | Hollow fiber nanofiltration membrane and preparation method thereof |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6605391B2 (en) * | 1999-02-26 | 2003-08-12 | Reveo, Inc. | Solid gel membrane |
| JP4989843B2 (en) * | 2001-07-20 | 2012-08-01 | マクマスター ユニヴァーシティ | Asymmetric gel-filled microporous membrane |
| CN101524626A (en) * | 2008-03-07 | 2009-09-09 | 浙江欧美环境工程有限公司 | External pressure type hollow fiber nano filtering film and preparation method thereof |
| CN103480278B (en) * | 2013-09-06 | 2015-02-25 | 烟台绿水赋膜材料有限公司 | Preparation method and application of anti-pollution hydrophilic separating membrane |
| CN106310972A (en) * | 2016-10-17 | 2017-01-11 | 天津膜天膜科技股份有限公司 | Hollow fiber nanofiltration membrane and preparation method thereof |
| CN107837689B (en) * | 2017-09-25 | 2020-10-27 | 浙江理工大学 | Preparation method of composite nanofiltration membrane with ultrathin separation layer |
-
2018
- 2018-12-20 CN CN201811562140.2A patent/CN111346526B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN111346526A (en) | 2020-06-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108905624B (en) | Polyester-polyamide amphoteric charge composite nanofiltration membrane and preparation method thereof | |
| CN111346526B (en) | Hollow fiber nanofiltration membrane and preparation method thereof | |
| CN105435653B (en) | A kind of composite nanometer filtering film to divalent ion removing with high selectivity and preparation method thereof | |
| CN112023727B (en) | Anti-pollution antibacterial reverse osmosis membrane, preparation method and application thereof | |
| EP2883600A2 (en) | Polyamide-based water-treatment separation membrane having excellent salt removal rate and permeation flux characteristics and method for manufacturing same | |
| CN109351190A (en) | It is a kind of to be crosslinked the compound solvent resistant nanofiltration membrane of fluorine-containing polyamide, preparation method and applications | |
| CN112535955B (en) | Decolorizing membrane and preparation method and application thereof | |
| CN103785297A (en) | Composite nanofiltration membrane containing organically modified attapulgite and preparation method thereof | |
| CN112870990B (en) | Antibacterial and pollution-resistant reverse osmosis composite membrane and preparation method thereof | |
| CN104548952A (en) | Preparation method of antibacterial compound nanofiltration film | |
| CN111790276A (en) | Preparation method of alkali-resistant nanofiltration composite membrane | |
| CN110917907A (en) | High-flux reverse osmosis membrane and preparation method and application thereof | |
| CN114713042B (en) | Nanofiltration membrane with high resolution and water flux and preparation method thereof | |
| CN115554849A (en) | Preparation method of polyethyleneimine-based positively-charged nanofiltration membrane | |
| CN114642967B (en) | Nanofiltration membrane based on reactive supporting layer, preparation method and application | |
| CN113230888A (en) | Polyethyleneimine modified nanofiltration membrane and preparation method thereof | |
| CN112426884A (en) | Antibacterial composite reverse osmosis membrane and preparation method thereof | |
| CN102814126A (en) | Preparation method of high-flux antioxidant nanofiltration membrane | |
| CN114887486A (en) | Mannitol-based polyester loose composite nanofiltration membrane and preparation method and application thereof | |
| CN110394065B (en) | Composite nanofiltration membrane and preparation method and application thereof | |
| CN112370976B (en) | Interface enhanced composite nanofiltration membrane and preparation method thereof | |
| CN110354682B (en) | Reverse osmosis membrane resisting biological pollution and preparation method and application thereof | |
| CN102188916A (en) | Method for controlling thickness of active layer of polyamide composite membrane | |
| CN111318186A (en) | Method for improving pollution resistance of composite reverse osmosis membrane | |
| KR102041657B1 (en) | Method for manufacturing water-treatment membrane, water-treatment membrane manufactured by thereof, and water treatment module comprising membrane |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information |
Address after: Building 1-3, 619 Caifeng Road, Huzhou City, Zhejiang Province, 313000 Applicant after: Euro American new materials (Zhejiang) Co.,Ltd. Address before: No.688 Xifeng Road, Huzhou Economic and Technological Development Zone, Huzhou City, Zhejiang Province, 313000 Applicant before: OCHEMATE MATERIAL TECHNOLOGIES Co.,Ltd. |
|
| CB02 | Change of applicant information | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |