CN115253694B - Membrane scale inhibitor, preparation method and application thereof - Google Patents
Membrane scale inhibitor, preparation method and application thereof Download PDFInfo
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- CN115253694B CN115253694B CN202210912809.6A CN202210912809A CN115253694B CN 115253694 B CN115253694 B CN 115253694B CN 202210912809 A CN202210912809 A CN 202210912809A CN 115253694 B CN115253694 B CN 115253694B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D65/00—Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
- B01D65/08—Prevention of membrane fouling or of concentration polarisation
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/58—Treatment of water, waste water, or sewage by removing specified dissolved compounds
- C02F1/60—Silicon compounds
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
- C02F5/08—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents
- C02F5/10—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances
- C02F5/12—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances containing nitrogen
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2321/00—Details relating to membrane cleaning, regeneration, sterilization or to the prevention of fouling
- B01D2321/16—Use of chemical agents
- B01D2321/168—Use of other chemical agents
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- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
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- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention discloses a membrane scale inhibitor and a preparation method and application thereof, and belongs to the technical field of polymer synthesis. The invention synthesizes a novel membrane scale inhibitor containing a large amount of carboxyl and amino by copolymerizing a modified monomer with acrylic acid and a crosslinking agent. The carboxyl contained in the molecular chain of the membrane scale inhibitor provided by the invention can effectively prevent metal ions from forming scale, the contained amino has a very strong inhibition effect on the formation of silica scale, and a proper amount of cross-linking agent can promote the branching degree of a product, so that the membrane scale inhibitor has the characteristics of shearing resistance and temperature resistance.
Description
Technical Field
The invention relates to the technical field related to polymer synthesis, in particular to a membrane scale inhibitor, a preparation method and application thereof.
Background
The membrane technology is a common water treatment method, has the characteristics of low cost, convenience and high efficiency, and is widely used in various industries. The catalyst is often used together with a scale inhibitor to prevent metal ions such as calcium, magnesium and the like and silicon dioxide in the wastewater from crystallizing into scale on the surface of the membrane after the wastewater is concentrated in the water treatment process, so that membrane pores are blocked, and the service efficiency, period and service life of the membrane are reduced.
With the need of environmental protection and the development of technology, traditional phosphorus-containing scale inhibitors are gradually replaced by organic polymers containing carboxylate, sulfonate and other anionic groups, such as polyacrylic acid and copolymers thereof, polyaspartic acid, polyepoxysuccinic acid and the like. The polymers containing anionic groups can chelate with metal ions to generate lattice distortion and disperse crystal nucleus, so that metal ion scaling is effectively inhibited, but the scale inhibitor has weak inhibiting capability on silicon scale with negative charges, especially when the pH value is higher, the formed silicic acid or monosilicic acid can react with high-valence metal ions to produce silicate which is difficult to dissolve in water, and the efficiency of the scale inhibitor is reduced. In addition, the membrane can be reused after cleaning, and the scale formed by metal ions can be removed by dilute hydrochloric acid and the like, but the cleaning of the silica scale is difficult, the damage of the cleaned membrane is large, and the separation efficiency is greatly reduced.
Therefore, a scale inhibitor capable of inhibiting scaling of metal ions and avoiding formation of silica scale is needed.
Disclosure of Invention
In order to solve the existing technical problems. The invention provides a preparation method of a membrane scale inhibitor, which comprises the following steps:
adding 35-45 parts of acrylic acid monomer, 0-3 parts of cross-linking agent, a part of deionized water, 0.5-2.5 parts of initiator and 2-6 parts of chain transfer agent into a reaction container according to parts by weight, uniformly mixing and dissolving, and regulating the pH to 6-8 to form uniform solution;
II, adding another part of deionized water and modified monomer into the reaction vessel, starting stirring and heating to 75-90 ℃; wherein the total parts of deionized water in the step I and the step II are 25-55 parts;
and III, dripping the solution into the reactor at a constant speed until the dripping is completed, and cooling to below 35 ℃ to obtain the membrane scale inhibitor.
Preferably or alternatively, the modified monomer has a structure as shown in formula (1):
wherein,
R 1 h, CH of a shape of H, CH 3 Or CH (CH) 2 CH 3 One or more of the following;
R 2 is H or CH 2 CH 2 NH 2 One or more of the following;
R 3 h, CH of a shape of H, CH 2 CH 2 NH 2 、One or more of the following.
Preferably or alternatively, in the modified monomer structure, R 4 Is CH 2 CH 2 NH 2 、
One or more of the following.
Preferably or alternatively, the cross-linking agent is one or more of N, N-methylenebisacrylamide, N-methylolacrylamide and polyallylamine.
Preferably or alternatively, the initiator is one or more of potassium persulfate, sodium persulfate or ammonium persulfate.
Preferably or alternatively, the chain transfer agent is one or more of sodium formate, ammonium formate, ethanol, isopropanol, sodium bisulphite.
A membrane scale inhibitor is prepared by the preparation method of the membrane scale inhibitor.
The membrane scale inhibitor prepared by the preparation method of the membrane scale inhibitor is applied to the field of membrane treatment wastewater with high silicon content and high hardness.
The beneficial effects are that: the invention prepares a membrane scale inhibitor, and in the synthesis process, the acrylic acid monomer serving as a matrix has good metal ion scale inhibition effect due to a large number of carboxyl groups, and can play roles of chelating, dispersing and causing lattice distortion. After the monomer containing amino groups is copolymerized and modified, the inhibiting capability of the scale inhibitor on silicon deposit can be greatly improved, silicon dioxide in water carries negative charge through hydration ionization, amino groups in a molecular chain segment carry positive charge through protonation, and the amino groups and the negatively charged silicon dioxide can play a role in solubilizing the silicon dioxide through electrostatic interaction, so that the supersaturation degree of the silicon dioxide is improved, and the effect of inhibiting the scaling of the silicon dioxide is achieved. In addition, a small amount of cross-linking agent is added in the preparation of the membrane scale inhibitor, and the scale inhibitor provided by the invention has a branched structure through light cross-linking, so that a good scale inhibition effect can be maintained in a high-shear and high-pressure environment. Meanwhile, the preparation process does not contain phosphorus element, and is more environment-friendly.
Detailed Description
In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the invention may be practiced without one or more of these details. In other instances, well-known features have not been described in detail in order to avoid obscuring the invention.
The invention is further illustrated below in conjunction with examples, examples of which are intended to illustrate the invention and are not to be construed as limiting the invention. The specific techniques and reaction conditions not specified in the examples may be carried out according to the techniques or conditions described in the literature in this field or the product specifications. Reagents, instruments or equipment not specifically mentioned in the manufacturer are commercially available.
Example 1
(1) 46g of acrylic acid, 1.18g of potassium persulfate, 3.5g of sodium formate, 1.5g of N, N-methylenebisacrylamide and 50g of deionized water are mixed and dissolved to form a uniform solution;
(2) Adding 25g of deionized water and 3g of modified monomer into a reactor, starting stirring and heating to 85 ℃;
(3) Slowly and uniformly dripping the solution into a reactor until the dripping is completed, and cooling to 30 ℃ to obtain the membrane scale inhibitor with 42.3% of solid content.
Example 2
(1) 42g of acrylic acid, 1.18g of potassium persulfate, 3.8g of sodium formate, 3g of N, N-methylenebisacrylamide and 50g of deionized water are mixed and dissolved to form a uniform solution;
(2) Adding 25g of deionized water and 3g of modified monomer into a reactor, starting stirring and heating to 85 ℃;
(3) Slowly and uniformly dripping the solution into a reactor until the dripping is completed, and cooling to 30 ℃ to obtain the membrane scale inhibitor with the solid content of 41.6%.
Example 3
(1) 44g of acrylic acid, 1.12g of ammonium persulfate, 3.5g of ammonium formate, 1.5g of N, N-methylenebisacrylamide and 50g of deionized water were mixed and dissolved to form a uniform solution;
(2) Adding 25g of deionized water and 6g of modified monomer into a reactor, starting stirring and heating to 85 ℃;
(3) Slowly and uniformly dripping the solution into a reactor until the dripping is completed, and cooling to 30 ℃ to obtain the membrane scale inhibitor with the solid content of 43.0%.
Example 4
(1) 42g of acrylic acid, 1.13g of ammonium persulfate, 3.8g of ammonium formate, 3g of N, N-methylenebisacrylamide and 50g of deionized water are mixed and dissolved to form a uniform solution;
(2) Adding 25g of deionized water and 6g of modified monomer into a reactor, starting stirring and heating to 85 ℃;
(3) Slowly and uniformly dripping the solution into a reactor until the dripping is completed, and cooling to 30 ℃ to obtain the membrane scale inhibitor with 42.9% of solid content.
Example 5
(1) 40g of acrylic acid, 1.15g of ammonium persulfate, 3.6g of ammonium formate, 1.5g of N, N-methylenebisacrylamide and 50g of deionized water are mixed and dissolved to form a uniform solution;
(2) Adding 25g of deionized water and 10g of modified monomer into a reactor, starting stirring and heating to 85 ℃;
(3) Slowly and uniformly dripping the solution into a reactor until the dripping is completed, and cooling to 30 ℃ to obtain the membrane scale inhibitor with the solid content of 43.1%.
Example 6
(1) 38g of acrylic acid, 1.15g of ammonium persulfate, 4.2g of ammonium formate, 3g of N, N-methylenebisacrylamide and 50g of deionized water were mixed and dissolved to form a uniform solution;
(2) Adding 25g of deionized water and 12g of modified monomer into a reactor, starting stirring and heating to 85 ℃;
(3) Slowly and uniformly dripping the solution into a reactor until the dripping is completed, and cooling to 30 ℃ to obtain the membrane scale inhibitor with the solid content of 43.4%.
Comparative example 1
(1) Mixing 40g of acrylic acid, 1.14g of ammonium persulfate, 3.9g of ammonium formate and 50g of deionized water for dissolution to form a uniform solution;
(2) Adding 25g of deionized water and 10g of modified monomer into a reactor, starting stirring and heating to 85 ℃;
(3) Slowly and uniformly dripping the solution into a reactor until the dripping is completed, and cooling to 30 ℃ to obtain the membrane scale inhibitor with 42.5% of solid content.
Comparative example 2
(1) 48g of acrylic acid, 1.23g of potassium persulfate, 3.5g of sodium formate and 50g of deionized water are mixed and dissolved to form a uniform solution;
(2) Adding 25g of deionized water into a reactor, starting stirring and heating to 85 ℃;
(3) Slowly and uniformly dripping the solution into a reactor until the dripping is completed, and cooling to 30 ℃ to obtain the membrane scale inhibitor with the solid content of 41.5%.
Comparative example 3
(1) 47g of acrylic acid, 1.06g of ammonium persulfate, 3.7g of ammonium formate, 1.5g of N, N-methylenebisacrylamide and 50g of deionized water were mixed and dissolved to form a uniform solution;
(2) Adding 25g of deionized water into a reactor, starting stirring and heating to 85 ℃;
(3) Slowly and uniformly dripping the solution into a reactor until the dripping is completed, and cooling to 30 ℃ to obtain the membrane scale inhibitor with the molecular weight solid content of 42.1%.
And (3) scale inhibition test:
calcium scale inhibition rate: sequentially adding a certain amount of CaCl into a 100mL volumetric flask 2 Solution, diluted scale inhibitor solution and NaHCO 3 Adding deionized water to the solution to a volume of 100mL, wherein the solution contains 500mg/L calcium hardness (CaCO concentration) 3 Meter), 10mg/L scale inhibitor concentration and 500mg/L alkalinity, while blank test was performed; and placing the sample in a 40 ℃ incubator, taking supernatant after 2 days, diluting, titrating the calcium ion concentration, and calculating the scale inhibition rate.
Scale inhibition rate of silica scale: sequentially adding a certain amount of Na into a 100mL volumetric flask 2 SiO 3 The solution and the diluted scale inhibitor solution are adjusted to pH 7, deionized water is added to constant volume to 100mL, and the solution contains 500mg/L silicon concentration (the concentration is SiO 2 Meter) and a scale inhibitor concentration of 10 mg/L; sample the samplePlacing in a 40 ℃ incubator, taking supernatant after 2 days, diluting, and adopting a molybdenum blue colorimetric method to measure SiO in the sample 2 And calculating the content and the scale inhibition rate.
Scale inhibition = [ (C) 1 -C 0 )/(500-C 0 )]×100％
Wherein C is 0 The calcium concentration or the silicon concentration in the water sample after the blank test; c (C) 1 The calcium concentration or the silicon concentration in the water sample after the scale inhibitor is added for testing.
The specific test results are shown in the following table:
as apparent from the evaluation results in the table, the membrane scale inhibitors prepared in examples 1 to 6 prepared by the means of the invention have good calcium scale inhibition capability while greatly improving the silicon scale inhibition performance in comparison examples.
In addition, the specific features described in the above embodiments may be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the various q-possible combinations are not described in detail.
Claims (7)
1. The preparation method of the membrane scale inhibitor comprises the following steps:
adding 35-45 parts of acrylic acid monomer, 3 parts of cross-linking agent, a part of deionized water, 0.5-2.5 parts of initiator and 2-6 parts of chain transfer agent into a reaction container according to parts by weight, uniformly mixing and dissolving, and adjusting the pH to 6-8 to form uniform solution;
II, adding another part of deionized water and modified monomer into the reaction vessel, starting stirring and heating to 75-90 ℃; wherein the total parts of deionized water in the step I and the step II are 25-55 parts;
III, dripping the solution into a reactor at a constant speed until the dripping is completed, and cooling to below 35 ℃ to obtain the membrane scale inhibitor;
the modified monomer has a structure shown in a formula (1):
（1）；
wherein,
R 1 h, CH of a shape of H, CH 3 Or CH (CH) 2 CH 3 One or more of the following;
R 2 is H or CH 2 CH 2 NH 2 One or more of the following;
R 3 h, CH of a shape of H, CH 2 CH 2 NH 2 、One or more of the following.
2. The method for producing a membrane scale inhibitor according to claim 1, wherein in the modified monomer structure, R 4 Is CH 2 CH 2 NH 2 、One or more of the following.
3. The method for preparing a membrane scale inhibitor according to claim 1, wherein the cross-linking agent is one or more of N, N-methylenebisacrylamide, N-methylolacrylamide, polyallylamine.
4. The method for preparing a membrane scale inhibitor according to claim 1, wherein the initiator is one or more of potassium persulfate, sodium persulfate or ammonium persulfate.
5. The method for preparing a membrane scale inhibitor according to claim 1, wherein the chain transfer agent is one or more of sodium formate, ammonium formate, ethanol, isopropanol, and sodium bisulfate.
6. A membrane scale inhibitor, characterized by being prepared by the method for preparing a membrane scale inhibitor according to any one of claims 1 to 5.
7. The application of the membrane scale inhibitor prepared by the preparation method of the membrane scale inhibitor according to any one of claims 1-5 is characterized in that the membrane scale inhibitor is applied to the field of membrane treatment wastewater with high silicon content and high hardness.
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| JPH10314794A (en) * | 1997-05-20 | 1998-12-02 | Kurita Water Ind Ltd | Scale inhibitor |
| CN1496338A (en) * | 2001-03-15 | 2004-05-12 | Ge ���Ĺ�˾ | Method for controlling scale formation and deposition in aquesous systems |
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| CN109180509A (en) * | 2018-06-25 | 2019-01-11 | 上海龙灯环保科技有限公司 | Trimethylolpropane tris ((N, N- bis- (2- amino-ethyl)) -3- aminopropan acid esters) and preparation method and application |
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| CN111286068A (en) * | 2020-02-12 | 2020-06-16 | 东北电力大学 | Method for preparing hydrophilic-hydrophobic composite membrane by grafting zwitterion on surface |
| CN113426303A (en) * | 2021-06-28 | 2021-09-24 | 深圳德蓝生态环境有限公司 | Reverse osmosis high-silicon scale inhibitor and preparation method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3655721B2 (en) * | 1996-12-04 | 2005-06-02 | 栗田工業株式会社 | Scale inhibitor |
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- 2022-07-31 CN CN202210912809.6A patent/CN115253694B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10314794A (en) * | 1997-05-20 | 1998-12-02 | Kurita Water Ind Ltd | Scale inhibitor |
| CN1496338A (en) * | 2001-03-15 | 2004-05-12 | Ge ���Ĺ�˾ | Method for controlling scale formation and deposition in aquesous systems |
| CN102076838A (en) * | 2008-06-30 | 2011-05-25 | 巴斯夫欧洲公司 | Amphoteric polymer for treating hard surfaces |
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| CN109133389A (en) * | 2018-10-12 | 2019-01-04 | 山东理工大学 | Non-phosphorus composite scale inhibitor |
| CN109592746A (en) * | 2018-12-28 | 2019-04-09 | 上海丰信环保科技有限公司 | Over-expense chain reverse osmosis antisludging agent of reticular structure and preparation method thereof and application |
| CN111286068A (en) * | 2020-02-12 | 2020-06-16 | 东北电力大学 | Method for preparing hydrophilic-hydrophobic composite membrane by grafting zwitterion on surface |
| CN113426303A (en) * | 2021-06-28 | 2021-09-24 | 深圳德蓝生态环境有限公司 | Reverse osmosis high-silicon scale inhibitor and preparation method thereof |
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