CN-121975427-A - Anti-scaling coating resistant to medium and high hydrothermal temperature as well as preparation method and application thereof

Abstract

The invention discloses a preparation method of an anti-scaling coating resistant to medium and high hydrothermal temperatures, which comprises the following steps of fixedly supporting an anti-scaling agent in nano mesoporous silica with the size of 70-90 nm, the specific surface area of >600 m 2 /g and the aperture of 2-9 nm to obtain nano silica for fixedly supporting the anti-scaling agent, uniformly mixing the nano silica with particles of heat-resistant polymer resin in a physical blending mode, and carrying out electrostatic spraying on a substrate, so as to obtain the anti-scaling coating resistant to medium and high hydrothermal temperatures after high-temperature curing. The nano mesoporous silica adopted in the invention has good adsorption capacity, the scale inhibitor can be immobilized in the nano mesoporous silica through physical adsorption, the nano silica immobilized with the scale inhibitor and the heat-resistant polymer resin are physically mixed and cured to prepare the scale-resistant coating, the scale-resistant coating has excellent scale resistance, is economical and has stronger environmental protection, and the scale-resistant effect of the material surface in the medium-high temperature hydrothermal environment can be realized without a large amount of the addition of the scale inhibitor.

Inventors

• HU WENHUI
• LI QUANDE
• HU JIMING
• ZHANG ZHONGWEI
• GONG XIUFANG
• MA YI

Assignees

• 浙江大学
• 中国东方电气集团有限公司
• 东方电气长三角(杭州)创新研究院有限公司

Dates

Publication Date

20260505

Application Date

20260126

Claims (10)

1. 1. The preparation method of the scale preventing coating resistant to the medium and high hydrothermal temperature is characterized by comprising the following steps of: (1) Putting the nano mesoporous silica and the scale inhibitor into a solvent, and heating and refluxing to react to obtain nano silica of the immobilized scale inhibitor; The size of the nano mesoporous silica is 70-90 nm, the specific surface area is more than 600 m 2 /g, and the aperture is 2-9 nm; (2) Uniformly mixing nano silicon dioxide of the solid-supported anti-scaling agent obtained in the step (1) with particles of heat-resistant polymer resin in a physical blending mode, and carrying out electrostatic spraying on a substrate, so as to obtain the anti-scaling coating resistant to medium and high hydrothermal temperature after high-temperature solidification.
2. 2. The method for preparing the scale preventing coating resistant to the medium and high hydrothermal temperatures according to claim 1, wherein in the step (1), the preparation method of the nano mesoporous silica is characterized in that cetyl trimethyl ammonium bromide is dissolved in an aqueous solution of sodium hydroxide, tetraethoxysilane is added, nano silica with a template is obtained after heating and stirring, and the nano mesoporous silica is obtained after grinding and dispersing in an ethanol solution of acid to remove the cetyl trimethyl ammonium bromide template.
3. 3. The method for preparing the scale preventing coating resistant to the medium and high hydrothermal temperature according to claim 1, wherein the mass ratio of the nano mesoporous silica to the scale inhibitor is 1:1-6.
4. 4. The method for producing a medium and high hydrothermal temperature resistant antifouling coating according to claim 1, wherein in step (1), the antifouling agent is a phosphonic antifouling agent and a carboxylic antifouling agent, the phosphonic antifouling agent is at least one of hydroxyethylidene diphosphonic acid, polyamino ether methylenephosphonic acid, bis 1, 6-hexylidene triamine pentamethylene phosphonic acid, and the carboxylic antifouling agent is polyepoxysuccinic acid.
5. 5. The method for producing a scale control coating layer against medium and high hydrothermal temperatures according to claim 4, wherein the mass ratio of the phosphonic acid scale control agent to the carboxylic acid scale control agent is 1 to 5:1.
6. 6. The method for preparing the scale preventing coating resistant to the medium and high hydrothermal temperatures according to claim 1, wherein in the step (1), a silane coupling agent is further added in the preparation process of the nano silicon dioxide carrying the scale preventing agent, and the silane coupling agent is one or more of 3-aminopropyl triethoxysilane, N-aminoethyl-3-aminopropyl triethoxysilane and 3-aminopropyl trimethoxysilane.
7. 7. The method for preparing the anti-scaling coating resistant to the medium and high hydrothermal temperatures according to claim 6, wherein the mass ratio of the silane coupling agent to the nano mesoporous silica is 1:1-6.
8. 8. The method for preparing a middle and high hydrothermal temperature resistant antifouling coating according to claim 1, wherein in the step (2), the heat resistant polymer resin is one or more of polybenzoxazine, polyphenylene sulfide, polyether ether ketone, polytetrafluoroethylene and polysulfone.
9. 9. The method for preparing a scale control coating resistant to medium and high hydrothermal temperatures according to claim 1, wherein in the step (2), the mass ratio of the heat resistant polymer resin to the nano silica carrying the scale control agent is 100:1-5.
10. 10. The scale preventing coating resistant to medium and high hydrothermal temperatures, which is prepared by the preparation method according to any one of claims 1 to 9.

Description

Anti-scaling coating resistant to medium and high hydrothermal temperature as well as preparation method and application thereof Technical Field The invention relates to the technical field of scale prevention of geothermal water environment equipment, in particular to a scale prevention coating resistant to medium and high hydrothermal temperatures, and a preparation method and application thereof. Background Clean green energy sources such as geothermal water, nuclear power stations and the like are often in a high-temperature high-pressure water environment system, the service environment of structural metal of the clean green energy sources has severe temperature and pressure, the chemical components of water quality are very complex, calcium ions, silicic acid and the like are easy to scale, the scale is often supersaturated and separated out along with the rise of temperature and pressure, and thus the scaling problem of equipment, pipelines, pipes and the like is very serious. Up to now, the common scale inhibition or removal methods include chemical agent methods, high-pressure water spraying cleaning methods, etc., but these methods tend to easily pollute geothermal water resources or consume large manpower and material resources. The chemical agent method is to add the scale inhibitor directly into the environment solution, the scale inhibitor can effectively prevent the growth of scale, and the scale forming cation concentration is inhibited from further increasing by forming stable complex with the scale forming cation, so that the scale preventing effect is achieved. However, since the solution in the actual environment continuously flows, the method needs to continuously supplement the antiscaling agent, so that the large-scale added agent itself causes environmental pollution, and the method is not a long-term and efficient green treatment means. Reference 1（Dong Yuhua, et al. A novel anti-scaling and protection coating based on hollow periodic mesoporous organosilica encapsulated with scale inhibitor. Progress in Organic Coatings, 2025, 199: 108942） discloses a method for preparing a composite material of immobilized scale inhibitor, which encapsulates the scale inhibitor ethylenediamine tetramethylphosphonic acid (EDTMP) with Hollow Periodic Mesoporous Organosilicon (HPMO), and the encapsulation slows down the release rate of EDTMP, thereby prolonging the sustained release time of the scale inhibitor and enabling the coating to have long-term scale inhibition effect. According to the method, the HPMO is subjected to amino functional group modification, so that the loading rate of the scale inhibitor is further improved, and the coating material is finally applied to an epoxy coating. However, the research still has limitations, on one hand, HPMO materials are core-shell structures with large sizes of about 350: 350 nm, agglomeration is easier to occur, so that exposed adsorption sites are relatively fewer, the solid load rate of the scale inhibitor is further reduced, the method is complicated in additional construction of cavities, the method does not meet the requirements of green development, and on the other hand, the epoxy coating is a hydrophilic coating and has poor performance in the field of hydrothermal environment, and particularly has insufficient applicability in the aspect of scale prevention. The surface of the coating is susceptible to localized damage under the attack of the hydrothermal extremes, forming nucleation sites for fouling and causing severe fouling build-up. Geothermal water environment has severe requirements on the coating, so that common organic coatings such as epoxy coatings are difficult to meet the requirements. How to utilize the coating method to scale control or retard the rate of scaling is a technology to be developed in the geothermal or nuclear fields. The water-heat resistant coating developed by researchers takes heat resistant polymer resin as a main body, and most composite materials select nano materials with large specific surface area and stability during immobilization, but the nano materials cannot be uniformly dispersed due to compatibility problem, and the prepared coating has fine gaps and is easy to be penetrated by water molecules. Therefore, it is important to develop a molecular immobilization technology of an antiscaling agent which has good compatibility with heat-resistant resin and can be stable in a high-temperature and high-pressure water environment for a long time, and the prepared coating still has good antiscaling effect in the severe environment. Disclosure of Invention In order to solve the technical problems, the invention provides the preparation method of the scale-proof coating resistant to the medium-high hydrothermal temperature, the prepared scale-proof coating is excellent in scale-proof performance, economical and high in environmental protection, and the scale-proof effect of the surface of the material in the