CN-121972135-A - Preparation method of superhydrophobic monoatomic Cu porous polymer ammonia separation material

CN121972135ACN 121972135 ACN121972135 ACN 121972135ACN-121972135-A

Abstract

The invention discloses a preparation method of a super-hydrophobic single-atom Cu porous polymer ammonia separation material. The material is prepared by copolymerizing divinylbenzene and 4-vinyl pyridine to construct a super-hydrophobic porous framework, and anchoring monoatomically dispersed copper species by using pyridine nitrogen groups to form strong adsorption sites. The preparation method has simple process and easily obtained raw materials. The material has super-hydrophobic surface and high-density monoatomic copper sites, has extremely high adsorption capacity and selectivity for ammonia, can particularly effectively inhibit competitive adsorption of water molecules in a high-humidity environment, keeps excellent ammonia trapping performance and cycle stability, and has wide application prospects in the fields of synthesis gas purification, ammonia-containing waste gas treatment, ammonia energy purification and the like.

Inventors

LIU FUJIAN
CHEN CAIHUA
JIANG LILONG
Zhong Shouchao
ZHENG YONG

Assignees

福州大学

Dates

Publication Date: 20260505
Application Date: 20260225

Claims (10)

1. A preparation method of a super-hydrophobic single-atom Cu porous polymer ammonia separation material is characterized in that a super-hydrophobic polymer skeleton is formed by copolymerizing monomers of divinylbenzene and 4-vinylpyridine, the super-hydrophobic polymer skeleton is obtained by coordination and loading of pyridine nitrogen groups and copper species which are highly dispersed in a single-atom form, the specific surface area of the ammonia separation material is 50-350 m 2 /g, and the copper species are dispersed on the surfaces of polymer pore channels and the skeleton in the single-atom form.
2. The method for preparing the superhydrophobic monoatomic Cu porous polymer ammonia separation material according to claim 1, comprising the steps of: (1) The carrier synthesis comprises dissolving divinylbenzene DVB, 4-vinylpyridine VP and initiator azobisisobutyronitrile AIBN in organic solvent, performing solvothermal polymerization reaction, volatilizing the product at normal temperature and pressure to remove the solvent after the reaction, and vacuum drying to obtain the super-hydrophobic porous organic polymer carrier with pyridine nitrogen groups; (2) Constructing a monoatomic copper site, namely placing the carrier obtained in the step (1) and a copper source into an absolute ethyl alcohol solvent, and stirring at room temperature to obtain a mixed solution; (3) And (3) post-treatment, namely carrying out suction filtration on the mixed solution obtained in the step (2), washing the obtained solid by using absolute ethyl alcohol, carrying out suction filtration again, and then drying the solid product in a constant-temperature drying oven to obtain the super-hydrophobic monoatomic Cu porous polymer ammonia separation material.
3. The method for preparing the superhydrophobic monoatomic Cu porous polymer ammonia separation material according to claim 2, wherein in the step (1), the organic solvent is one of tetrahydrofuran, ethyl acetate and ethanol, and the mass ratio of DVB, VP, AIBN is 1:0.5-2:0.03-0.1.
4. The method for preparing the superhydrophobic monoatomic Cu porous polymer ammonia separation material according to claim 2, wherein the solvothermal polymerization reaction in the step (1) is carried out at a temperature of 100-140 ℃, the reaction time is 24-72 h, the volatilization time is 12-24 h, the vacuum drying temperature is 60-100 ℃, and the vacuum drying time is 12-24 h.
5. The method for preparing a superhydrophobic monoatomic Cu porous polymer ammonia separation material according to claim 2, wherein the copper source in step (2) is one selected from copper chloride dihydrate, copper sulfate pentahydrate and copper nitrate trihydrate.
6. The method for preparing the superhydrophobic monoatomic Cu porous polymer ammonia separation material according to claim 2, wherein the mass ratio of the porous organic polymer carrier to the copper source in the step (2) is 0.1-0.5, and the stirring time is 1-6 h.
7. The method for preparing the superhydrophobic monoatomic Cu porous polymer ammonia separation material according to claim 2, wherein the drying temperature in the step (3) is 80-120 ℃ and the drying time is 24-72 h.
8. The superhydrophobic monoatomic Cu porous polymer ammonia separation material made by the method of any one of claims 1-7.
9. The use of the superhydrophobic single-atom Cu porous polymer ammonia separation material according to claim 8 in ammonia selective adsorption separation.
10. The method according to claim 9, wherein the adsorption temperature is 25-75 ℃, the adsorption pressure is 0-1.0 bar, the ammonia adsorption separation is carried out under the humidity range of RH=50-80%, the ammonia desorption temperature is 120-160 ℃, and the desorption pressure is 0-0.1 bar.

Description

Preparation method of superhydrophobic monoatomic Cu porous polymer ammonia separation material Technical Field The invention belongs to the technical field of functional polymer materials and gas adsorption separation, and particularly relates to a super-hydrophobic single-atom Cu porous polymer ammonia separation material, and a preparation method and application thereof as a moisture-resistant high-performance ammonia adsorbent. Background Ammonia (NH 3) is an indispensable chemical foundation stone and an emerging green energy carrier. The carbon-free fuel and the hydrogen energy transmission medium are not only important raw materials for manufacturing chemical fertilizers, foods and medicines, but also are regarded as carbon-free fuels and hydrogen energy transmission media with huge potential for realizing carbon neutralization due to the high hydrogen content (the mass hydrogen storage density reaches 17.6 wt percent), the easy liquefying and storing characteristics and the advantage of no carbon dioxide generated by combustion. NH 3 is not only an important chemical raw material, but also a toxic pollutant, and forms a threat to ecology and human health. As the main alkaline gas in the atmosphere, NH 3 is easy to react with acidic substances (such as SO 2) to generate ammonium salt, which becomes one of key precursors of PM 2.5, SO that the atmospheric visibility is reduced, and the ecological environment is also endangered. Ammonia is irritating to the human body, can damage eyes, skin and respiratory tract, and high concentration exposure can even endanger life. Therefore, the realization of the efficient and economic capturing and separating of the ammonia gas is a key link of the resource utilization and pollution control. Currently, the mainstream ammonia capture technology includes absorption, adsorption, membrane separation, and the like. The adsorption method has the advantages of mild operation conditions, relatively low energy consumption, easiness in realizing cyclic regeneration and the like, and ammonia gas can be captured and reused by the adsorption method. However, the traditional porous adsorbent such as zeolite has been widely used in the ammonia adsorption field due to the advantages of various pore structures, low cost, easily available raw materials, etc., but has limited ammonia adsorption capacity and low selectivity. The key is that the surface of the material lacks strong chemical adsorption sites, particularly in a humid environment, water molecules in the pore canal can strongly compete with ammonia to adsorb sites, so that the performance of the material is drastically reduced, and the practical application is severely limited. As an emerging adsorbent, metal organic framework Materials (MOFs) have the advantages of high porosity and adjustable structure, and have excellent initial adsorption performance on ammonia, but the framework is composed of coordination bonds, so that the chemical stability is insufficient, the structure collapse or irreversible adsorption is easy to occur in a high-humidity or strong-alkaline ammonia environment, the cycle life is short, and the problems of high synthesis cost and difficult large-scale preparation exist. Porous Organic Polymers (POPs) are novel porous materials with rich pore structures and good stability, which mainly consist of C, H, O, N and other light elements, the preparation method of the porous organic polymers is flexible, the structural modifier is strong, the structural stability is high, the porous organic polymers can be repeatedly used for ammonia capture, but the surface of the porous organic polymers is generally lack of active sites with strong specific interaction with ammonia molecules, and the porous organic polymers mainly depend on physical adsorption, so that the adsorption capacity and the selectivity are to be improved. Therefore, it is important to develop a novel adsorbent material that can simultaneously overcome the above-mentioned drawbacks. The invention designs a synergistic strategy for combining a monoatomic copper active site and a super-hydrophobic polymer skeleton, which realizes high-capacity and high-selectivity chemical adsorption by utilizing the strong specific coordination action of monoatomic copper and ammonia molecules, and simultaneously, effectively repels water molecules and protects the active site by utilizing the super-hydrophobic skeleton formed by divinylbenzene crosslinking, thereby ensuring the adsorption performance and structural stability of the material in a humid environment. Disclosure of Invention The invention provides a preparation method of a super-hydrophobic single-atom Cu porous polymer ammonia separation material, which aims to solve the problems of suddenly reduced performance, low active site utilization rate, poor stability and the like of the existing ammonia adsorption material in a wet environment. The material prevents water molecules from condensing in