阅读说明：本技术 一种金属有机骨架泡沫材料及其制备方法和应用 (Metal organic framework foam material and preparation method and application thereof ) 是由 兰亚乾 陈勇军 陈宜法 王艺蓉 苗畅 于 2020-06-17 设计创作，主要内容包括：本发明公开了一种金属有机骨架泡沫材料及其制备方法和在微塑料过滤中的应用,本发明将Zr盐和对苯二甲酸或官能团取代的对苯二甲酸加入丙酮中混合,然后加入载体树脂材料,加热反应,冷却,洗涤,干燥,制备得到一系列具有互穿结构、MOF分布均匀、缺陷多、耐久性好的泡沫材料。该泡沫材料可以在水或者海水条件下实现对微塑料高效过滤,具有极大的水稳定以及海水稳定性,可适用于不同浓度的以及各种类型的微塑性过滤,展现了极大的通用性。值得注意的是,该材料的制备以及应用的开发,对于开发新型的微塑性过滤技术提供了极大的帮助,在未来解决海洋塑料污染问题有着广阔的应用前景。(The invention discloses a metal organic framework foam material, a preparation method thereof and application thereof in micro-plastic filtration. The foam material can realize the efficient filtration of the micro plastic under the condition of water or seawater, has great water stability and seawater stability, can be suitable for micro plastic filtration of different concentrations and various types, and shows great universality. The preparation and application development of the material provide great help for developing a novel micro-plastic filtration technology, and the material has wide application prospect in solving the problem of marine plastic pollution in the future.)

1. The preparation method of the metal organic framework foam material is characterized by comprising the following steps:

adding Zr salt and terephthalic acid or functional group substituted terephthalic acid into acetone for mixing, then adding a carrier resin material, heating for reaction, cooling, washing and drying to obtain the product.

2. The method of claim 1, wherein the Zr salt is selected from the group consisting of zirconium tetrachloride, zirconium oxychloride and zirconium nitrate.

3. The method of claim 1, wherein the functional group-substituted terephthalic acid is selected from the group consisting of 2, 5-dihydroxyterephthalic acid, 2-aminoterephthalic acid, 2-bromoterephthalic acid, and nitroterephthalic acid.

4. The method of claim 1, wherein the mass ratio of the Zr salt to the terephthalic acid or the functional group-substituted terephthalic acid is 1:1 to 1: 3.

5. The method of claim 1, wherein the carrier resin material is selected from melamine formaldehyde resin, phenol formaldehyde resin and polyolefin polymer.

6. The method for preparing the metal-organic framework foam material according to claim 1, wherein the heating reaction temperature is 80-110 ℃ and the heating time is 20-28 hours.

7. The method according to claim 1, wherein the amount of the metal-organic framework supported on the carrier in the metal-organic framework foam is 4.4 wt% to 25.4 wt%.

8. A metal-organic framework foam material obtained by the production method according to any one of claims 1 to 7.

9. Use of the metal organic framework foam material according to claim 8 in micro plastic filtration.

Technical Field

The invention relates to a Metal Organic Framework (MOFs) foam material, a preparation method thereof and application thereof in micro-plastic filtration, belonging to the technical field of metal organic framework foam materials.

Background

With the development of industry and the worldThe dramatic increase in population, human life and industrial production activities have brought about a large amount of waste plastics. The problem of pollution caused by waste plastics has become a huge environmental crisis facing society. In 2018, the total consumption of plastics is as high as about 80 hundred million tons, and only a small amount (about 9%) of the plastics is recycled. However, due to the strong chemical resistance properties of waste plastics, most of the waste plastics remain in the environment and can remain for a long period of time without being degraded. Some of these waste plastics that remain in the environment flow into the ocean and are broken down into microplastics by the mechanical action of the ocean waves and the biological action of the ocean environment. In 2004, the concept of "micro-plastics" was first proposed in published journals, defining plastic chips with a diameter of less than 5 mm as micro-plastics, which is also figuratively referred to as "PM in the sea"_2.5". The total amount of plastics produced worldwide is about 2.75 million tons per year, while about 500-1300 million tons per year flow from land into the ocean increases year by year, resulting in an increasing amount of micro-plastics in the ocean. In addition, some waste micro-plastics generated by human activities, such as micro-beads in detergent, plastic fragments of worn and remained road surface of tires, and fine synthetic fibers in waste water of washing machines, are directly generated by human activities, and also flow into water, even in the sea, further increasing the pollution crisis of the micro-plastics. There are studies showing that about 1.5-5.1X 10 in 2014¹²The block micro plastic floats on the sea, and the total weight of the block micro plastic is about 9.3 multiplied by 10⁴-2.36×10⁵Ton. Because of its small size and high specific surface area, the microplastic is very easy to adsorb pollutant (such as polychlorinated biphenyl or bisphenol A). The micro plastic which adsorbs the floating pollutants is easily ingested by animals such as plankton or seabird, and enters in vivo tissues even blood cells and the like. Meanwhile, the human body is positioned at the top end of the organic food chain, and the micro plastic is most likely to be transferred into the human body through the food chain and accumulated in the human body, thereby bringing unpredictable harm to human health. Therefore, the micro-plastics in the water body bring more serious harm, so that the ecological environment of the ocean is greatly polluted, and finally, the life health of human beings is necessarily harmed.

Although it is crucial to control the source of the micro-plastic in order to solve the problem of micro-plastic contamination, it is closely related to everyone in the world, requires a common effort among people all over the world, and requires a long time and several generations of people. In contrast, the development of new microplastic filtration technologies may be a more promising strategy that may play a role in time in mitigating the problem of microplastic contamination. The solid particles are filtered from the aqueous phase, and in the current art, the usual methods are mainly: typical filtration, microfiltration, ultrafiltration or nanofiltration and the like. For typical filtration techniques, filter paper is a commonly used material. However, the filter paper has relatively large filter pore size (20-25 μm), and may only filter out microposts of more than ten microns, and it is difficult to effectively filter out microposts of several microns or nanometers. For microfiltration (0.1-1 μm), ultrafiltration (2-100nm) or nanofiltration (. about.2 nm), while micro-or nano-sized microplastics can be filtered out, they have some disadvantages that cannot be improved, such as: 1) their small pore size may result in slower filtration rates and even plugging of the pores, which can be a significant impediment to large scale microplastic processing; 2) the filtration is often performed under high pressure, which may result in some energy consumption and higher cost, and 3) the recovery cycle is usually performed by high pressure back flushing, which greatly increases the difficulty and cost of recovery. In addition, although there have been some reports on micro-particle filtration in seawater, they mainly aim at fine sand having a particle size of more than 5 μm in seawater, and the method used is a rotating disk centrifugation method for filtration, and a large amount of energy is consumed. Few studies are known to report effective strategies for filtering microplastics. Therefore, the development of materials for solving the problem of micro plastic contamination has become an urgent problem to be solved.

Disclosure of Invention

The purpose of the invention is as follows: in order to solve the technical problems, the invention provides a Metal Organic Framework (MOFs) foam material, a preparation method and application thereof, aims to be applied to filtration of micro-plastics in water and provides an effective suggestion for solving marine plastic pollution.

The technical scheme is as follows: in order to achieve the purpose, the invention adopts the following technical scheme:

a preparation method of a metal organic framework foam material comprises the following steps:

adding Zr salt and terephthalic acid or functional group substituted terephthalic acid into acetone for mixing, then adding a carrier resin material, heating for reaction, cooling, washing and drying to obtain the product.

Preferably, the method comprises the following steps:

the Zr salt is selected from zirconium tetrachloride, zirconium oxychloride or zirconium nitrate.

The functional group-substituted terephthalic acid is selected from 2, 5-dihydroxyterephthalic acid, 2-aminoterephthalic acid, 2-bromoterephthalic acid or nitroterephthalic acid.

The mass ratio of the Zr salt to the terephthalic acid or the terephthalic acid substituted by the functional group is 1:1-1: 3.

The carrier resin material is selected from melamine formaldehyde resin, phenolic resin, polyolefin polymer and the like.

The heating reaction temperature is 80-110 ℃, and the heating time is 20-28 hours.

In the metal organic framework foam material, the amount of the metal organic framework loaded on the carrier is 4.4-25.8 wt%.

The invention also provides the metal organic framework foam material prepared by the preparation method.

The invention finally provides the application of the metal organic framework foam material in micro-plastic filtration.

Metal Organic Frameworks (MOFs) are a class of porous crystalline materials assembled from metal ions and organic ligands and have wide applications in gas storage, separation, catalysis, sensing, contaminant filtration, and the like. MOF materials are expected to be able to function in contaminant processing due to their structural tunability, high porosity, rich functionality, various metal centers and tunable functional groups and charges. Thus, MOFs may be potentially functional materials with micro-plastic filtration. However, MOFs have crystalline and brittle properties and are easily powdered, which can hinder their practical use. To solve this problem and explore its potential application in micro-plastic filtration, MOFs must first be processed into materials with intact morphology before they can be widely applied in practical application scenarios. Therefore, the invention provides a method for preparing multifunctional MOF-based foam materials by an acetone-assisted in-situ hydrothermal method. The invention selects the highly stable MOF with strong function, and then processes the MOF into complete materials such as foam and the like to meet the filtration requirement. In the MOF and foam material integrated system, the foam material with porosity can provide an interpenetrating pore structure to ensure that the micro-plastic and the functional MOF are fully contacted, so that in a micro-plastic filtration experiment, higher filtration efficiency is realized to solve the problem of micro-plastic pollution in a water body.

The metal organic framework foam material obtained by the invention keeps original cross interpenetrating pore channels and ductility of foam, ensures that the solvent can fully contact with the material when the solvent rapidly passes through the foam material when the foam material is applied to micro-plastic filtration, thereby realizing effective filtration of the micro-plastic. In addition, the foam material can be applied to micro-plastic filtration with different concentrations and various types, still has good filtration effect, and shows great universality.

The technical effects are as follows: the invention can independently assemble and synthesize various multifunctional foam materials with different functional groups in situ by an acetone-assisted method, and the MOF loading capacity of the foam materials can be regulated and controlled. In particular, these foams have high uniformity, robustness, flexibility, cross-interpenetrating channels and durability, and are easily scaled-up for production. These properties make it well developed for use in filtration of microplastics and in various concentrations and different types of microplastic systems. The combination of MOFs with foams successfully achieved filtration of the microplastics. The method is the first strategy provided aiming at the micro-plastic filtration, and provides effective reference and reference for relieving the problem of micro-plastic pollution in the ocean in the future.

Drawings

FIG. 1 UiO-66-X @ MF (X ═ H, NH) synthesized in examples 1-5 of the invention₂OH, Br and NO₂) Powder X-ray diffraction Pattern (PXRD) of the foam.

FIG. 2 powder X-ray diffraction Pattern (PXRD) for the synthesis of UiO-66-OH @ MF foam material with modulated loading (UiO-66-OH @ MF-n, n ═ 1, 2, 3 and 4) according to inventive example 1.

FIG. 3 UiO-66-X @ MF (X ═ H, NH) synthesized in examples 1-5 of the present invention₂OH, Br and NO₂) Foam structure and morphology characterization pictures: (a) [email protected] MF; (b) UiO-66-NH₂@ MF; (c) UiO-66-OH @ MF; (d) UiO-66-Br @ MF; (e) [email protected] MF; (I) a structural diagram of a supported MOF; (II) MOF-supporting ligands; (III) photographic images of the foam; (IV, V) electronically scanned images of the foam.

FIG. 4 powder X-ray diffraction Pattern (PXRD) of water stability and seawater stability of synthetic UiO-66-OH @ MF foam of inventive example 1: (a) water stability; (b) and (4) seawater stability.

FIG. 5. examples 1-5 of the invention and their adjusted performance efficiency plots for the filtration of the microplastics: (a) foams of different functional groups; (b) different loadings of foam; (c) different types of plastic dispersions; (d) a different number of filter units; (e) plastic dispersions of different molecular weights; (f) plastic dispersions of different concentrations.

Detailed Description