阅读说明：本技术 一种交联聚乙烯亚胺的mof膜及其制备方法 (A kind of MOF film of crosslinked polyethylenimine and preparation method thereof ) 是由 刘福强 张艳红 冯悦峰 袁冉冉 向启 李爱民 于 2019-09-06 设计创作，主要内容包括：本发明公开了一种交联聚乙烯亚胺的MOF膜及其制备方法,将MOF膜与聚乙烯亚胺在交联剂的作用下,在溶液中进行交联反应得到PEI/MOF膜；本发明利用沉积法制备的MOF膜表面交联聚乙烯亚胺聚合物,同步提升了MOF膜稳定性及膜通量；本发明所述及的利用聚乙烯亚胺同步提升MOF膜稳定性及膜通量的方法,工艺简单、操作简便,在膜处理重金属方向具有广泛的应用价值。(The invention discloses MOF films of a kind of crosslinked polyethylenimine and preparation method thereof, by MOF film and polyethyleneimine under the action of crosslinking agent, carry out cross-linking reaction in the solution and obtain PEI/MOF film；The present invention utilizes the MOF film surface crosslinked polyethylenimine polymer of sedimentation preparation, Synchronous lifting MOF membrane stability and membrane flux；It is of the present invention and the method using polyethyleneimine Synchronous lifting MOF membrane stability and membrane flux, it is simple process, easy to operate, be with a wide range of applications in film process heavy metal direction.)

1. a kind of MOF film of crosslinked polyethylenimine, which is characterized in that by MOF film and polyethyleneimine crosslinking agent effect Under, cross-linking reaction is carried out in the solution obtains PEI/MOF film.

2. the MOF film of crosslinked polyethylenimine according to claim 1, which is characterized in that MOF in the MOF film Any one of metal in Zn, Cu, Co, Fe, Zr or Al, the organic ligand are 2- amino terephthalic acid (TPA) or 2- first Any one in base imidazoles.

3. a kind of preparation method of the MOF film of crosslinked polyethylenimine, which is characterized in that it is described the preparation method is as follows:

1) mixed solution of polyethyleneimine and crosslinking agent is configured；

2) mixed solution is carried on to MOF film surface by way of filtering or impregnating；

3) it carries out cross-linking reaction and obtains PEI-MOF film.

4. the preparation method of the MOF film of crosslinked polyethylenimine according to claim 3, which is characterized in that described is mixed The mass concentration for closing polyethyleneimine in solution is 0.1~10.0%.

5. the preparation method of the MOF film of crosslinked polyethylenimine according to claim 3, which is characterized in that the friendship Joining agent is epoxychloropropane or glutaraldehyde, and the mass concentration of crosslinking agent is 0.01~5.0% in mixed solution.

6. the preparation method of the MOF film of crosslinked polyethylenimine according to claim 3, which is characterized in that the step It is rapid 2) in dip time be 0.5~for 24 hours.

7. the preparation method of the MOF film of crosslinked polyethylenimine according to claim 3, which is characterized in that the step It is rapid 3) in crosslinking temperature be 40~80 DEG C, crosslinking time be 0.5~5h.

8. a kind of MOF film of crosslinked polyethylenimine as described in claim 1 is in the heavy metal zwitterion contaminant water containing murder by poisoning Application in the improvement of body, the heavy metal zwitterion are the zwitterion of Cu, Pb, Cd, Zn, Ni, Cr, As, As and Cr.

Technical field

The present invention relates to the MOF film of environmentally conscious materials preparation and application field more particularly to a kind of crosslinked polyethylenimine and Preparation method.

Background technique

It is widely present in industrial wastewater, surface water and groundwater and poisons metal cation and anion, to water quality safety It constitutes a serious threat with ecological environment.Common heavy metal pollution of water body cut down technology include chemical precipitation method, ion-exchange, Absorption method and membrane separation process etc., chemical precipitation method need to add a large amount of medicaments, and operating cost is high, secondary pollution weight；Ion exchange Method antifouling property is poor, and processing cost is high；Absorption method consumes a large amount of adsorbents, it is difficult to scale application；And membrane separation process has Separative efficiency is high, the rate of departure is fast, equipment is simple, the advantages that being easily recycled, and receives much attention in recent years in water treatment field, but There are the anti-fouling performances of film it is poor, cost of investment is high the deficiencies of.

Domestic and foreign literature investigation display, the conventional adsorbed film that chelates can only remove single heavy metal cation or anion, It for the system that complicated zwitterion coexists, needs for different films to be combined, this will undoubtedly increase operation complexity and operation Cost.Metal organic frame polymer (MOF) is a kind of novel porous coordination polymer material, high with specific surface area, The advantages such as more, the crystalline structure easy-regulating of active site, are widely used in energy storage and environmental improvement.It is controlled in water environment pollution Reason aspect, the surface the nitrogenous class MOF functional group abundant not being coordinated can be complexed with heavy metal cation, while under mild acid conditions Nitrogen-containing functional group protonation can have good by electrostatic force combination heavy metal anion in Heavy Metal Pollution Control Good application prospect, but its water stability limits the application in terms of water pollution control, therefore it is poly- to improve metal organic frame Closing stability of the object in water body is to greatly develop the key technology of the novel environment functional material.

Present load is to improve the common method of MOF stability, and MOF is carried in functionalization basis material, can both be sent out It waves MOF to act on the removal of target contaminant, and the functionalization that can promote basis material acts on the reality, it can be achieved that MOF material Using.Film is the beneficial carrier of MOF, is current research heat by MOF by way of doping or area load in conjunction with film Point.

The patent of China Patent No. CN201510406203 discloses a kind of metal organic framework for gas separation The preparation method of ZIF-9, by the α-Al of modified₂O₃Carrier impregnation passes through heating, constant temperature and cooling three into ZIF-9 mother liquor A process obtains ZIF-9 film, and the ZIF-9 film of acquisition has structure continuous, uniformly, fine and close, but preparation process step is many and diverse, difficult With application, preparation process is difficult to the load capacity that quantification is precisely controlled MOF.

China Patent No. CN201810039919.X discloses a kind of metal organic framework composite ultrafiltration membrane material and its system Standby and application, discloses a kind of infusion process original position carried metal organic backbone coordination polymer, metal organic framework and film matrix PVDF is by hydroxy combining, and the preparation method is simple, but is difficult to ensure the Load Balanced of MOF, and the stability of film is poor.Li et al. People (Water Res.2018,143,87-98.), in pvdf membrane area load ZIF-8 nano particle, is gone forward side by side by way of filtering In a manner of in-situ polymerization acrylic acid, by particle immobilization, MOF stable structure is made in one step, but because MOF deposition causes under flux The problem of drop, is not improved preferably.

Therefore, it there is an urgent need to research and develop a kind of method for being effectively improved the loss of MOF film nano particle, and can solve because MOF is negative The decline problem of membrane flux caused by carrying guarantees that MOF film still has high throughput in continuous service, to meet actual application Demand.

Summary of the invention

For the problem that above-mentioned MOF membrane flux is low, stability is poor, it is an object of that present invention to provide a kind of using poly- The MOF film of the method, in particular to a kind of crosslinked polyethylenimine of aziridine Synchronous lifting MOF membrane stability and membrane flux and Preparation method.

In order to achieve the above object, The technical solution adopted by the invention is as follows: a kind of MOF film of crosslinked polyethylenimine, By MOF film and polyethyleneimine under the action of crosslinking agent, cross-linking reaction is carried out in the solution and obtains PEI/MOF film.

Any one of the metal of MOF in Zn, Cu, Co, Fe, Zr or Al, described in the MOF film referred in the present invention Organic ligand be any one in 2- amino terephthalic acid (TPA) or 2-methylimidazole.

It is described the preparation method is as follows: 1) the invention discloses a kind of preparation method of the MOF film of crosslinked polyethylenimine Configure the mixed solution of polyethyleneimine and crosslinking agent；2) mixed solution is carried on to MOF film by way of filtering or impregnating Surface；3) it carries out cross-linking reaction and obtains PEI-MOF film.

The mass concentration of polyethyleneimine is 0.1~10.0% in mixed solution of the invention；By in the concentration range Polyethyleneimine, can effectively fix the MOF of film surface, and do not influence on the fenestra of MOF film.

Crosslinking agent of the invention is epoxychloropropane or glutaraldehyde, in mixed solution the mass concentration of crosslinking agent be 0.01~ 5.0%；The connectivity that can further improve polyethyleneimine amine molecule by certain density crosslinking agent forms it into netted big point Son promotes intensity and curing performance.

In preparation method of the invention dip time be 0.5~for 24 hours；Pass through the effective dip time in the time range It ensure that polyethyleneimine in the deposition of MOF film fenestra and surface.

Crosslinking temperature is 40~80 DEG C in preparation method of the invention, and crosslinking time is 0.5~5h；In suitable crosslinking temperature Degree and time ensure that crosslinking validity, and excessively high crosslinking temperature has an adverse effect to the stability of film.

A kind of MOF film of crosslinked polyethylenimine answering in the improvement of the heavy metal zwitterion polluted-water containing murder by poisoning With the heavy metal zwitterion is the zwitterion of Cu, Pb, Cd, Zn, Ni, Cr, As, As and Cr.

The present invention has the advantages that 1) present invention provides a kind of method using the surface-crosslinked fixation of polyethyleneimine, together The method that step improves MOF film pure water flux and stability makes full use of the hydrophilicity of polyethyleneimine and good polymerization to hand over Join characteristic, forms multichain reticular structure in MOF film surface, and can penetrate into MOF membrane pores, combine closely, play therewith The effect of immobilization MOF improves the stability of MOF film.

2) amino abundant has good hydrophilicity in polyethyleneimine amine structure, improves MOF film because MOF particle is stifled The problem of flux caused by fenestra declines is filled in, it can be by the flux recovery of MOF film to the level of commercial ultrafiltration membrane.

3) polyethyleneimine amido functional group abundant has complexing to heavy metal cation, increases in practical application Strong retention removal ability of the MOF to heavy metal.

4) pure water flux of MOF film is 300~500L/ (m in the prior art²H), PEI/MOF film of the invention Pure water flux is 700~900L/ (m²·h)。

5) solution containing heavy metal was subjected to film experiment, and tested the heavy metal concentration in efflux, crossing film rate can Up to 5~50L/ (m²H), the rejection of heavy metal is up to 94.1% or more.

6) it is 3000L/m that the PEI/MOF film described in crosses film experiment it is reachable that volume is effectively treated in heavy metal²When, MOF's lets out Leakage quantity is lower than 0.01mg/L.

Detailed description of the invention

Fig. 1 is that the SEM figure of film surface and the section SEM of film scheme.

Wherein (a), (b), (c) be film surface, (d), (e), (f) be film section；

(a) it is PVDF, (b) is [email protected], (c) be PEI/[email protected], (d) be PVDF, (e) is Zr- [email protected] (f) is PEI/[email protected]

Fig. 2 is PVDF, the ATR-FTIR of [email protected] and PEI/[email protected] schemes；

Fig. 3 is the XRD diagram of PVDF, [email protected] and PEI/[email protected]；

Fig. 4 is the result figure of the leakage rate of Zr in [email protected] and PEI/[email protected] operational process；

Fig. 5 is the logical of Zr-MOF/PVDF, PVA/Zr-MOF/PVDF, PAA/Zr-MOF/PVDF and PEI/Zr-MOF/PVDF Measure comparison diagram；

Fig. 6 is removal effect figure of the Zr-MOF/PVDF and PEI/Zr-MOF/PVDF composite membrane to different heavy metals.

Fig. 7 is dynamic removal effect figure of the Zr-MOF/PVDF and PEI/Zr-MOF/PVDF composite membrane to Cr (VI)；

Fig. 8 is dynamic removal effect figure of the Zr-MOF/PVDF and PEI/Zr-MOF/PVDF composite membrane to Cr (III)；

Wherein, Cr (VI) refers to that the Cr ion of 6 valence states, Cr (III) refer to the Cr ion of trivalent state.

Specific embodiment

The present invention is described in further detail with specific embodiment for explanation with reference to the accompanying drawing.

English as mentioned in the embodiments of the present invention is write a Chinese character in simplified form, and specific Chinese meaning is as follows:

PVDF: Kynoar；

The pvdf membrane of [email protected]:Zr system MOF；

PEI/[email protected]: it is crosslinked the pvdf membrane of the Zr system MOF of PEI；

PVA/Zr-MOF/PVDF: the pvdf membrane of the Zr system MOF of cross-linking polyvinyl alcohol (PVA)；

PAA/Zr-MOF/PVDF: the pvdf membrane of the Zr system MOF of polymeric polymer propene acid (PAA)；

ATR-FTIR: decaying In situ ATR-FTIR；

XRD:X x ray diffraction；

PAN；Polyacrylonitrile；

PES: polyether sulfone；

PS: polysulfones；

PEI: polyethyleneimine；

SEM: scanning electron microscope；