Novel RGO/MXene composite film and preparation method thereof

Abstract

The invention discloses a novel RGO / MXene composite film and a preparation method thereof, and the method comprises the following steps: carrying out reduction processing on GO through DA to prepare RGO; stripping MAX by using a LiF and HCl mixed solution to obtain a two-dimensional MXene material with a clear lamellar structure; ultrasonically mixing an MXene dispersion solution and an RGO dispersion solution, constructing the RGO / MXene composite film on a PVDF film substrate in a vacuum filtration manner, and applying the RGO / MXene composite film to processing of industrial wastewater. According to the method, the synergistic film-forming mechanism and the separation mechanism of the RGO and the MXene are explored in detail, and some reference significance is provided for further widening the application range of the MXene and developing and constructing more novel high-performance film materials. From the perspective of improvement of the structure of the film material, the processing efficiency and the recyclability of the film are improved, and finally the practical purpose of reducing the industrial wastewater processing cost is achieved.

Description

technical field [0001] The invention relates to the field of material technology, in particular to a preparation method of a novel RGO / MXene composite membrane and a novel RGO / MXene composite membrane prepared by the method. Background technique [0002] Industrial wastewater refers to the wastewater and waste liquid produced in the process of industrial production. Its pollutants are various and complex (common such as oil, dyes, heavy metals and microorganisms, etc.). If they are not treated effectively before discharge, the surrounding ecological environment will and human health constitute a huge threat. Membrane separation technology has the characteristics of high separation efficiency and environmental friendliness. It has been widely used in industrial wastewater treatment and other fields, and has the reputation of "21st century water treatment technology". Membrane material is the key to membrane separation technology and the core component of membrane technology ...

AI Technical Summary

Problems solved by technology

[0005] However, the above-mentioned process has the following disadvantages: ① directly filter the reduced graphene oxide (RGO) on the surface of the membrane, it is impossible to determine whether the membrane stack is uniform, and the change of the interlayer distance between RGO and GO cannot be quantitatively judged through characterization or theoretical calculation. Realize the precise construction and directional regulation of the membrane

② With the expansion of the interlayer spacing after dopamine modification, the risk of RGO detachment on the support layer CA membrane is increased, so the mechanical properties of the final PDA-RGO composite membrane will be reduced

In the actual process, the membrane will be repeatedly impacted by the liquid to be separated, resulting in the destruction of the final membrane structure, shortening the service life of the membrane, and increasing the separation cost

③The cellulose acetate membrane (CA) material itself is not resistant to acid and alkali, and its mechanical properties are also poor. Therefore, the PDA-RGO composite membrane constructed with the cellulose acetate (CA) membrane as the support layer is suitable for high acid-base, high temperature or high-salt wastewater processing, basically has no practical application value

This technology shows that the most suitable MXene content is 0.2g, which obviously leads to too thick MXene separation layer, and it is impossible to determine the separation mechanism of MXene for the separation of pollutant molecules in water

③The functional groups on the surface of MXene itself are relatively simple, and the performance of the pure MXene / PES composite membrane needs to be further improved. For example, the rejection rate of the composite membrane for salt ions is very low, only about 10%, so it is necessary to micro-control the MXene

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