Research progress on preparation of 2D vermiculite nanosheets and their environmental adsorption of pollutants
Vermiculite(Vrm)is a layered silicate mineral with unique physical and chemical properties such as layered structure,interlayer ion exchangeability,large specific surface area,and nano-layer interlayer space.It is widely distributed,abundant in reserves and low in price.Vrm is thus a good environmental adsorbent material for pollutant removal from water bodies.Due to the stacking of vermiculite flake layers,the huge internal specific surface is difficult to be exposed,which lim-its its adsorption capacity for pollutants.Exfoliating natural vermiculite into two-dimensional nanoflakes with nanoscale thickness is an effective way to obtain the huge internal specific surface area and improve its adsorption performance.In this paper,the preparation methods of 2D vermiculite nanosheets in recent years were reviewed,including thermal expansion ex-foliating pretreatment method,physical exfoliating method,chemical exfoliating method,and combined physical-chemical exfoliating technology,and the advantages and disadvantages of these methods were summarized and compared.The re-search progress on the adsorption properties of exfoliated vermiculite to some water pollutants was briefly described.The pur-pose of this paper was to provide ideas for seeking the high yield exfoliating method of vermiculite and the high value-added application of exfoliated vermiculite in environmental adsorption.Finally,the development trend of 2D vermiculite materials was prospected.
万方数据
维普
