驱油用Janus片状纳米材料研究现状

Research status of Janus nanosheets for oil displacement

纳米流体驱作为一种新型的低渗透油藏驱油技术,具有注入性好、储层伤害小、驱油能力强、智能响应等优势,越来越受到广泛关注。相比于球形纳米颗粒,Janus片状纳米材料界面自由能低、转动更加受限、可进一步阻止内外相分子扩散并形成界面强度更高的固体颗粒膜,展现出优异的驱油性能。目前,已开发出多种Janus片状纳米材料的制备方法,其在驱油方面的应用主要集中于纳米乳液技术和纳米稳泡技术,此外,智能响应特性同样赋予其更多潜能。当片状纳米材料两面呈现不同的亲油-亲水性时,则同时具有两亲特性和“Pickering”乳液效应,大大提高其作为高效纳米流体驱的能力。随着未来低成本、大规模、绿色环保的可控制备,以及耐温耐盐等性能的进一步提高,应用Janus片状纳米材料有望大幅提高原油采收率,为油田稳产增产带来创新性解决方案。

As a new oil displacement technology for low-permeability reservoirs,nanofluid flooding has advantages such as good injectivity,low formation damage,great displacement ability,and intelligent response,which has attracted more and more attention from researchers. Compared with spherical nanoparticles,Janus nanosheets have lower interfacial free energy and more restricted rotation,which can further prevent the diffusion of internal and external molecules and form solid particle films with higher interfacial strength,exhibiting excellent oil displacement performance. Researchers have developed multiple preparation methods for Janus nanosheets,whose application in oil displacement mainly includes nano-emulsion technology and nano-foam stabilization technology. In addition,the characteristic of intelligent response gives such materials more potential. When one side of the sheet nanomaterials is hydrophilic while the other is hydrophobic,they will show amphipathicity and a“Pickering”emulsion effect simultaneously,which greatly improves their ability as an efficient nanofluid flooding. With low-cost,large-scale,green,and controllable preparation and the improvement in temperature and salt resistance in the future,Janus nanosheets are expected to significantly enhance oil recovery and provide innovative solutions for stable production and stimulation of oilfields.