Graphene, a two-dimensional (2D) carbon nanomaterial, has attracted worldwide attention owing to its fascinating properties. One of critical bottlenecks on some important classes of applications, such as printed electronics, conductive coatings, and composite fillers, is the lack of industrial-scale methods to produce high-quality graphene in the form of liquid suspensions, inks, or dispersions. Since 2008, when liquid-phase exfoliation (LPE) of graphene via sonication was initiated, huge progress has been made in the past decade. This review highlights the latest progress on the successful preparation of graphene in various media, including organic solvents, ionic liquids, water/polymer or surfactant solutions, and some other green dispersants. The techniques of LPE, namely sonication, high-shear mixing, and microfluidization are reviewed subsequently. Moreover, several typical devices of high-shear mixing and exfoliation mechanisms are introduced in detail. Finally, we give perspectives on future research directions for the development of green exfoliation media and efficient techniques for producing high-quality graphene. This systematic exploratory study of LPE will potentially pave the way for the scalable production of graphene, which can be also applied to produce other 2D layered materials, such as BN, MoS2, WS2, etc.

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a b s t r a c tThis study developed a novel mobile industrial-scale fluidized adsorption process and preliminarily explored its application in the emergency water treatment. A lab-based Liquid-Solid Circulating Fluidized Bed (LSCFB) was prepared and the flow pattern was studied by validated computational fluid dynamics (CFD) models. The simulation results revealed that the particular uneven flow structure, which could weaken aniline removal performance, occurred with increasing superficial liquid velocity. Accordingly, an optimized distributor design was constructed by the established CFD models; notably, the effect of open angles on the flow pattern, which was often overlooked by previous studies, was mainly discussed. Then, the aniline removal efficiency of LSCFB pre and post optimization was compared. The experimental results demonstrate that dynamic adsorption capacity on aniline reached 70 mg/g under the optimum conditions (initial aniline concentration of 100 mg/L, superficial liquid velocity of 3u mf and sorbent dosage of 27 g/L). By comparison with fixed-bed adsorption, the LSCFB possessed significantly higher adsorption rate constants and shorter hydraulic retention time, which indicates that LSCFB could meet emergency treatment requirements in a better way. Finally, the study developed the mobile industrial-scale fluidized adsorption process and estimated process parameters for aniline removal in the Sudden Water Pollution Accident of Zhuozhang River.

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