Flocculation and magnetically-assisted sedimentation of size-sorted beidellite platelets mixed with maghemite nanoparticles  

作　　者：Sofia Housni Sébastien Abramson Jean-Michel Guigner Pierre Levitz Laurent Michot 

机构地区：[1]Laboratoire de PHysico-chimie des Electrolytes et Nanosystèmes InterfaciauX(PHENIX UMR 8234,Sorbonne Université-CNRS),Sorbonne Université,Paris,75252,France [2]Institut de Minéralogie,de Physique des Matériaux et de Cosmochimie(IMPMC UMR 7590,Sorbonne Université-IRD-CNRS-MNHN),Sorbonne Université,Paris,75252,France

出　　处：《Nano Research》2020年第11期3001-3011,共11页纳米研究（英文版）

基　　金：We wish to kindly thank Delphine Talbot and Aude Michel for their technical support,and Cedric Boissiere for the fruitful discussions.We equally acknowledge the local staffs of the ID02 and BM26 lines of the European Scientific Radiation Facility(ESRF)in Grenoble.

摘　　要：In this study,the flocculation and the subsequent decantation step of mixed suspensions of 10 nm-sizedγ-Fe_(2)O_(3) magnetic nanoparticles and 500 nm-sized beidellite clay platelets was investigated.This work may find application in the field of water treatment,specifically the flocculation processes with magnetically assisted sedimentation.After a short description of the preparation and characterization of the raw materials(nanoparticles and clays),the influence of several parameters(pH,concentrations of nanoparticles and clays etc.)on the amount of flocculated materials was examined,which gave information on the concentration ranges allowing a complete flocculation,together with a better understanding on the interactions between nanoparticles and clays responsible for flocculation.The optimal conditions for magnetically assisted settling were then determined by comparing for each sample sedimentation velocities under gravity and in the presence of a Nd-Fe-B magnet.Finally,the complex multiscale structure of the flocs in water was explored,through the measurement of several bulk properties(zeta-potential and volume measurements,laser granulometry),while the organization of the materials at a microscopic scale was investigated by cryo-transmission electron microscopy(cryo-TEM)and small-angle X-ray scattering(SAXS).

关 键 词：magnetic separation nanoparticles clay FLOCCULATION DECANTATION characterization 

分 类 号：TB383[一般工业技术—材料科学与工程]