Skip to Main content Skip to Navigation

Floculation magnétiquement assistée appliquée au traitement des eaux : étude d’un système modèle argile/NP de maghémite

Abstract : Issues related to the increasing pollution of water resources have become a major societal issue that has led researchers and industrialists to focus on developing new, more efficient and faster water treatment processes. One of the key steps in water treatment is flocculation: it is a physic-chemical process during which colloidal particles to be removed (bacteria, natural organic matter, clays...) will agglomerate to form larger particles called flocs. This step is triggered by the addition of a flocculant generally positively charged (aluminum salts, polyelectrolytes...) which will reduce the electrostatic repulsion forces between negatively charged colloidal particles, and cause their aggregation. The problems inherent in this technique are that flocculation and especially settling times are very slow. To solve this problem, we propose the use of a particular flocculant based on magnetic nanoparticles. The addition of this constituent will lead to the production of flocs with high magnetic susceptibility which can then settle very quickly in the presence of a magnetic field gradient resulting from the use of a magnet or an electromagnet... Our work focuses on the study of a model system composed of purified and sized natural beidellite clays of natural origin, playing the role of the pollutant to be eliminated, and magnetic maghemite nanoparticles that play the role of the flocculating agent. The flocs obtained are then left to settle under a gradient of magnetic field obtained with a Nd-Fe-B magnet, or under gravity [...]
Complete list of metadatas

Cited literature [166 references]  Display  Hide  Download
Contributor : Abes Star :  Contact
Submitted on : Thursday, June 11, 2020 - 12:00:54 PM
Last modification on : Wednesday, October 14, 2020 - 3:46:37 AM


Version validated by the jury (STAR)


  • HAL Id : tel-02864757, version 1


Sofia Housni. Floculation magnétiquement assistée appliquée au traitement des eaux : étude d’un système modèle argile/NP de maghémite. Chimie théorique et/ou physique. Sorbonne Université, 2018. Français. ⟨NNT : 2018SORUS334⟩. ⟨tel-02864757⟩



Record views


Files downloads