Trapping heavy metals by using calcium hydroxyapatite and dielectrophoresis

John Batton (1) , Arun John Kadaksham (1) , Ange Nzihou (2) , Pushpendra Singh (1) , Nadine Aubry (1)

1 Department of Mechanical Engineering
2 RAPSODEE - Centre de recherche d'Albi en génie des procédés des solides divisés, de l'énergie et de l'environnement

We propose a novel technique for the removal of heavy metal waste from contaminated water. Our method consists in using dielectrophoresis (DEP) to trap hydroxyapatite (HAP) particles of 1 mu m size in water after they have adsorbed heavy metal (Pb, Zn, Cu, Co and Cr). Although HAP can adsorb heavy metals in water and as such offers great promise as a waste-cleaning tool [1-3], one of the current challenges is the elficient removal of the HAP particles once they have adsorbed the heavy metals. We show in this paper that DEP can be used to concentrate such particles in certain regions, thus rendering the rest of the solution volume nearly free of contaminated particles. We present here both experimental and numerical results for suspensions at low concentrations.

Mots clés: microfluidics; MEMS; removal of heavy metals; waste water filtration; dielectrophoresis (DEP); calcium hydroxyapatite (HAP); Dielectrophoresis (DEP); Calcium hydroxyapatite (HAP); Waste water filtration; Removal of heavy metals; Microfluidics

Domaines: Génie chimique; Ingénierie de l'environnement

John Batton, Arun John Kadaksham, Ange Nzihou, Pushpendra Singh, Nadine Aubry. Trapping heavy metals by using calcium hydroxyapatite and dielectrophoresis. Journal of Hazardous Materials, 2007, First International Conference on Engineering for Waste Treatment: Beneficial Use of Waste and By-Products (WasteEng2005), 139 (3), pp.461-466. ⟨10.1016/j.jhazmat.2006.02.057⟩. ⟨hal-01634393⟩