Eur. Phys. J. E (2011) 34: 36
https://doi.org/10.1140/epje/i2011-11036-5

Aggregation and disaggregation dynamics of sedimented and charged superparamagnetic micro-particles in water suspension

¹ Dep. Física de Materiales, UNED, Senda del Rey 9, 28040, Madrid, Spain
² Dep. Ciencia y Tec. Apl. I.T. Agrícola, E.U.I.T. Agrícolas, 28040, Madrid, Spain
³ Dep. Física Fundamental, UNED, Senda del Rey 9, 28040, Madrid, Spain

^* e-mail: pdominguez@fisfun.uned.es

Received: 1 August 2010
Accepted: 7 March 2011
Published online: 11 April 2011

Abstract

This article presents results on the aggregation and disaggregation kinetics on a 1μm diameter charged superparamagnetic particles dispersed in water under a constant uniaxial magnetic field in experiments with salt (KCl) added to the suspension in order to observe the behaviour of the system when the electrical properties of the particles have been screened. These particles have an electric charge and are confined between two separated 100μm thick quartz windows, and sediment near the charged bottom wall. The electrostatic interactions that take place in this experimental setup may affect the micro-structure and colloidal stability of the suspension and thus, the dynamics of aggregation and disaggregation.