Removing Mn(II) from water using bentonite and dielectrophoresis
利用皂土吸附和介电泳方法间接去除水中的Mn2+

Removal of heavy metals from water is one of the most difficult problems in water treatment. Manganese is one of the indispensable elements for animals, but excessive manganese can be toxic to the nerve system. In our experiments, manganese ions in ultrapure water are firstly adsorbed by bentonite particles. The suspension is then injected to a chamber with a microchip of microelectrode arrays. The bentonite particles which have adsorbed Mn2+ are trapped in stronger electric-field regions after voltage is applied, indicating positive dielectrophoresis. This paper provides an experimental basis for a feasible method to remove heavy metal ions indirectly from waste water, without leading to secondary pollution.