Tailoring of filtration matrix design in dielectrophoretic filtration: towards selective separation for industrial tasks

Abstract

Selective separation and recovery of micro and sub-micro particles is a challenging task for many industries. Among the others techniques to tackle this task, Dielectrophoretic (DEP) filtration established itself for the particle manipulation. While being present for mostly biomedical fields, DEP separators can also be applied towards non-biological particles, such as the ones which come from the electronics scrap. Dielectrophoresis operates in the inhomogeneous electric field and moves polarizable particles, depending on their specific properties. Examples of these properties can be the size of these particles, their shape or material. Dielectrophoretic filtration is based on the generation of this inhomogeneous field with a porous bulk filter and features pressure-driven flow. In previous works on this topic, it was already shown that the separation efficiency of the system would mainly depend on three different clusters of factors. One of the factors is related to the filter itself and its parameters, such as structural or material ones. They were studied in detail in the microfluidic context, however, a clear link to the bulk filters in the context of dielectrophoretic filtration was not established yet. This thesis performed experimental research on modification of the filter matrix. It aimed to connect the separation efficiencies of different types of the packed bed filters to the grain morphology of these packed bed filters. Additionally, the goal was to expand an application scope of the DEP towards non-biological filtration tasks, and separate the type of particles which resemble the ones that come from battery recycling slurry.