Clogging by sieving in microchannels: Application to the detection of contaminants in colloidal suspensions

TL;DR

This paper introduces a microfluidic technique to detect and quantify large contaminants in colloidal suspensions by analyzing clogging events in microchannels, providing a rapid and versatile characterization method.

Contribution

The study presents a novel microfluidic approach for measuring contaminant concentrations in colloids based on clogging dynamics in microchannels.

Findings

Effective detection of large contaminants through clogging analysis

Quantitative estimation of contaminant concentration

Versatile method applicable to various colloidal suspensions

Abstract

We report on a microfluidic method that allows measurement of a small concentration of large contaminants in suspensions of solid micrometer-scale particles. To perform the measurement, we flow the colloidal suspension through a series of constrictions, i.e. a microchannel of varying cross-section. We show and quantify the role of large contaminants in the formation of clogs at a constriction and the growth of the resulting filter cake. By measuring the time interval between two clogging events in an array of parallel microchannels, we are able to estimate the concentration of contaminants whose size is selected by the geometry of the microfluidic device. This technique for characterizing colloidal suspensions offers a versatile and rapid tool to explore the role of contaminants on the properties of the suspensions.