The Effect of Nanoparticles on Liquid Holdups in a Randomly Packed Liquid-Liquid Extraction Column

Abstract

In the present study, the dispersed phase holdup was measured in a randomly packed column filled with stainless steel Raschig ring packings using water-toluene chemical system. Based on holdup data, the results were analyzed with the aim of determining the influence of dispersed phase flow rate and drop diameter in the presence and absence of silica nanoparticles with particle sizes of 10, 30, and 80 nm and concentrations of 0.01, 0.05, and 0.1 vol%. The results indicate that liquid holdups increase with increase in dispersed phase flow rate. The presence of the nanoparticles influence in both static and dynamic holdups. The experimental results showed that increasing nanoparticle content in dispersed phase increases the dynamic holdup while static holdup decreases. However, by increasing the size of nanoparticles the dynamic and static holdup also follow a similar trend. Finally a successful correlation is proposed for total liquid holdup, which yielded an average error of 6% and shows a good agreement between predicted and experimental results. This is for the first time that a correlation is proposed to estimate total liquid holdup as a function of nanoparticle size and concentration in liquid-liquid extraction systems.