Influence of quadrupole magnetic field on mass transfer in an extraction column in the presence of MnFe2O4 nanoparticles

Abstract

Recently, it has been observed that the use of magnetic nanoparticles and the magnetic field would result in heat and mass transfer intensification. But most of the investigations have been devoted to the enhancement of heat transfer. However, the investigations on the applicability of magnetic nanoparticles for mass transfer improvement are still in the developing stage. In the present study, the effect of MnFe2O4 nanoparticles on the mass transfer performance of a packed extraction column is evaluated in the presence of constant and alternating magnetic fields. The column is filled with Penta-Pak TM PS-500M1 structured packing; while four identical bar electromagnets made from zinc ferrite cores are used to generate the quadrupole magnetic field. The (toluene-acetic acid)-water system is employed. Spinel-type manganese ferrite nanoparticles are added to the organic dispersed phase (toluene+acetic acid) to intensify solute transfer. The quadrupole magnetic field is applied from 100 to 500G intensity and 100 to 500Hz frequency, accompanied with different nanoparticle concentrations from 0.001wt% to 0.005wt%. According to our observations, mass transfer performance increases remarkably in the presence of magnetic nanoparticles under the influence of magnetic field. Compared with no magnetic field, maximum improvements of 115% and 43% in overall mass transfer coefficient and extraction fraction are observed under alternating magnetic field with 300Hz frequency and 500G intensity for 0.003wt% nanoparticle concentration. That is, by using the magnetic nanoparticles and the magnetic field, one can considerably improve the performance of a liquid-liquid extraction system.