چكيده به لاتين
In recent years, considerable attention has been focused on diclofenac as a group of emerging water contaminants. Therefore, choosing a suitable method for separation of this compound from aquatic environment is very important. Microfluidic solvent extraction can be used for this purpose due to low material consumption, high surface area to volume ratio, short diffusion length and good process control. In this work, liquid-liquid two‐phase flow patterns and extraction of diclofenac from aqueous solution with Tetra-n-butylammonium bromide (TBAB) in microchannel were experimentally studied. The effect of different parameters such as flow rate, flow rate ratio, residence time and channel dimensions on extraction efficiency and volumetric mass transfer coefficient in three different flow pattern including parallel flow, slug flow and droplet flow were investigated. Our experimental results show that at the same flow rate of two phases, an increases in total flow rate changes flow pattern from slug to parallel flow and extraction efficiency decreases. droplet flow was observed at the higher organic to aqueous flow rate ratio of 2.5 and extraction efficiency increased due to increase in specific interfacial area. At the same conditions, parallel and slug flow were compared with each other, and extraction efficiency of slug flow was 10.7% higher than that of parallel flow. At the residence time 19 s, equilibrium efficiency (99.2%) was achieved in slug flow. Volumetric mass transfer coefficient was examined at channel length of 6 cm, 9 cm and 12 cm and width of 400 μm,600 μm and 800 μm. The results demonstrated that microchannel at the length of 9 cm and width of 400 μm has the best mass transfer performance.
