Utilizing Low-Voltage Pulsed Electric Fields for Mass Transfer Intensification of Drops in Liquid–Liquid Extraction

Abstract

Low-voltage pulsed electric fields, corresponding to field strengths of 2–16 V/cm, were utilized for mass transfer intensification of drops in a liquid–liquid extraction process. The chemical system of kerosene–acetic acid–water was used in which mass transfer resistance lies mainly in the kerosene phase. The applied frequencies were within 100–1000 Hz. In a hydrodynamic study, the circulating state of drops was confirmed based on different criteria and their terminal velocity precisely followed the Grace model. A mass transfer study of drops, on the other hand, revealed the strong impact of a pulsed electric field with the average and maximum enhancements of 30.3 and 70.5%. This can be attributed to the interfacial instability due to switching poles in the pulsed electric field. An optimum frequency of about 300 Hz corresponded to the applied voltages. Applying a direct electric field also had desired effects but in a lower extent. The provided mass transfer coefficient data were reproduced based on the Kumar and Hartland correlation together with a developed correlation of the enhancement factor in terms of dimensionless field strength, frequency, and the drops’ Reynolds number. The maximum deviation between experimental and predicted Sherwood numbers was ±5%.

Mass transfer intensification for carbon quantum dot nanofluid drops under pulsed electric fields

“…As expected, relatively low mass transfer coefficient was relevant when internal turbulence with drop size was the only effective parameter for the base fluid drops, giving values within (118.4–161.7) μm/s. It is while, applying pulsed electric field gives rise the non-uniform distribution of interface accumulated charges and subsequent interfacial instability of drops 26 , leading to values of (172.3–275.1) μm/s. As was pointed, utilizing nanofluids with the responsible mechanism of the Brownian motion is likely.…”

“…6 cm above the tip of nozzles. The details of designed set-up have been previously reported 26 . Each experimental run was repeated at least three times and maximum deviation from average measured concentration values was less than 0.3%.…”

Liquid–Liquid Equilibrium Study of the Ternary Systems (Water + Propionic or Butyric Acids + Kerosene) at T = (293.2, 303.2, and 313.2) K and Ambient Pressure

“…For example, Rathindranath et al used kerosene to extract PA at 303.2 K, 50 while Saien and Jafari employed kerosene to extract acetic acid at three different temperatures: 293.2, 298.2, and 308.2 K. 51 In recent years, kerosene has also been employed as an extracting solvent for other components. 52,53 Stephenson conducted experiments to determine the mutual solubilities of water and various organic compounds, while Amani et al developed a correlation specifically for the water solubility of hydrocarbons. Both studies found that the solubility of water in the organic layer increases with temperature, but for kerosene, it remains below 0.001.…”

“…For example, Rathindranath et al used kerosene to extract PA at 303.2 K, while Saien and Jafari employed kerosene to extract acetic acid at three different temperatures: 293.2, 298.2, and 308.2 K . In recent years, kerosene has also been employed as an extracting solvent for other components. , …”