A new concept of an electrostatic spray column for liquid-liquid extraction was investigated. An important problem for separation processes is the presence of azeotropic or close-boiling mixtures in their production, for example heptane with ethanol, since the separation is impossible by ordinary distillation. The use of ionic liquids (IL) as a dispersed solvent specially engineered for any specific organic mixture in terms of selectivity is a key factor to successful separation. As IL present particularly attractive combination of favorable characteristics for the separation of heptane and ethanol, in this work we use 1-butyl-3-methylimidazolium methyl sulfate [BMIM][MeSO4]. Because of high viscosity and relatively high cost of IL a new technique was introduced, consisting in the electrostatically spray generation to enhance the mass transport between the phases. In order to optimally design the geometry of the contactor a series of numerical simulation was performed. Especially multi-nozzle variants for better exploitation of contactor volume were investigated. Experiments showed excellent possibility of control of the dispersion characteristics by applied voltage and thus control of the rate of extraction. The preliminary simulations based on our mathematical model for a three nozzle variant exhibited visual agreement with the theory of electrostatics.

Liquid-liquid extraction provides an environmentally friendly process as an alternative to azeotropic distillation, pervaporation and reverse osmosis because these techniques require the use of large amounts of energy, may involve volatile organic compounds, and operation at high pressure.

Ionic liquids (ILs) continue to gain wide recognition as potential environmentally friendly solvents due to their unique properties. However due to their current high cost, their use in industry is seriously limited without an efficient methodology for recovery and recycle.

In this paper we describe an innovative methodology for a liquid-liquid extraction process based on an electrically induced emulsion of an ionic liquid as the extracting solvent dispersed in an organic mixture. This offers a most efficient exploitation of the solvent. On the other hand we present our own design of a pilot (semi-industrial) scale extractor based on this methodology and which demonstrates effective recovery of the ionic liquid. In order to achieve this goal we used a numerical modelling tool implemented using our own simulation software based on the finite element method. We also used our original previous experience with generating and investigating liquid-liquid electrosprays using phase Doppler anemometry. Finally we present recommendations for contactor geometry and for the preferred operating conditions for the extractor.

In this article, we present the results of the first application of 2–benzoylpyridine (2–BP) as a carrier in adsorptive polymeric materials dedicated for the removal of Ag(I) and Cu(II) ions from model acidic solutions. In the first stage of the research, the classical solvent extraction, in which 2–BP was used as an extractant, allowed to determine the proper conditions for conducting adsorptive processes. The stability constants of 2–BP complexes with analyzed metal ions were determined using the spectrophotometric method. The electrospray ionization (ESI) high-resolution mass spectrometry (HRMS) method was applied for the confirmation of the ability of 2–BP molecules to form complexes with Cu ²⁺¸ metal ions in a solution and to determine the elemental composition of generated complexes (to identify the ratio of the number of metal ions to the number of molecules of 2–BP). The obtained results indicate that both the adsorptive processes and solvent extraction strongly depend on the properties of metal ions and that the use of 2–BP as a carrier/extractant allows for efficient removal of silver(I) ions and much less effective removal of copper(II) ions. The utilization of adsorptive polymeric materials is in line with the contemporary research trends that focus on eco-friendly and cost-effective methods.