Feasibility of Adsorption Kinetic Models to Study Carrier-Mediated Transport of Heavy Metal Ions in Emulsion Liquid Membranes

Emulsion liquid membranes have been successfully used for the removal of different types of organic and inorganic pollutants by means of carrier-mediated transport mechanisms. However, the models that describe the kinetics and transport of such mechanisms are very complex due to the high number of model parameters. Starting from an analysis of the similarity between the elemental mechanisms of carrier-mediated transport in liquid membranes and of transport in adsorption processes, this paper presents an experimental analysis of the possibility of applying kinetic and mechanistic models developed for adsorption to carrier-mediated transport in emulsion liquid membranes. We study the removal of a target species, in this case, Cu(II), by emulsion liquid membranes containing membrane phase solutions of benzoylacetone (carrier agent), Span 80 (emulsifying agent) and kerosene (diluent), and hydrochloric acid as a stripping agent in the product phase. The experimental results fit the pseudo-second-order adsorption kinetic model, showing good relationships between the experimental and model parameters. Although both Cu(II) diffusion through the feed/membrane interface boundary layer and complex Cu-benzoylacetone diffusion through the membrane phase controls Cu(II) transport, it is the former step that mainly controls the transport process.

An overview on nanostructure-modified supported liquid membranes for the electromembrane extraction method

The efficiency of electromembrane extraction can be improved by modification of supported liquid membrane with various nanomaterials.

Transport and Separation of the Silver Ion with n–decanol Liquid Membranes Based on 10–undecylenic Acid, 10–undecen–1–ol and Magnetic Nanoparticles

This paper presents a transport and recovery of silver ions through bulk liquid membranes based on n–decanol using as carriers 10–undecylenic acid and 10–undecylenyl alcohol. The transport of silver ions across membranes has been studied in the presence of two types of magnetic oxide nanoparticles obtained by the electrochemical method with iron electrodes in the electrolyte with and without silver ions, which act as promoters of turbulence in the membrane. Separation of silver ions by bulk liquid membranes using 10–undecylenic acid and 10–undecylenyl alcohol as carriers were performed by comparison with lead ions. The configuration of the separation module has been specially designed for the chosen separation process. Convective-generating magnetic nanoparticles were characterized in terms of the morphological and structural points of view: scanning electron microscopy (SEM), high-resolution SEM (HR–SEM), energy dispersive spectroscopy analysis (EDAX), Fourier Transform InfraRed (FTIR) spectroscopy, thermal gravimetric analysis (TGA), differential scanning calorimetry and magnetization. The process performance (flux and selectivity) was tested were tested for silver ion transport and separation through n–decanol liquid membranes with selected carriers. Under the conditions of the optimized experimental results (pH = 7 of the source phase, pH = 1 of the receiving phase, flow rate of 30 mL/min for the source phase and 9 mL/min for the receiving phase, 150 rot/min agitation of magnetic nanoparticles) separation efficiencies of silver ions of over 90% were obtained for the transport of undecenoic acid and about 80% for undecylenyl alcohol.

Liquid Membranes in Catalysis

: The supported ionic liquid (SIL) membranes have demonstrated huge potential for numerous applications in current separation science and catalysis. Membrane technology allows for separation of complex mixtures of gases, vapours, liquids and /or solids below trivial conditions. Simultaneous chemical transformations can also be achieved in membranes by using catalytically active materials comprising the membrane or embedded catalysts in the custom built membrane reactors. In the present editorial, the remarkable contribution of liquid membranes in catalysis is highlighted. Some recent applications are presented and compared with conventional methods. In addition, SILs and their applications in catalysis, catalytic membranes and recent advances in membrane separation processes are briefly described.