Metal ion extraction in microheterogeneous systems

International audienc

Rate of Interfacial Reactions Compared to Bulk Reactions in Liquid–Liquid and Micellar Processes: An Attempt to Clarify a Confusing Situation

International audienc

Kinetics and mechanism of biphasic transfer of salted water from an aqueous phase to AOT reverse micelles

International audienceThe transfer of salted water from an external aqueous phase to AOT reverse micelles is studied in relation with the change of properties from a percolating to a non percolating state of the micelles. A membrane-separated two-compartment cell was used to measure the transfer of salt which was followed by conductivity measurements. We expected a sharp conductivity drop which could have been used as a kind of sensor to detect a threshold of salinity. In fact, this sharp drop was not observed and this is shown to be due to the fact that no excess water is incorporated in the microemulsion phase in these conditions. For this purpose separate analysis of the water and salt incorporated in the microemulsion phase versus time has been performed. Under the conditions used the increase of the salt content is accompanied by a decrease of the water content, even though the initial system was far from being saturated with water. The results are discussed in terms of the different possible mechanisms. Molecular diffusion of water appears to be unlikely and its expulsion can be simply explained by the shrinkage of the microdroplets merging with the interfacial film, this being associated with the electrostatic shielding of the polar head repulsions

Kinetics of complexation of lanthanide ions by 3-methyl-4-acyl-5-pyrazolone derivatives in micellar and microemulsion media

International audienc

Preparation and Properties of Vesicles Formed from Phospholipid Analogues of N -(Phosphonoacetyl)- L -aspartate (PALA) by Sonication or Extrusion: Transition Temperature, Particle Size, Glucose Entrapment, and 31 P NMR

International audienc

Copper Extraction Kinetics by Beta-Diketone Derivatives (Acylpyrazolones and Acylisoxazolones) in Water/Chloroform Biphasic System

International audienc

Hydrodemetallation and Hydrodesulfurization Spent Catalysts Elemental Analysis: Comparison of Wavelength Dispersive X-ray Fluorescence and Atomic Emission Spectrometries

International audienc

Preliminary Assays on Electrochemically Modulated Liquid-liquid Extraction of Metformin

International audienc

Electrochemically Modulated Liquid–Liquid Extraction for Sample Enrichment

International audienceA new sample preparation method is proposed for the extraction of pharmaceutical compounds (Metformin, Phenyl biguanide, and Phenformin) of varied hydrophilicity, dissolved in an aqueous sample. When in contact with an organic phase, an interfacial potential is imposed by the presence of an ion, tetramethylammonium (TMA +), common to each phase. The interfacial potential difference drives the transfer of ionic analytes across the interface and allows to reach up to nearly 100 % extraction efficiency and a 60-fold enrichment factor in optimised extraction conditions as it is determined by HPLC analysis.