Separation of natural compounds using eutectic solvent-based biphasic systems and centrifugal partition chromatography.

A study on the formation of ternary biphasic systems composed of heptane, 1-butanol or ethyl acetate and type III or type V deep eutectic solvents based on levulinic acid and choline chloride or thymol was carried. Binodal curves and densities and phase compositions of phases in equilibrium for seven systems are reported. The partition coefficients of six natural compounds, namely quercetin, apigenin, coumarin, β-ionone, retinol, and α-tocopherol, in these systems were measured.

Treatment of Pulp Black Liquor with an Ionic Liquid: Modeling and Optimization by Using Response Surface Methodology and Central Composite Design.

In this study, selective extraction towards ionic liquid trihexyltetradecylphosphonium chloride ([P ]Cl) of lignin residues, polysaccharides and organic acids present in black liquor (BL), the main principal wastewater of pulping industry was studied. With the objective of finding optimized conditions allowing to extract lignin residues while polysaccharides and organic acids remain in aqueous solution, a design of experiments approach based on a response surface methodology was used. Three continuous factors, namely initial pH varying from 9 to 13.

Merxm. Essential Oil: Natural Heptane Source and Co-Product Valorization.

As an alternative to fossil volatile hydrocarbon solvents used nowadays in perfumery, investigation on essential oil of Merxm. oleo gum resin as a source of heptane is reported here. Heptane, representing up to 30 wt-% of this oleo gum resin, was successfully isolated from the essential oil, using an innovative double distillation process.

Characterization of Flavor Compounds in Distilled Spirits: Developing a Versatile Analytical Method Suitable for Micro-Distilleries.

Over the last few years, the development of micro-distilleries producing diverse spirits with various flavors has been observed. Versatile analytical techniques for the characterization of aroma compounds in such alcoholic beverages are therefore required. A model mixture embodying a theoretical distilled spirit was made according to the data found in literature to compare usual extraction techniques.

Sustainable extraction of antioxidants from out-of-caliber kiwifruits.

Valorisation of discarded kiwifruits is proposed by extracting bioactive compounds using sustainable solvents namely deep eutectic solvents (DES). A screening of fifteen DES and several hydrogen bonding donor solvents was carried out. Extraction efficiency was measured in terms of antioxidant activity using DPPH and FRAP tests.

Rh(III) Aqueous Speciation with Chloride as a Driver for Its Extraction by Phosphonium Based Ionic Liquids.

In this work, the aqueous speciation of Rh(III) in chloride medium was investigated by UV-vis spectroscopy for ligand to metal ratios R = (Cl)/(Rh) ranging from 300 to 5000, at fixed Rh concentration (2.4 × 10 M). Under the chemical conditions of this work, no time evolution was observed, which allows for the fitting of the UV-vis data by Principal Component Analysis (PCA) and Multi-Curve Resolution (MCR).

Mechanisms of phase separation in temperature-responsive acidic aqueous biphasic systems.

The temperature responsive solubility of ionic liquids with 'bulky' polar regions, such as tributyltetradecyl phosphonium chloride ([P44414]Cl), in acidic aqueous solutions is elucidated through a combined experimental and computational approach. The temperature effect in the acidic aqueous biphasic system HCl/[P44414]Cl/H2O was characterised in the range 273 K to 373 K and was found to significantly deviate from the corresponding aqueous biphasic system with NaCl. A new transferable coarse grained MARTINI model for [P44414]Cl was developed, validated and applied to provide a molecular understanding of the experimental results.

Understanding the fundamentals of acid-induced ionic liquid-based aqueous biphasic system.

Ionic-liquid-based aqueous biphasic systems (IL-based ABS) have demonstrated exceptional performance in bioseparation processes. However, IL-based ABS are of limited interest for metal extraction as most metals are not stable in their neutral or alkaline pH conditions. In the quest for better extraction systems for metals, the development of IL-based ABS with highly acidic solutions (AcABS), induced by the mixture of a hydrophilic IL ([P44414]Cl), a mineral acid (HCl, HNO3 or H2SO4) and water, opens new possibilities.

Mechanism of ionic-liquid-based acidic aqueous biphasic system formation.

Ionic-liquid-based acidic aqueous biphasic systems (IL-based AcABS) represent a promising alternative to the solvent extraction process for the recovery of critical metals, in which the substitution of the inorganic salt by an acid allows for a 'one-pot' approach to the leaching and separation of metals. However, a more fundamental understanding of AcABS formation remains wanting. In this work, the formation mechanisms of AcABS are elucidated through a comparison with traditional aqueous biphasic systems (ABS).

Ionic-Liquid-Based Acidic Aqueous Biphasic Systems for Simultaneous Leaching and Extraction of Metallic Ions.

The first instance of an acidic aqueous biphasic system (AcABS) based on tributyltetradecyl phosphonium chloride ([P ][Cl]) and an acid is here reported. This AcABS exhibits pronounced thermomorphic behavior and is shown to be applicable to the extraction of metal ions from concentrated acidic solutions. Metal ions such as cobalt(II), iron(III), platinum(IV) and nickel(II) are found to partition preferentially to one of the phases of the acidic aqueous biphasic system and it is here shown that it successfully allows the difficult separation of Co from Ni , here studied at 24 and 50 °C.

The role of association of ions in ionic liquid/molecular solvent mixtures on metal extraction.

Several mixtures of butyl acetate (BA) and an ionic liquid (1-methyl-3-octylpyrrolidinium bis(trifluoromethylsulfonyl)imide, [CCPyrro][NTf], 1-octyl-pyridinium bis(trifluoromethylsulfonyl)imide, [CPyr][NTf], 1-butyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide, [CCIm][NTf] or 1-octyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide, [CCIm][NTf]) have been characterized by measuring density, viscosity and conductivity, from pure BA to pure ILs at 298.15 K. The ionicity of these mixtures has been determined on the basis of electrical conductivity and NMR spectroscopy.

Quantitative extraction of Rh(iii) using ionic liquids and its simple separation from Pd(ii).

The extraction of Pd(ii) and Rh(iii) from acidic solutions containing between 1 and 8 M HCl towards three ionic liquids, namely [P][Cl], [P][Br] and [P][DCA], based on the trihexyltetradecylphosphonium cation ([P]) and chloride, bromide or dicyanamide (DCA) anions, respectively, is reported. Extraction of Pd(ii) is quantitative up to 6 M HCl (D > 3000). A value of 258 for the distribution coefficient of Rh(iii) extracted from 1 M HCl towards [P][Br] is also reported.

Dramatic Changes in the Solubilities of Ions Induced by Ligand Addition in Biphasic System D2O/DNO3//[C1C4im][Tf2N]: A Phenomenological Study.

The solubilities of C1C4im(+) and Tf2N(-) in nitric aqueous phases have been measured for several ligand types and concentrations (0.04 M tributylphosphine oxide, 0.05 M N,N'-dimethyl-N,N'-dibutylmalonamide, 0.

Rationale for the implementation of reference electrodes in ionic liquids.

A thorough investigation of the reference electrodes for electrochemical measurements is presented in three ionic liquids (ILs), namely 1-butyl-3-butylimidazolium bis(trifluoromethanesulfonyl)imide [BMIM][Tf2N], 1-octyl-3-butylimidazolium bis(trifluoromethanesulfonyl)imide [OMIM][Tf2N] and 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide [BMPyrr][Tf2N]. The influence of technical aspects such as internal resistance, scan rate and concentration of the active species on cyclic voltammetry has been investigated using three quasi-reference electrodes (QREs) (AgCl, Pt, and Pd) and three reference electrodes (REs) (Fc(+)/Fc/Pt, Ag(+)/Ag, and Cl(-)/AgCl/Ag). The results show that the internal resistance has to be taken dynamically into account during any cyclic voltammetry experiment.

Possibilities and limitations in separating Pt(IV) from Pd(II) combining imidazolium and phosphonium ionic liquids.

An investigation on a process designed for separating Pt(IV) and Pd(II) dissolved in acidic aqueous solution containing HCl using two ionic liquids, 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([OMIM][NTf2]) and trihexyltetradecylphosphonium bromide (Cyphos 102), is presented. To this end, the single extraction of platinum in [OMIM][NTf2] has been investigated as a function of the initial concentration of Pt(IV) ions dissolved in 1 M HCl. The distribution coefficient for Pt(IV), present in water as a PtCl6(2-) anion, decreases with the concentration of Pt(IV).

Selective extraction of gold and platinum in water using ionic liquids. A simple two-step extraction process.

We report an all-ionic liquid process for the separation of tetrachloroaurate and hexachloroplatinate complexes. In a first step, gold is removed from water by liquid-liquid extraction with a hydrophobic ionic liquid, 1,2-dimethyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide. Platinum is subsequently extracted from the solution in the presence of KSCN using 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide.

Correlating the structure and composition of ionic liquids with their toxicity on Vibrio fischeri: A systematic study.

A systematic screening of the toxicity of ionic liquids (IL) towards Vibrio fischeri, a bioluminescent marine bacteria generally used in ecotoxicological bioassays, was carried out. The objectives of this work were to find hydrophilic or hydrophobic low toxicity IL and to investigate structure-toxicity relationship of IL. Toxicity of 54 IL to V.

A new ozone denuder for aerosol sampling based on an ionic liquid coating.

A new ionic liquid 1-octyl-3,5-dimethylpyridinium iodide ([O35LUT](+)[I](-)) was synthesized and utilized as coating for an ozone denuder device based on a high-volume aerosol sampler (30 m(3) h(-1)). Particle transmission of the denuder was studied, and over 99% of particles ranging from 10 to 2,500 nm were transmitted. The device, containing 4.

In vitro cytotoxicities of ionic liquids: effect of cation rings, functional groups, and anions.

In vitro cytotoxicities were measured for ionic liquids (ILs) containing various cations and anions using the MCF7 human breast cancer cell line. We measured the cytotoxicities of ionic liquids containing the cations pyridinium, pyrrolidinium, piperidinium, or imidazolium with various alkyl chain lengths, and the anions bromide, bis(trifluoromethanesulfone)imide (Tf(2)N), trifluoromethylsulfonate (TfO), or nonafluoromethylsulfonate (NfO). Three new hydrophobic, task-specific ionic liquids (TSILs), namely, [MBCNPip](+)[Tf(2)N](-), [MPS(2)Pip](+)[Tf(2)N](-), and [MPS(2)Pyrro](+)[Tf(2)N](-) designed for metal-ion extraction were also evaluated.

Differential effects of unopposed versus opposed hormone therapy, tibolone, and raloxifene on substance p levels.

Objective: To evaluate the effects of unopposed therapy (conjugated equine estrogens [CEE]) vs. opposed therapy (CEE and medroxyprogesterone acetate), tibolone, and raloxifene on serum substance p levels.

Design: Clinical study.

Isolation of salmonella from minced meat by the use of a new procedure of enrichment.

In the examination of 526 samples of minced meat for the presence of salmonellae, a preliminary pre-enrichment in buffered peptone water was made. From this medium enrichments were made, for each sample of meat, in the usual Rappaport's medium (R25), incubated at 37 degrees C, and in Muller-Kauffmanns tetrathionate broth, incubated at 43 degrees C. Moreover, an enrichment was also made in a strongly modified Rappaport's medium, containing much less malachite green (R10), incubated at 43 degrees C.

[A new procedure of "Salmonella" enrichment (author's transl)].

We have prepared a modification of Rappaport's medium by reducing the content of themalachite green oxalate: medium R10, which is incubated at 43 degrees C instead of 37 degrees. These two modifications allow a satisfactory growth of a wide range of Salmonella and a better inhibition of competing organisms than the original medium of Rappaport incubated at 37 degrees and than Muller-Kauffmann's medium incubated at 43 degrees.

[New serotype of Salmonella of sub-strain II isolated in Greece: Salmonella 3,10 : 1,z-28 : 1,5].

A new Salmonella serotype, of sub-genus II, Salmonella 3,10 : 1,z28 : 1.5, has been isolated in Greece from refrigerated minced meat imported from South America.