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In this issue, we describe the synthesis and analysis of new trichloride compounds: tetraphenylphosphonium trichloride, (C6H5)4PCl3, and pyridinium trichloride, C5H6NCl3. Those are vibrationally studied and compared with tetrabutylammonium trichloride ((n-C4H9)4NCl3) and tetraphenylarsonium trichloride. Raman spectroscopy shows an intense stretching band ν1 and 270 cm−1. Its straightforward intensity is explained by the preresonance spectra of the Cl3− ion. Stretching constants of trichlorides and other trihalide ions (Br3−, I3−, BrCl3−, I2Br−, ICl2−) are compared each other.

The electronic spectra of organic trichlorides (n-C4Hg)4NCl3 and ϕ4AsCl3) in acetonitrile and dichloromethane are studied and compared with spectra of other trihalide ions: Br3−, I3−, BrCl2−, ICl2−. The apparent constant of the equilibrium, Cl2 + Cl− − Cl3−, is evaluated in acetonitrile with lithium chloride and tetrabutylammonium chloride. Typical trichloride absorption bands in saturated chlorine brines of NaCl (or hydrochloride solutions) are not observed and thus no trichloride complex ions are formed in aqueous phase.

L'article presente une methode de preconcentration de traces d'elements lourds (Zn, Hg, Cr, Cd, Cu) dans les eaux en vue de leur dosage par activation neutronique. Le choix s'est porte sur la resine complexante Dowex Al. Les rendements de fixation ont ete determines pour les elements cites. L'influence du pH et de la force ionique a ete etudiee et les conditions optima de fixation ont ete etablies. Cette etude montre que la resine Dowex A1 s'avere satisfaisante.

In this paper, we study the oxydant concentration stability of diluted halogen solutions of bromine, chlorine in organic solvents: acetonitrile, nitromethane, N,N-dimethylformamide, N,N-dimethylacetamide, 1 methylpyrrolidinone-2, tetrahydrofuran, dimethylsulfoxide, tetramethylurea and tetramethylthiourea. Raman spectroscopy examinations of halogen Solutions show undoubted formation of trichloride and tribromide ions in N,N-disubstituted amide solvents. This specific chlorine solvation explains the immonium chloride formation observed during styren chloration in N,N-dimethylformamide. Bromine solvation in dimethylsulfoxide and other nucleophilic solvents are also studied.

This paper studies the equilibrium HOCl in NaCl brines and the variation of the apparent constant (ka) with ionic strength and temperature. Several reactions (decomposition, chloride formation and loss of Cl(I)) that remove the equilibrium are also examined. The brine acidity is experimentally determined and compared to the concept of pH.

L'article decrit un procede de dosage de plusieurs elements metalliques: aluminium, cadmium, cuivre, fer, plomb et zinc a l'etat de traces dans les eaux. Les elements sont extraits sous forme de chelates metalliques de β-dicetones fluorees (trifluoroacetyl-acetone, thenoyltrifluoroacetone) ou de la thiothenoyltrifluoroacetone au moyen de propionate d'ethyle. Ils sont ensuite doses par spectrophotometrie d'absorption atomique de l'extrait organique. Les courbes d' etalonnage sont lineaires de 0 a 100 μg/l au moins; les sensibilites varient du ppb a la dizaine de ppb selon les metaux. Le procede peut etre etendu a de nombreux autres elements.