Presence Of Tetrabutylammonium Ions Research Articles

Solvent Extraction of Trivalent Lanthanoide Ions into Carbon Tetrachloride as Ternary Complexes with a ß-Diketone and Tetrabutyl-Ammonium Ions

Solvent extraction of La 3+ , Eu 3+ and Lu 3+ ions into carbon tetrachloride with thenoyltrifluoroacetone(Htta; HA) in the absence and presence of tetrabutylammonium ions(tba + ) is measured and the effect of various factors on the extraction equilibrium is considered. The data are treated on the basis of association equilibrium of the neutral chelate, MA3, with the extracted ion-pairs of the reagents, A - .B + , in the organic phase

SOLVENT EXTRACTION OF ZINC(II) ANIONIC g-DIKETONATE COMPLEXES AS ION-PAIRS WITH TETRABUTYLAMMONIUM IONS

ABSTRACT Solvent extraction equilibria of zinc(II)with five 6-diketones(HA)in carbon tetrachloride-aqueous 1 mol dm−3NaN03systems are studied in the absence and presence of tetrabutylammonium ions(tba+The distribution data of zinc(II)in the absence of tba+ are explained in terms of extractions of uncharged ZnA2 complex from the aqueous phase where the ZnA+, ZnA2and ZnA3complexes are formed, and those in the presence of tba+ in terms of extraction of the ZnA3~tba+ ion-pairs in addition to the uncharged one. The extraction of the ZnA3-tba+species is better with hexafluoroacetylacetone than with trifluoroacetyl-acetone. It is better when the extractant is benzoyltri-fluoroacetone than when it is trifluoroacetylacetone and this is explained in terms of a greater increase in the hydrofobic character by formation of the tris-complex from the bis-complex with the larger ligand. However, the extraction with acetylacetone and benzoylacetone is not affected by though the formation of the tris-chelate with these lig...

Behaviour of dihyroxynaphtalenes in a reversed-phase chromatographic system

The influence of the organic modifier of the mobile phase, the ionic strength, the control of pH by different procedures, and the presence of tetrabutylammonium ion on the separation of seven isomeric dihydroxynaphthalenes and two quinones derived from them was studied by using silica gel modified chemically with octadecyls as a stationary phase. Substantial differences in the retention and in the selectivity of the separation with a change of the organic modifier or with a change in its concentration are caused by the contribution of the sttinary phase to the retention of the solutes under study. Anomalous broadening of peaks 2,3-dihydroxynaphthalenes in acetate buffer and in solution of sulphuric acid was ascribed to the formation of complexes with heavy metals deposited in the stationary phase.

A polarographic study of methionine complexes of nickel and cobalt

A polarographic study of nickel and cobalt complexes of methionine has been carried out. In sodium perchlorate and tetramethyl-ammonium bromide (TMAB) media, catalytic hydrogen waves were observed owing to the lowering of hydrogen overvoltage on mercury by the adsorption of these complexes on the dropping electrode. The presence of tetrabutylammonium ion inhibits the catalytic activity.