RESUMO
A quaternary ammonium-based room temperature ionic liquid trioctylmethylammonium salicylate (TOMAS) has been studied as an extractant of transition metal ions (Fe(3+), Cu(2+), Ni(2+), Mn(2+)) in aqueous solutions. The effect of pH value on the recovery of metal ions has been investigated. The mechanism of extraction into the ionic liquid has been proposed. The possibility of stripping voltammetric determination of transition metals in aqueous solutions using TOMAS-modified electrodes has been demonstrated.
RESUMO
Ionic liquids that melt slightly above room temperature (and may be called low-melting ionic solids, LMISs) were used as sensing materials for the detection of ions in aqueous solutions. A simple procedure based on the consecutive melting and further solidification of the LMISs was applied to prepare solid-contact ion-sensitive electrodes. A potentiometric response toward a number of anions was observed, and the possibility of altering the selectivity by incorporating additional ionophores into the LMIS matrix was demonstrated.
Assuntos
Eletroquímica/métodos , Eletrodos Seletivos de Íons , Íons , Alumínio/química , Ânions , Varredura Diferencial de Calorimetria/métodos , Eletrodos , Modelos Químicos , Potenciometria/métodos , Salicilato de Sódio/química , Soluções , Temperatura , Termogravimetria/métodos , Fatores de TempoRESUMO
Cellulose films containing entrapped analytical reagents suitable for metal-ion detection are produced by joint dissolution of cellulose and the reagents in ionic liquids then precipitation with water. The conditions of preparation of these test materials have been optimized and their properties have been studied. The film obtained by use of the ionic liquid 1-butyl-3-methylimidazolium chloride and 1-(2-pyridylazo)-2-naphthol has been used for colorimetric determination of divalent zinc, manganese, and nickel with detection limits at the 10(-6) mol L-1 level.