Use of methyltrioctyl/decylammonium bis 2,4,4-(trimethylpentyl)phosphinate ionic liquid (ALiCY IL) on the boron extraction in chloride media

Abstract

Recent restriction of boron concentration in drinking water has produced some problems in the seawater desalinization plants because the rejection of boron in most of the plants is inadequate. Three ionic liquids derived from Cyanex 272 as an anion with different cations (from Aliquat 336, Cyphos IL 101 and Cyphos IL 167) were prepared to be used as boron extractants. Liquid–liquid extraction experiments were carried out to evaluate the viability of boron separation from high chloride media. The effect of ILs and boron concentration and pH were determined. Successive extractions, maintaining the organic phase, provided satisfactory results in order to implement these ILs on supported liquid membrane technologies. The use of the ionic liquid as a carrier can overcome the inconvenience associated with the membrane stability. In this sense, the ionic liquids ALiCY and the mixture of Cyphos IL 101 and Cyphos IL 167 with Cyanex 272 have been tested as liquid carrier for boron separation by using a flat sheet supported liquid membrane. The results obtained allow us to think about the application of this kind of ILs on the process intensification to remove boron from chloride solutions.