Extraction of Ruthenium using Both Tertiary and Quaternary Amine from Chloride Media

Abstract

Ruthenium extraction from a solution bearing 0.1 g/l Ru and 0.0358 M HCl was independently carried out with Alamine 336 and Aliquat 336 in kerosene with tri-n-butyl phosphate as the phase modifier. The effect of various parameters such as concentrations of extractant, hydrochloric acid, sodium chloride and TBP on extraction of ruthenium(III) was investigated. Ruthenium extraction increased with increasing extractant concentration up to 25% beyond which it decreased. With Alamine 336, the percentage extraction increased with increasing HCl concentration up to 6 M and then it decreased, but that with Aliquat 336 increased up to 4 M, and decreased beyond that. Ruthenium extraction from 4.5 M NaCl solution using 25% Aliquat 336 and 20% TBP in kerosene was maximum and that from a 2 M NaCl solution using Alamine 336 was maximum. The extracted species for Alamine 336 and Aliquat 336 were R 3 NH + RuCl . and R 3 NCH RuCl , respectively. The effect of various diluents such as kerosene, benzene, toluene, xylene, hexane, and cyclohexane on extraction of ruthenium was studied. The extraction isotherm with 25% Aliquat 336 indicated quantitative extraction in two stages both at O:A ratio of 1:1 and 2:1. The thermodynamic parameters such as ΔH, ΔG, and ΔS were also determined.