Response surface methodology applied to extraction optimization of gold(III) by combination of imidazolium-based ionic liquid and 1-octanol from hydrochloric acid

ABSTRACT

Value and high demand for gold have encouraged its exploration and recoverability from secondary sources. This study is aimed to investigate the extraction recovery of gold(III) from hydrochloric acid media using 1-butyl-3-methylimidazolium hexafluorophosphate and 1-octanol. The influence of initial ion concentration, 1-butyl-3-methylimidazolium hexafluorophosphate concentration, acidity of solution, volumetric ratio of aqueous to organic phase, and extraction time are examined. Central composite design in response-surface methodology was applied for the optimization of the effective parameters. The extraction recovery higher than 99% is achieved at the optimum conditions, which is close to the predicted response by the model (99.999%).

KEYWORDS:

• Gold(III)
• extraction
• 1-butyl-3-methylimidazolium hexafluorophosphate
• hydrochloric acid
• Response surface methodology