Separation/preconcentration of trace copper by extraction into [C4mim] [PF6] RITL containing p-tert-butyl-calix[4]arene functionalized with o-phenanthroline prior to flame absorption atomic spectrometry

► A novel method for the analysis of copper(II) ► The inclusion complex of Cu(II)-TBCP was extracted into the RTIL phase. ► The extraction mechanism was approached. ► It was applied for the analysis of Cu(II) in water samples with satisfactory results.