The simultaneous dissolution of tetraoctylammonium bromide and sodium N-lauroyl sarcosinate in water leads to the in situ formation of a water-immiscible ionic liquid, tetraoctylammonium N-lauroyl sarcosinate. The new phase formed can extract cadmium, cobalt, copper, nickel, lead, and zinc ions from aqueous solution in the presence of 4-(2-pyridylazo)resorcinol (PAR), while it can extract cadmium ions in the absence of PAR.