Spectrofotometric determination of copper in sugar cane spirit using biquinoline in the presence of ethanol and Triton X-100

The present paper proposes a method for molecular spectrophotometric determination of copper in sugar cane spirits. The copper(I) reacts with biquinoline forming a pink complex with maximum absorption at 545 nm. The reaction occurs in the presence of hydroxylamine, ethanol and Triton X-100 tensioative. Determination of copper is possible in a linear range 0.2–20.0 mg L−1 with a detection limit 0.05 mg L−1. The great advantages of the proposed methodology are the elimination of liquid–liquid extraction step and the use of toxic organics solvents, like dioxane, to dissolve the reagent.