2,6-DIMETHYL-4-MERCAPTOQUINOLINE AS A NEW ANALYTICAL REAGENT FOR SPECTROPHOTOMETRIC DETERMINATION OF COPPER (II)
DOI:
https://doi.org/10.46991/PYSUB.2026.60.1.088Keywords:
copper (II), spectrophotometry, mercaptoquinolin, analytical reagent, complex formationAbstract
A new efficient spectrophotometric method has been elaborated for determination of copper (II) ions using 2,6-dimethyl-4-mercaptoquinoline (R) as the analytical reagent. It has been established that the molar ratio between the reactants is Cu(II) : R = 1 : 2. The conditions for copper (II) complexation, including the effects of pH, reagent and copper (II) concentrations, and reaction duration have been studied. It has been shown that resulting complex possesses intense absorption in the visible region at a wavelength of 440 nm. It has been also shown that the system obeys Bouguer–Lambert–Beer law over a concentration range of 0.032–0.8 mg/25 mL (1.28–32 μg/mL). The average value for molar absorption coefficient is 9460. The influence of extraneous ions has been studied. The method has been successfully applied for copper determination in a standard bronze sample. The proposed reagent was shown to possess high sensitivity and selectivity compared to well-known sulfur containing reagents.
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