Cloud Point Extraction Method for Spectrophotometric Determination of Copper(II) in Real and Drinking Water Samples Using New Reagent (<i>Z</i>)-2-(((2,4-dinitrophenyl)imino)methyl)phenol

This method involved the spectrophotometric estimation of copper(II) using the new reagent (Z)-2-(((2,4-dinitrophenyl)imino)methyl)phenol, at a wavelength of maximum absorption of the colored compound at 420 nm, as well as the determination of optimal complex conditions for copper(II) determination. The calibration curve for the copper(II) ion complex with the reagent was established, and the concentration range according to Beer's law was between 10 and 20 μg mL−1, with a correlation coefficient of 0.9940, the molar absorption coefficient of 0.7930 × 103 L mol−1 cm−1, and Sandel's sensitivity of 0.08 μg cm−2. The copper(II) was then preconcentrated and determined using the cloud point extraction technique, and the complex formed's calibration curve was determined. The concentrations that adhered to Beer's law were found to be between 1 and 10 μg mL−1, with a correlation coefficient of 0.9965, molar absorption coefficient 0.1485 × 104 L mol−1 cm−1, and Sandel's sensitivity 0.0427 μg cm−2. The analytical method was subsequently used to detect the presence of copper(II) in drinking water samples, i.e., Eyun Baghdad, Saha, Sana, Nawar, Al-furqan, Pearl, and Aquafina. Compared with the outcomes of flame atomic absorption spectrometry, the results were analogous.