Determination of Cu(II) in environmental water samples using polymer inclusion membrane-TAC optode in a continuous flow system

This study describes the selective determination of copper (II) using the recently developed polymer inclusion membrane (PIM) in a river water system via a continuous flow (CF) system. The PIM is composed of 42% di(2-ethlyhexyl) phosphoric acid (D2EHPA) as the carrier, 8% dioctyl phthalate (DOP) as the plasticizer and 49% poly(vinyl chloride) (PVC) as the base polymer. The colorimetric reagent that is used for the spectrophotometric determination of copper (II) is 1% 2-(2-thiazolylazo)-p-cresol (TAC). In this system, copper (II) is extracted into the PIM as the copper-D2EHPA complex which afterwards reacts with TAC producing green copper −TAC complex. The quantitative measurements are conducted by using light emitting diode (LED) and light dependent resistor (LDR) connected to a voltmeter. Results are obtained through the voltage readout on the computer. Under optimal conditions, the sensor has a limit of detection (LOD) of 0.10 mg L−1 and a limit of quantitation (LOQ) of 0.35 mg L−1. The CF-PIM-TAC system was successfully used in the determination of Cu(II) in river systems near mining sites.