Reliable determination of copper complex ions in synthetic wastewater using flame atomic absorption spectrophotometry

Forms of copper that are highly soluble in aquatic environments are used as chemical reagents in a variety of industries, especially copper complexes. Wastewater containing copper complexes can be difficult to treat and analyse. Normally, flame atomic absorption spectrophotometry (FAAS) is a favourable technique for analysing metal ions in wastewater, but is less reliable for copper analysis owing to the influence of copper oxides. To solve this problem, it is necessary to adjust the atomization and delay times. The objective of this study was to use FAAS to accurately determine the quantity of complexed copper in synthetic wastewater, using increased atomization and delay times. The method showed excellent linearity in the copper standard concentration range of 1–5 mg L−1. The sensitivity of the analysis was 0.023 mg L−1. The percentage of recovery and the relative standard deviation were 85.02% and 0.75%, respectively. The experimental results demonstrated that the estimation of uncertainty from preparation of working standard, repeatability uncertainty, instrument deviation, calibration curve and recovery uncertainty were 8.2 × 10−4, 4.49 × 10−4, 7.21 × 10−4, 21.25 × 10−4, and 98.19 × 10−4, respectively. Overall, the results showed the suitability of the FAAS method for determining copper in synthetic wastewater.