1993 Volume 42 Issue 6 Pages T83-T88
Zinc, cadmium, lead and copper ions in river water were determined by differential pulse anodic stripping voltammetry. The recommended procedure was as follows. A sample solution (7 ml) was taken into a cell; 0.5 ml of a mixed solution of 0.1 M tartaric acid and 0.5 M ammonium acetate was added as the supporting electrolyte. After bubbling nitrogen gas through the sample solution for 10 min, it was pre-electrolyzed for 5 minutes with a hanging mercury drop electrode at a potential of -1.4 V vs. SCE. Upon standing for 30 s, the pulse potential was fixed at 50 mV. The potential was immediately scanned from -1.4 V to +0.2 V vs. SCE at a scan rate of 10 mV/s for the dissolution of ions. Each ion was determined based on the peak currents of the voltammogram. Zinc in the range of 8.0×10-91.3×10-5 M, cadmium in the range of 8.0×10-95.0×10-5 M, lead in the range of 8.0×10-93.8×10-6 M and copper in the range of 8.0×10-92.5×10-5 M could be determined by this method. This method was applied to the determination of zinc, cadmium, lead and copper ions in practical river water. The analytical values agreed fairly well with those of ICP-AES. The effects of some concomitant ions were also investigated.
