铜-5-Br-PAND-TritonX-100体系析相法测定天然水中痕量铜

Determination of Trace Copper in Natural Water by Phase-separation Method Using 5-Br-PADN-Trtion X-100

研究了显色剂 1 - [(5-溴 - 2 -吡啶 )偶氮 ]- 2 ,7-萘二酚 (简称 5- Br- PADN)在 Triton X- 1 0 0存在下 ,用浊点析相分光光度法测定天然水中痕量铜 ( )。在p H8.3～ 9.7的氨水 -氯化铵缓冲溶液中 ,配合物最大吸收波长为 λmax=543nm,相当于 Sandell灵敏度为 0 .0 0 0 1 4μg/cm,铜量在 0～ 2 0μg/2 50 m L范围内符合比尔定律 ,方法已用于测定天然水中的痕量铜。

A phase separation method was described for determination of copper in natural water using the system of Cu(Ⅱ) 5 Br PADN Triton X 100. The suitable pH range was from 8.3 to 9.7. The complex shows maximum absorption wavelength at 543 nm and sandell sensitivity of 0 00014 μg·cm -2 . Beer's law is obeyed in the range for 0～20 μg/250 mL for Cu(Ⅱ). The method was applied to determination of trace Cu in natural water with satisfactory results.