QADAB的合成及其固相萃取光度法测定铜

Synthesis of QADAB and spectrophotometric determination of Copper (Ⅱ) by the solid phase extraction

合成了新试剂2-(2-喹啉偶氮)-1,3-二氨基苯(QADAB),研究了其与铜的显色反应,在pH=4 0的磷酸盐缓冲介质中,CTMAB存在下,QADAB与铜反应生成2∶1稳定配合物,该配合物可被WatersPorapak Sep Pak C18固相萃取小柱萃取,用乙醇(内含1%的乙酸)洗脱后用光度法测定,在乙醇相中配合物λmax=555nm,ε=8 08×104L·mol-1·cm-1.铜含量在0～1 0μg·mL内符合比尔定律,方法用于环境水样中微量铜含量的测定,结果令人满意.

Based on synthesis of 2-(2-quinolinylazo)-1,3-diaminobenzene (QADAB),the color reaction of QADAB with copper(Ⅱ) and the solid phase extraction of its colored complex with Waters Porapak~ Sep-Pak-C18 cartridge, a new method for the determination trace of copper(Ⅱ) was studied. In the medium of CTMAB and the presence of pH=4.0 KH_2PO_4-K_2HPO_4 buffer solution. QADAB can reacts with copper (II) to form a stable 2∶1 complex. The colored complex can be extracted by C_(18) cartridge and eluted by ethanol, then can be determined by spectrophotometry. The molar absorptivity of the complex is 8.08×10~4*!L·mol^(-1)·cm^(-1) at 555*!nm. Beer's law is obeyed in range of 0～1.0*!μg/mL. This method can be applied to the determination of copper in water with good results.