研究了 6 ,6″—二甲基— 4′—苯基 - 2 ,2′ :6′ ,2″—三联吡啶 (TPY)与Cr(Ⅵ )的显色反应。在pH5 .0 6 .2的HAc -NaAc介质中 ,Cr(Ⅵ )与该试剂形成稳定的橙色络合物 ,其吸收峰波长λmax=36 7nm ,表观摩尔吸光系数为 1.72× 10 5L(mol·cm) -1,Cr(Ⅵ )浓度在 1.3～ 76 μg/L内服从比尔定律。精密度和准确度实验结果表明 ,该方法准确 ,可用于环境水及电镀水中铬 (Ⅵ )的测定 The color reaction of 6,6 “- dimethyl - 4’- phenyl - 2, 2 ’: 6’, 2” - terpyridine (TPY) with Cr (Ⅵ) was studied. Cr (Ⅵ) forms a stable orange complex with this reagent in the HAc-NaAc medium at pH5 .0 6 .2, with an absorption peak wavelength λmax = 367 nm and an apparent molar absorptivity of 1.72 × 10 5 L (mol · Cm) -1, and the concentration of Cr (Ⅵ) obeys Bill’s law within 1.3 ~ 76 μg / L. The precision and accuracy of the experimental results show that the method is accurate and can be used for the determination of chromium (Ⅵ) in environmental water and electroplating water