表面活性剂增感火焰原子吸收法测定铬

Atomic Absorption Spectrophotometry of Chromium by Using the Enhancing Effect of Surfactants

本文在空气—乙炔焰中,研究了阳离子表面活性剂溴化正辛基吡啶(OPB)和阴离子表面活性剂十二烷基苯磺酸钠(SDBS)对铬火焰原子化行为的影响,并探讨了机理.发现OPB和SDBS对铬均有显著的增感作用,在提高铬灵敏度的同时,亦提高了选择性.所拟定的分析方法的精密度和准确度良好,用于电镀厂污水中和铁基合金中铬的测定,结果满意.

In this paper the effect of cation surfactant, octyl pyridine bromide (OPB), and anion surfactant, sodium dodecyl benzene sulphonate (SDBS) on the atomi-zation behavior of chromium is studied in an air-acetylene flame. The results indicate that OPB or SDBS in test solution marked sensibilization effect is produced. The mechanism of enhancement and the interferences of the concomitant elements and their elimination are discussed. Under definite condition the recovery of chromium is 97.1 to 103.2%, the standard deviation and relative standard deviation are 0.036 and 1.2% (n=10) respectively in the SDBS system. The method has been applied to determination of chromium in the wastewater of electroplating and steel sample (7701, 1Cr21Ni17Ti) with satisfactory results.