Sn(Ⅳ)-DBPF-H_2QS-CTMAB显色体系的研究

Study on the Color System of Tin(Ⅳ)-4,5-Dibromophenylfluorone -8-hydroxyquinoline 5-sulfonic Acid-Cetyl Trimethyl Ammonium Bromide

在024～040mol/LH2SO4介质中,有溴化十六烷基三甲基铵存在下,Sn(Ⅳ)与8羟基喹啉5磺酸(H2QS)和4,5二溴苯基荧光酮(DBPF)形成有色的胶束混配络合物。络合物组成为Sn(Ⅳ)∶H2QS∶DBPF=1∶1∶2。最大吸收波长为540nm,表观摩尔吸光系数ε=142×105。在25mL溶液中,Sn(Ⅳ)在0～10μg范围内符合比尔定律。该法灵敏度和选择性均比无H2QS存在时好,用于铝合金及有机锡混料中锡的测定,结果满意。

In the medium of 0 24-0 40 mol/L H 2SO 4 and in the presence of cetyl trimethyl ammonium bromide, Tin(Ⅳ) forms a micellar mixed ligand complex with 8-hydroxyquinoline-5-sulfonic acid (H 2QS) and 4,5-dibromophenylfluorone(DBPF). The composition of complex is determined to be Sn(Ⅳ):H 2QS:DBPF=1:1:2 The maximum absorption of the complex is at 540nm and the apparent molar absorptivity of the complex is 1 42×10 5L·mol -1 ·cm -1 . Beer's law is obeyed in the range of 0-10μg Sn(Ⅳ) per 25mL. The sensitivity and selectivity of this method is higher than that of in the absence of H 2QS. The proposed method has been applied to determine Sn in aluminum alloy and mixture of organo-tin compound with satisfactory results.