高精度散射光度滴定法测定Al~(3+)的含量

目的　探讨利用高精度散射光度滴定法测定Al3 + 含量的可行性。方法　用氢氧化钠的标准溶液作滴定剂 ,采用高精度散射光度滴定法对Al3 + 的含量进行测定 ,并将测定的结果与络合滴定法的测定结果相比较。结果　高精度散射光度滴定法的精密度可小于 0 .2 % ,经F检验表明与络合滴定法相当 ;t检验结果表明高精度散射光度滴定法的均值与络合滴定法无显著性差异。结论　高精度散射光度滴定法可以用于Al3 + 的含量测定

Determination of Al~(3+) by highly-accurate nephelometric titration

OBJECTIVE To investigate the applicability of highly-accurate nephelometric titration in the determination of Al 3+ .METHODS A visible light-emitting diode (LED) was used as a light source and a photodiode served as the optical detector. Light on the detector created an electric current through the diode. The titration( Al 3+ solution) became turbid with the addition of the titrant(NaOH solution) and the intensity of the scattered light in the solution increased gradually. The intensity of the scattered light would reach the maximum at the stoichiometric point; thus, the titration end-point could be indicated. The result determined by the highly-accurate nephelometric titration was compared with that by compleximetry.RESULTS The precision of the highly-accurate nephelometric titration, which could be better than 0.2% under suitable conditions, was comparable to that of compleximetry by F -test. The accuracy of the highly-accurate nephelometric titration was comparable to that of compleximetry by t -test.CONCLUSION The highly-accurate nephelometric titration could be applied in the determination of Al 3+ .