大量铝及锰、镁、锌、镍存在下连续配位滴定铁、铜

THE CONTINUOUS COMPLEXOMETRIC TITRATION OF Fe AND Cu IN A LARGE AMOUNT OF Al, Mn, Mg Zn AND Ni

本文研究了在大量铝及锰、镁、锌、镍存在下,用EDTA连续配位滴定铁、铜的可行性.并根据实验结果,建立了在pH≤I时以NH_4SCN为指示剂,先用EDTA滴定铁,然后调整试液的pH0.8—I.I之间,加入过量的NH_4SCN,以变胺蓝为指示剂,再用EDTA连续配位滴定铜的测定方法.同时证实了共存离子不干扰铁、铜的连续滴定,且将该测定方法试用于人工合成试样及铝基合金试样中铁、铜的分析.

This paper discusses the feasibility of the continuous complexomechic titration of Fe and Cu with EDTA in the mixture which contains a large amount of Al, Mn, Mg, Zn and Ni Based on the results of the experiments, the determination method is established that when pH< 1 with NH4SCN as indicator, first titrate iron with EDTA, and then after regu- lating the test solution when pH is between 0.8-1,1 and puting in excess NH4SCN, again with EDTA the continuous complexometric titration of copper is determined with variamine blue as indicator. And it is proved that the presence of coexisting ions do not in- terfere with the continuous titration of iron and copper. This determination method is tried out to analyse the iron and copper in the test samples of artificial synthesis and aluminium alloy.