Abstract

The conditions for a quantitative fulfillment of the reaction between Al3+ and EDTA in the presence of plant tanning extracts have been studied in detail. As a result we have established a fast complexometric method with residual titration for the determination of Al2O3 in complex coloured residual tanning solutions. The absence of systematic errors in the proposed procedure is proved. The repeatability of the method is very good, the standard deviation s = 0.01g/l Al2O3 for concentrations of Al2O3 0.37g/l and 1.92g/l. K+, Na+, and Ca2+ do not interfere with the procedure.