Complexation between metal ions and water soluble organic soil substances as analyzed by electrochemical techniques.

摘要

Conductometric and potentiometric titration of water extracts from soils using metal salt solutions (Cu, Al, Pb) were performed. A nonlinear dependence of electrical conductivity of water extracts on the concentration of metals added was established, which is caused by the formation of metal organic complexes proceeding with the participation of metal ions. A parameter describing the differential equivalent electrical conductivity ( Delta lambda ) was proposed which characterizes the complexation process, and a formula for the calculation of this parameter was given. The basic parameters of copper ion complex formation with water soluble organic substances of the extract were determined on the basis of conductometric titration of water extracts from soils using copper nitrate solution. These processes were shown to proceed differently for soddy and podzolic soils, the properties of which are known to differ significantly. An integrated parameter of the equivalent electrical conductivity for ligands of soil water soluble organic substances was assessed.Notes Translated from Vestnik Moskovskogo Universiteta. Pochvovedenie (2013) (1), 46-53 (Ru).