On the example of copper fulvate, it is discussed the method of calculation of stability constants of fulvic complexes. At pH = 8, the complex formation of copper(ll) ions with fulvic acids was studied by the solubi...On the example of copper fulvate, it is discussed the method of calculation of stability constants of fulvic complexes. At pH = 8, the complex formation of copper(ll) ions with fulvic acids was studied by the solubility method. Fulvic acids were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal (BAU, Russia) was used as a sorbent. The suspension of copper(If) hydroxide was used as the solid phase, on which was added the increasing quantity of standard solution of fulvic acids. In diluted solutions, at pH = 8 the dominant form of copper(lI) is copper dihydroxo complex Cu(OH)^zO. It was established that in the Cu(OH)2 (solid)-Cu(OH)^20 (solution)-FA^2-H20 system, dominates copper dyhydroxo fulvate complex with the structure 1:1, [Cu(OH)2FA]^2. The average stability constant of copper dyhydroxo fulvate complex was calculated based on experimental data fl [Cu(OH)2FAJ^2 = 4.5× l0^5.展开更多
文摘On the example of copper fulvate, it is discussed the method of calculation of stability constants of fulvic complexes. At pH = 8, the complex formation of copper(ll) ions with fulvic acids was studied by the solubility method. Fulvic acids were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal (BAU, Russia) was used as a sorbent. The suspension of copper(If) hydroxide was used as the solid phase, on which was added the increasing quantity of standard solution of fulvic acids. In diluted solutions, at pH = 8 the dominant form of copper(lI) is copper dihydroxo complex Cu(OH)^zO. It was established that in the Cu(OH)2 (solid)-Cu(OH)^20 (solution)-FA^2-H20 system, dominates copper dyhydroxo fulvate complex with the structure 1:1, [Cu(OH)2FA]^2. The average stability constant of copper dyhydroxo fulvate complex was calculated based on experimental data fl [Cu(OH)2FAJ^2 = 4.5× l0^5.