Study of apparent complexing capacities of trace heavy-metals in the Huanghe River Estuary

By the electroanalysis method combining the complexation titrating technique with the investigation of i_p~E_a^* characteristic curves, this paper measures apparent complexing capacities of trace heavy-metals in water samples from the Huanghe River Estuary. The results show that the order of apparent complexing capacities of trace heavy-metals in the samples is
Cu > Cd > Pb,
and that apparent complexing capacities of near shore sample are higher than those far from shore. The effect of ultraviolet irradiation on the dissociation of organic ligands and the adsorption effect of cell walls (cells being treated with acid and seawater respectively) are investigated. The reduction (on electrodes) mechanism of species of trace heavy-metals in seawater is approached by i_p~E_a^* characteristic curves.