Table 1.

Equilibrium metal speciation in M2M and NMS media at different total copper concentrationsa

MediumMetal speciationResult obtained with total copper (μM)
0.020.1151020
M2MChelated Cu (%)100100999694
Precipitated Cu (%)000.53.65.6
Free Cu (%)0.0890.0480.0130.0140.015
pCub10.710.39.28.88.5
Soluble Fe (%)169141111
Precipitated Fe (%)8491868989
NMSChelated Cu (%)10094937059
Precipitated Cu (%)05.97.23038
Free Cu (%)0.160.140.080.212.8
pCu10.39.88.47.76.3
Soluble Fe (%)999968280
Precipitated Fe (%)113262100
  • a M2M and NMS have total iron concentrations of 0.9 and 9 μM, respectively.

  • b Free copper concentrations at equilibrium, reported as the negative log of [Cu2+].