Use of a polarographic method to determine copper, nickel and zinc constants of complexation by extracellular polymers extracted from activated sludge

Lead Complexation of Soluble and Bound Extracellular Polymeric Substances from Activated Sludge: Characterized with Fluorescence Spectroscopy and Ftir Spectroscopy

“…the conditional stability constant (logK a ) for both peak A of SEPS and peak B of BEPS decreased with increasing pH values, indicating that moderately acidic conditions are more favorable for complexation of the fluorescent components in SEPS and BEPS with Pb(II). The values of logK a were close to those for complexation of EPS with heavy metals determined using other methods (13,14,15), using polarographic methods, the relative stability constants of EPS metal complexes, log(K), were determined to be 1.54-3.35 for Cd, 0.45-1.28 for Pb, 3.0-4.4 for Cu and 2.6-3.0 for Ni, respectively. The conditional binding constant for Cu(II) and Cd(II) and Pb(II) to EPS from activated sludge were 3.2-4.5 and 3.7-5.0, respectively (10).…”

Effects of extraction procedures on metal binding properties of extracellular polymeric substances (EPS) from anaerobic granular sludges

“…Then the concentrations of EPS-Pb and EPS-Cd binding sites were determined using the Chau's graphic method [14]. The amount of EPS binding sites initially occupied was not taken into account for the determination of the total number of binding sites in EPS extracts due to the very low Cd and Pb content in extracted EPS (less than 1 per thousand).…”

Biosorption properties of extracellular polymeric substances (EPS) towards Cd, Cu and Pb for different pH values

“…The modelisation of the EPS saturation curves was carried out according to Ruzic's graphic methods and allowed [L] and K to be determined [18,26]. During the modelisation, error evaluation on the slopes and the y-intercepts was carried out.…”