Effects of extraction procedures on metal binding properties of extracellular polymeric substances (EPS) from anaerobic granular sludges.
The effects of the extraction procedure of extracellular polymeric substances (EPS) on their proton/metal binding properties were studied. Nine extraction procedures (one control, four physical and four chemical procedures) were applied to four types of anaerobic granular sludges. The binding capacities between the EPS and lead or cadmium were investigated at pH 7 by a polarographic method. The composition of the EPS extracts varied according to the extraction technique and the origin of the sludge. This induced differences in the pK(a)s and the binding sites density of the EPS extracts. The carry-over of the extractant in the samples strongly affects the properties of the EPS from chemical extraction protocols. Lead and cadmium seem to be bound differently with the EPS, a higher binding capacity was observed for Pb(2+) than for Cd(2+).
d'Abzac
Paul
P
Université de Limoges, Groupement de Recherche Eau Sol Environnement, EA 4330, 123 Av Albert Thomas, 87 060 Limoges, France.
Bordas
François
F
van Hullebusch
Eric
E
Lens
Piet N L
PN
Guibaud
Gilles
G
D000693:Anaerobiosis; D002104:Cadmium / Q000737:chemistry / Q000302:isolation & purification; D005110:Extracellular Space / Q000378:metabolism*; D007854:Lead / Q000737:chemistry / Q000302:isolation & purification; D008670:Metals / Q000737:chemistry* / Q000302:isolation & purification; D011108:Polymers / Q000737:chemistry*; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology; D018508:Water Purification
D008670:Metals; D011108:Polymers; D012722:Sewage; D002104:Cadmium; D007854:Lead