2003 年 40 巻 p. 237-245
Adsorption experiments using three types of model flocs and various DOM were conducted for the purpose of characterization of DOM based on the adsorption principals. The model flocs were (1) ferric oxide under pH=9.5 (Fe9.5) acting as the absorbent by ligand exchange, (2) ferric oxide under pH=6.5 (Fe6.5) as the absorbent both by ligand exchange and by charge neutralization, and (3) silica with cationic polyacrylamide (Si+C) as the absorbent by cation bridging. The DOM samples included lake water as well as amino acids, sugars, organic acids, protein, polysaccharide, humic acid, and lignin. The comparison of the DOM concentrations before and after the adsorption experiment indicated that DOM with low molecular weight was not adsorbed by all the model flocs. The adsorption potential of DOM was evaluated as the residual ratio of DOM after adsorption experiment in the case of 3.6g/L floc concentration. The potential varied among the DOM as lake water<lignin<albumin≅starch≅humic acid at the conditions of Fe9.5 and Fe6.5. Under the condition of Si+C, the potential was lower compared with Fe9.5 and Fe6.5 except for albumin. The selective adsorption of DOM with E260 was observed, and the selectivity was highest under the Si+C condition.