title: Enhancement of As(V) adsorption onto activated sludge by methylation treatment.
abstract: Biosorption properties of arsenate [As(V)] onto activated sludge were investigated in batch systems. The adsorption of As(V) onto sludge increased from 23 to 266 microg/g dry weight through the methylation of the activated sludge. This increase resulted from neutralization of carboxylic groups via the methylation process. The pH effect of As(V) uptake was also investigated and As(V) adsorption by methylated sludge decreased significantly at high pH (pH > 11) due to competition between As(V) and OH(-) ions for binding sites distributed on sludge surfaces. In contrast, low pH favored As(V) adsorption by methylated sludge because of the elevated quantities of positively charged functional groups. The results suggest that methylated activated sludge may provide promising applications for the simultaneous removal and separation of As(V) from aqueous effluents.
authors.affiliation: Center for Resource Management, Korea Institute for Defense Analyses (KIDA), Seoul, 130-650, South Korea.
authors.forename: So-Young
authors.initials: SY
authors.lastname: Kang
authors.forename: Dong-Wook
authors.initials: DW
authors.lastname: Kim
authors.forename: Kyoung-Woong
authors.initials: KW
authors.lastname: Kim
mesh_terms: D000327:Adsorption; D001149:Arsenates / Q000737:chemistry / Q000302:isolation & purification*; D001665:Binding Sites; D004785:Environmental Pollutants / Q000302:isolation & purification; D015386:Hazardous Substances / Q000302:isolation & purification; D006863:Hydrogen-Ion Concentration; D008745:Methylation; D012722:Sewage / Q000737:chemistry*
chemical_list: D001149:Arsenates; D004785:Environmental Pollutants; D015386:Hazardous Substances; D012722:Sewage; C025657:arsenic acid