Sorption of dyes from aqueous solutions onto fly ash.
Brown coal fly ashes were tested as potentially low-cost sorbents for the removal of synthetic dyes from waters. It was shown that both basic (cationic) as well as acid (anionic) dyes can be sorbed onto the fly ash. The adsorption can be described by the multi-site Langmuir isotherm. The sorption capacities were in the range of 10(-1)-10(-3)mmol/g and did not differ significantly for basic and acid dyes. The dye sorption decreased in the presence of organic solvents (methanol, acetone). The presence of oppositely charged surfactants exhibited a pronounced effect on the dye sorption-low concentrations of the surfactant enhanced sorption, whereas high concentrations solubilized the dyes and kept them in solution. Inorganic salts exhibited only a minor effect on the dye sorption. The sorption of basic dyes increased at high pH values, whereas the opposite was true for acid dyes.
Janos
Pavel
P
Faculty of Environmental Studies, University of Jan Evangelista Purkyne, Králova Výsina 7, 400 96 Ustí nad Labem, Czech Republic. janos@fzp.ujep.cz
Buchtová
Hana
H
Rýznarová
Milena
M
D002244:Carbon / Q000737:chemistry*; D060729:Coal Ash; D004396:Coloring Agents / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D052638:Particulate Matter; D013783:Textile Industry; D014873:Water Pollutants / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
D060729:Coal Ash; D004396:Coloring Agents; D007220:Industrial Waste; D052638:Particulate Matter; D014873:Water Pollutants; D002244:Carbon