Removal of chlorophenols from aqueous solution by fly ash.
Fly ash from coal-fired thermal power plants can be used for the removal of 2-chlorophenol (2-CP) and 2,4-dichlorophenol (2,4-DCP) with enthalpy changes of about -3 kcal/mol. The amounts of 2-CP and 2,4-DCP removed are affected by the pH value of the solution. The efficiency of removal improves when the pH value is less than the pK(a) values of 2-CP and 2,4-DCP, respectively. The adsorbed amount of chlorophenol by fly ash is also affected by particle diameter, carbon content, and the specific surface area of the ash used in this study. As expected, more adsorption takes place with fly ash of higher carbon content and larger specific surface area. Moreover, the adsorbed amount of chlorophenol is not influenced by the matrix in the wastewater, as shown by studying the removal of 2-CP and 2, 4-DCP in wastewater from a synthetic fiber plant. Chlorophenols in the wastewater were also removed efficiently through a fly ash column, with breakthrough times being inversely proportional to flow rates.
Department of Environmental Engineering, National Chung-Hsing University, Taichung 402, Taichung, Taiwan.
P C
PC
Kao
J H
JH
Tzeng
T L
TL
Huang
D000327:Adsorption; D002244:Carbon / Q000032:analysis / Q000737:chemistry*; D002733:Chlorophenols / Q000737:chemistry*; D003031:Coal; D060729:Coal Ash; D005374:Filtration; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D010316:Particle Size; D052638:Particulate Matter; D012212:Rheology; D013499:Surface Properties; D013783:Textile Industry; D014867:Water / Q000737:chemistry
D002733:Chlorophenols; D003031:Coal; D060729:Coal Ash; D007220:Industrial Waste; D052638:Particulate Matter; D014867:Water; D002244:Carbon; C030683:2-chlorophenol; C004762:2,4-dichlorophenol