The adsorption and desorption behaviors of 17a-ethinylestradiol on various sludges derived from different treatment units of a sewage treatment plant were investigated using batch equilibration experiments. The results showed that adsorption process could be well described by pseudo-second-order kinetic model and fast adsorption played a main role. Adsorption ability varied as the order of aerobic sludge & anoxic sludge & primary sludge [ sludge cake [ anaerobic sludge. Adsorption/ desorption isotherms were well fitted by the modified Freundlich model, and K 0 f values increased with the organic matter content. Thermodynamic analysis indicated that 17a-ethinylestradiol adsorption/desorption was exothermic and conducted spontaneously. After heat treatment for removing the organic carbon, K 0 f values decreased by more than 78%, but organic carbon normalized adsorption constant was 7.76-29.51 mg/g. The 17a-ethinylestradiol adsorption capacity was found to decrease from 0.95-1.39 to 0.44-0.49 mg/g with sludge concentration increasing from 500 to 4,000 mg/L, being almost unchanged at pH 3-10 and sharply decreasing with pH [ 10. The adsorption capacity was also found to fluctuate in the range of 2.0-3.0 mg/g when Ca 2? concentration was \0.5 mol/L and increased rapidly above 0.5 mol/L. Addition of methanol and acetonitrile could improve 17a-ethinylestradiol desorption effect, which increased with the content of organic solvents, and the desorption degree of acetonitrile was higher than methanol.

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The effects of different heavy metals (copper and mercury), cationic surfactants cetylpyridinium chloride, anionic surfactant sodium dodecylbenzenesulfonate and the chemistry of the solution (pH value) on the adsorption of three selected phenolic compounds (2, 4-Dichlorophenol, 2, 4-Dinitro-phenol and 2, 4-Dimethyphenol) on sediment were studied. Results indicated that in the sediment-water system with phenolic compounds: (1) all of the data could be simulated by Freundlich equation; (2) the experiments studying pH effects showed that the adsorption capacity of 2, 4-Dichlorophenol and 2, 4-Dimethyphenol were quite potentia Hydrogenii dependent and increased with decrease in potentia Hydrogenii, while 2, 4-Dinitrophenol followed the different trend; (3) As the concentration increased from 0 to 0.2 mM for Cu 2? , the Freundlich capacity coefficient constant varied from 62.84 to 325.1 for 2, 4-Dichlorophenol, from 13.1 to 82.179 for 2, 4-Dinitrophenol and from 29.433 to 7.976 for 2, 4-Dimethyphenol, respectively. The Freundlich capacity coefficient constant of 2, 4-Dichlorophenol, 2, 4-Dinitrophenol and 2, 4-Dimethyphenol varied from 62.84 and 421.43, 13.1 and 138.1, 29.433 and 1.381, respectively, with concentration of Hg 2? increased from 0 to 0.04 mM, respectively; (4) the adsorption of 2, 4-Dichlorophenol and 2, 4-Dimethyphenol were accentuated by cetylpyridinium chloride but suppressed by sodium dodecylbenzenesulfonate, whereas the adsorption of 2, 4-Dinitrophenol on sediment was enhanced by both cationic and anionic surfactants, effects that are consistent with electrostatic and hydrophobic interactions among ionic surfactants, phenolic compounds and sediment. The results are believed to provide a useful insight into describing the transport and fate of phenolic compounds in natural environments.