AWWA ACE58195 ✓ Most Recent

The adsorption of three estrogenic compounds (bisphenol A (BPA), 17-estradiol (E2), and 17+/--ethynyl estradiol (EE2)) on powdered activated carbons (PACs) was investigated. Without preconcentration, method detection limits (MDL) using high performance liquid chromatography (HPLC) with fluorescence detection at an excitation wavelength of 280 nm and an emission wavelength of 310 were 201 ng/L, 313 ng/L, and 283 ng/L for BPA, E2, and EE2, respectively. In addition, the adsorption of E2 was measured by liquid scintillation counting using tritium (3H) labeled E2 in the ng/L range. The order of compound removal by PAC (E2>EE2>BPA) corresponded with logKow values for the compounds (4.0, 3.7, 3.3, respectively). Kinetic and PAC dose-response experiments were conducted with the two PACs. Increasing contact time and PAC dose improved compound removal. Freundlich isotherm parameters were fit to the experimental data. This study confirms that PAC treatment is feasible for >99 % removal of three estrogenic compounds from raw drinking waters that may be at risk for containing such compounds. In addition, the removal percentage of E2 occurring at ng/L levels by PAC was independent of their initial concentration. Includes 20 references, tables, figure. See more