Application of fly ash as an adsorbent for Estradiol in animal waste

The contamination of agricultural ground with estrogen compounds through application of animal wastes is a present concern. At the same time, current uses for waste fly ash having high carbon content are limited. To help mitigate these problems, we examine using waste fly ash as a useful adsorbent for Estradiol in pig waste digests. In this study, Estradiol was added to vials containing water and fly ash from several different power plants. After an extraction process, the amount of Estradiol in the water was measured. Commercial activated carbon was also used for comparison purposes. Vials containing varying concentrations of Estradiol and no trapping material were used as a control. The results from this study indicate that fly ash can be used as a trapping material for Estradiol in water, but that commercially available activated carbon can trap about an order of magnitude more Estradiol than the fly ash and that the effects of the fly ash matrix can both inhibit and promote the solvation of Estradiol into water depending possibly upon pH and cation concentration effects. In addition, preliminary extraction studies using pig waste digest indicate that fly ash can be used as adsorbent for Estradiol present in pig waste. •Estradiol is detectable at 2.5 ppb in pig waste digest liquid.•Fly ash waste can be used to adsorb Estradiol at approx. 0.5–1.0 μg/mg of ash.•Fly ash adsorption capability varies depending on additives and other parameters.•Some fly ashes increased the solubility of Estradiol in water.•Pig waste digest extracted with ash showed a decrease in Estradiol concentration.