Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, Università degli Studi di Bari Aldo Moro, Via Amendola 165/A, 70126, Bari, Italy.
Environ Sci Pollut Res Int. 2017 Aug;24(23):19159-19166. doi: 10.1007/s11356-017-9595-z. Epub 2017 Jun 29.
The present study deals with the use of low-cost plant-derived materials, namely a biochar, spent coffee grounds, spent tea leaves, and a compost humic acid, for the adsorptive removal from water of two estrogens, 4-tert-octylphenol (OP) and 17-β-estradiol (E2), and two pesticides, carbaryl and fenuron, each spiked at a concentration of 1 mg L. Kinetics and adsorption isotherms have been performed using a batch equilibrium method to measure the sorption capacities of the adsorbents towards the four molecules. Adsorption constants were calculated using the linear, Freundlich, and Langmuir models. Kinetics data obtained evidenced a rapid adsorption of each compound onto both biochar and coffee grounds with the attainment of a steady-state equilibrium in less than 4 h. Significant differences among the adsorbents and the compounds were found regarding the model and the extent of adsorption. In general, the estrogens were adsorbed more quickly and in greater amounts than the less hydrophobic pesticides, following the order: OP > E2 > carbaryl > fenuron. The ranges of Freundlich constants obtained for OP, E2, carbaryl, and fenuron onto the sorbents were 5049-2253, 3385-206, 2491-79, and 822-24 L kg, respectively. The maximum values of constants were obtained for biochar, except for OP that was more adsorbed by spent coffee grounds. Adsorption kinetic data followed a pseudo-second-order model, thus indicating the occurrence of chemical interactions between the compounds and the substrates. The remarkable sorption capacities of all adsorbents towards the four molecules suggest the valuable exploitation of these materials for decontamination purposes, such as the treatment of wastewater before a feasible recycle in soil.
本研究利用低成本的植物衍生材料，即生物炭、废咖啡渣、废茶叶和腐殖酸堆肥，从水中吸附去除两种雌激素（4-叔辛基苯酚（OP）和 17-β-雌二醇（E2））和两种农药（carbaryl 和 fenuron），每种物质的浓度均为 1mg/L。使用批量平衡法进行了动力学和吸附等温线研究，以测量吸附剂对四种分子的吸附能力。使用线性、Freundlich 和 Langmuir 模型计算了吸附常数。动力学数据表明，每种化合物都能迅速吸附到生物炭和咖啡渣上，不到 4 小时即可达到平衡状态。不同吸附剂和化合物之间在模型和吸附程度方面存在显著差异。一般来说，与疏水性较小的农药相比，雌激素被更快和更多地吸附，顺序为：OP>E2>carbaryl>fenuron。OP、E2、carbaryl 和 fenuron 在吸附剂上的 Freundlich 常数范围分别为 5049-2253、3385-206、2491-79 和 822-24 L/kg。除了废咖啡渣更能吸附 OP 外，常数的最大值均在生物炭上获得。吸附动力学数据符合准二级模型，表明化合物与底物之间发生了化学相互作用。所有吸附剂对四种分子的显著吸附能力表明，这些材料可用于去污目的，例如在可行的土壤再循环之前处理废水。
