热解底泥对两种氟喹诺酮类抗生素和双酚A的吸附

Sorption of two fluoroquinolone antibiotics and bisphenol A on thermally-treated sediments

将滇池断桥底泥在不同炭化温度(200℃—500℃)下制成热解底泥,用元素分析仪表征其元素组成.以诺氟沙星(NOR)、氧氟沙星(OFL)和双酚A(BPA)为代表化合物,研究人工合成有机污染物在热解底泥上的吸附行为,从而深入了解热解底泥的吸附特性以及其施用对有机污染物的环境行为和风险的影响.结果表明,热解底泥随炭化温度的增加,芳香性升高,极性降低,阳离子交换量降低,对NOR、OFL和BPA的吸附非线性增强.热解底泥的吸附性能比原始底泥更强,随炭化温度的升高,对NOR的吸附依次减弱,对OFL的吸附变化不大,对BPA的吸附依次增强,这与热解底泥极性和阳离子交换量,以及吸附质的极性相关.在原始底泥和热解底泥上,NOR和OFL的吸附均明显强于BPA,这主要因为NOR和OFL与底泥中无机矿物组分可通过阳离子交换作用和阳离子桥接作用使其吸附强于BPA,并且NOR和OFL相比于BPA官能团多且复杂.

The sediments from Dianehi Lake were pyrolysis-treated at different pyrolytic temperatures （200-- 500 ℃ ）. These thermally-treated sediments （TTSs） were characterized for their bulk elemental composition. Norfloxacin, ofloxaein and bisphenol A were chosen as model sorbates to study the adsorption of synthetic organic contaminants on TTSs. The study was to investigate the sorption properties of TTSs and the environmental behavior and risks of organic pollutants that affected by TTSs. The increased aromaticity, decreased polarity and cation exchange capacity （CEC） , coupled with increased nonlinear sorption of NOR, OFL and BPA were observed for TFSs with increasing pyrolytic temperatures. All TTSs showed a much stronger sorption for these three sorbates than original sediment. Additionally, with increasing pyrolytic temperatures, the decreased and increased adsorptions were observed for NOR and BPA, respectively. However, OFL showed a temperature-independent adsorption on these TrSs. These results might be related to the polarity of TTSs and sorbates and CEC of TFSs. In addition, the sorption of NOR and OFL were obviously stronger than the sorption of BPA on original sediment and TTSs due to the CEC interaction, cation bridge interaction between these two antibiotics and inorganic mineral components, and abundant functional groups of OFL and NOR compared with BPA.