典型微塑料对环丙沙星在多孔介质运移的影响

Effects of typical microplastics on migration of ciprofloxacin in porous media

为探究微塑料对抗生素在多孔介质运移的影响,本文以聚丙烯(Polypropylene,PP)作为典型微塑料,以环丙沙星(Ciprofloxacin,CIP)为典型抗生素污染物,通过CIP的吸附实验和CIP在砂柱中运移实验,研究PP对CIP在多孔介质中的运移分布的影响。结果表明,PP对CIP的吸附能力强于石英砂对CIP的吸附能力,最大Langmuir吸附能力为1.03 mg·g^(-1)。在砂柱实验中,CIP的流出浓度随PP含量的增加而降低,而流速增大时砂柱流出的CIP浓度峰值的出现时间提前。此外,当进入砂柱的CIP溶液浓度增大时,流出砂柱的CIP总量增大;溶液中增加NaCl、CaCl2和BaCl2等电解质提高离子强度,会增强CIP在砂柱中的迁移能力。研究表明,PP能显著影响CIP在多孔介质中运移的行为。

Polypropylene(PP)and ciprofloxacin(CIP)were selected as typical microplastics and antibiotics,respectively to investigate the effect of microplastics on the migration of antibiotics in porous media.Based on CIP adsorption and migration experiments conducted in a sand column,the effects of PP on the mobility of CIP in saturated porous media were explored.Results showed that the adsorption capacity of CIP on PP was stronger than the adsorption capacity of CIP on quartz sand.The maximum Langmuir adsorption capacity of CIP on PP was 1.03 mg·g^(-1).In the sand column experiments,the CIP concentration of outflow decreased with an increase in PP content,and the peak value of CIP concentration appeared earlier with an increase in flow velocity.In addition,when the CIP concentration of inflow increased,the total amount of CIP flowing out of the sand column also increased.Adding electrolytes(such as NaCl,CaCl2,and BaCl2)into the CIP solution increased the ionic strength and enhanced the mobility of CIP in the sand column.In conclusion,this study suggests that PP can significantly affect the migration behavior of CIP in porous media.