Cu（II）共存时典型磺胺类抗生素在土壤中吸附行为、机理及其表征

针对当前日趋严重的抗生素和重金属土壤复合污染问题，围绕土壤吸附过程中重金属与抗生素之间交互作用的对抗生素环境行为的影响这一科学问题，本项目拟以典型磺胺类药物--磺胺嘧啶（sulfadiazine，SD）和重金属Cu为目标污染物，采用批次平衡试验方法，重点研究：①不同pH、离子强度等环境条件下，单一及复合污染体系中SD在土壤及其有机/无机组分上的吸附特征；②不同pH、离子强度等环境条件下， Cu（II）与SD的络合特征；③借用SEM-EDS、FT-IR、NMR及Zeta电位测定等技术手段，阐释Cu（II）共存时SD在土壤中吸附作用机制；明确Cu（II）共存对SD在土壤吸附过程的影响及其作用机理。以期为土壤重金属、抗生素复合污染的生物有效性评价和环境风险预测与管理提供有效支持。

As the fast development of large-scaled livestock and poultry farming，growing attention has been paid to the co-contamination of antibiotics and heavy metals in soil. Various mechanisms play roles simultaneously for antibiotic sorption on soils. Previous studies simply emphasized mechanisms that match the increased or decreased antibiotic sorption by metal ions, without a general concept including these diverse mechanisms in their co-sorption. In this study, we chose sulfadiazine (SD) and Copper (Cu) as common representative of antibiotics and heavy metals in soils. Influences of Cu on the adsorption of SD to soil organic matter, clay and the whole soil would be investigated using a batch equilibration method. It would be to investigated the influences of pH, ionic strength, organic carbon content and complexation on the co-sorption capacity of SD and Cu(II) to selected soils. With SEM-EDS, FT-IR, NMR and Zeta sizer, we intend to summarize a general concept to understand the apparently increased and decreased antibiotic sorption by metal ions. Investigating the sorption variation of antibiotics at different conditions (such pH, CEC, and ionic strength, etc) in the presence of metal ions would provide useful information to understand the mechanisms that control their co-sorption.