中文摘要：

环境中抗生素与重金属的共存会使各自在土壤中的迁移转化和生态效应变得更为复杂,为了准确评估磺胺二甲基嘧啶（SMT）与重金属镉复合污染下的环境风险,采用紫外光谱法,研究了中性条件下磺胺二甲基嘧啶与镉的络合特性;采用批量振荡吸附平衡法,研究了SMT存在的条件下针铁矿对镉的吸附特性.结果表明：SMT与镉有一定的络合能力,络合常数log K值为-3.31;针铁矿对SMT和镉都有一定的吸附作用;在SMT存在条件下,针铁矿对镉的吸附容量明显增强,这可能是由于SMT改变了针铁矿表面带电情况,红外结果表明在吸附过程中形成了针铁矿-SMT-镉三元络合物.因此,在评估抗生素与重金属复合污染的环境影响时,需要考虑到污染物之间的协同效应.

英文摘要：

The coexistence of antibiotics and heavy metals might lead to complicated transport behaviors and ecological effects in the environment. UV-Vis method was employed to investigate the complexation between sulfamethazine（ SMT） and Cd（ II） at neutral condition. Results showed that SMT exhibited certain complexation ability to cadmium and the binding constant（ log K） was about-3.31. The results of batch adsorption equilibrium experiments showed that both of SMT and Cd^2＋could be adsorbed on the surface of goethite and the sorption capacity of Cd2＋on the goethite could be enhanced by SMT in a certain concentration range. It might be due to the fact that adsorbed SMT could neutralize the positive charge of goethite. FTIR results showed the specific ternary complex of goethite-SMT-Cd^2＋might be formed on the surface. The synergic adsorption of co-contaminants should be considered to assess the risk of antibiotic drugs and heavy metal pollution in the environment.