CAJ | 학술논문

采用自动电位滴定法,研究了水环境中4种常见的重金属离子Cu2+、Pb2+、Zn2+、Cd2+与环丙沙星、磺胺甲基嘧啶和全氟辛酸的络合效应.测定了3种有机物与4种金属离子的络合常数logK值,计算了各种络合物在不同pH值下的形态分布.结果表明,Cu2+与环丙沙星能形成较为稳定的络合物 Cu(cip±)2+、Cu(cip±)22+、Cu(cip-·cip±)+,其络合能力要远强于 Pb2+、Zn2+、Cd2+,前者形成的络合常数要比后三者高出3个数量级.4种金属离子与磺胺甲基嘧啶均有一定的络合能力,但稳定常数差别不大.全氟辛酸分子中由于带有较多的电负性强的 F,表现出强酸的性质,与4种金属离子未见明显的络合作用.
채용자동전위적정법,연구료수배경중4충상견적중금속리자Cu2+、Pb2+、Zn2+、Cd2+여배병사성、광알갑기밀정화전불신산적락합효응.측정료3충유궤물여4충금속리자적락합상수logK치,계산료각충락합물재불동pH치하적형태분포.결과표명,Cu2+여배병사성능형성교위은정적락합물 Cu(cip±)2+、Cu(cip±)22+、Cu(cip-·cip±)+,기락합능력요원강우 Pb2+、Zn2+、Cd2+,전자형성적락합상수요비후삼자고출3개수량급.4충금속리자여광알갑기밀정균유일정적락합능력,단은정상수차별불대.전불신산분자중유우대유교다적전부성강적 F,표현출강산적성질,여4충금속리자미견명현적락합작용.
The complexation effect between ciprofloxacin (CIP), sulfamerazine (SMR) and perfluorooctanoic acid (PFOA) and typical heavy metal cations (Cu2+, Pb2+, Zn2+, Cd2+) was investigated by automatic potentiometric titration method and the titration curves were used to derive the binding constants logK between the metals and ligands. Aqueous speciation distribution of various metallic complexes at different pH values were then calculated. Results showed that Cu2+ could form stable complexes Cu(cip±)2+、Cu(cip±)22+、Cu(cip-·cip±)+with CIP and the binding affinity of Cu2+ was much stronger than that of Pb2+, Zn2+and Cd2+. Four metal cations all could complex with SMR, while with little difference. Since PFOA molecule carried a lot of F atoms, it behaved like strong acid and no significant complexation effect was observed between PFOA and four metal ions.