天然膨润土负载纳米铁的制备及其对阿莫西林的降解性能

Preparation of nanoscale zero-valent iron loaded bentonite and degradation of amoxicillin

采用液相还原法制备膨润土负载纳米铁(B-nZVI)用于降解水体中的阿莫西林(AMX).通过SEM、XRD、FT-IR、BET等表征手段,对其微观结构和B-nZVI与阿莫西林反应前后进行了表征,还进行了其对阿莫西林的降解实验.研究表明,制成的B-nZVI材料中的纳米铁多数以30～90nm球形颗粒为主,均匀地分散在膨润土中,从而提高了纳米铁的反应活性,对阿莫西林的去除率要比单独使用纳米铁(nZVI)高,其降解过程符合表观一级反应动力学.基于表征和降解动力学的依据,B-nZVI对阿莫西林的可能降解机理是内酰胺键被零价铁还原作用而打开.

Bentonite supported nanoscale zero-valent iorn（B-nZVI） was prepared by chemical reduction in aqueous solution and used to degrade amoxicillin.In addtion,SEM,XRD,FT-IR,BET and were used to characterize the changes in B-nZVI before and after reacting with amoxicillin.The results showed that most of the nano-iron in the products is between 30 and 90 nm dispersion well on the bentonite,reduction in aggregation and consequently improvement in the reactivity of B-nZVI.The degradation of amoxicillin was found to be fitted well-first-order kenitic model.On the basis of these results,the degradation mechanism of AMX could be attribute that ？-lactam ring was opened by B-nZVI and finally this ring was broken.