改性纳米零价铁的制备及其去除水中的四环素

Preparation of modified nanoscale zero-valent iron particles and its application in removal of tetracycline from wastewater

对聚乙烯吡咯烷酮(PVP-K30)改性纳米零价铁(NZVI)用于水中四环素(TC)的去除进行研究。通过XRD,TEM和BET对改性后的纳米铁性能进行表征。探讨不同反应条件对PVP-NZVI去除四环素的影响。实验结果表明,在制备过程中添加PVP-K30改性剂可以明显减小纳米铁颗粒粒径,增大比表面积,提高TC的去除率。当初始TC溶液pH为6.5,PVP-NZVI投加量为0.1 g/L,反应240 min时,TC的去除率达98.4%,表明PVP-NZVI能有效去除水中的TC。初始pH值为酸性、偏中性的条件下TC的去除效果较碱性条件下好。同时,对反应产物进行了LC-MS分析,发现有3种主要的还原产物产生,推测出其可能的化学结构。并且对PVP-NZVI去除TC的机理进行了初步探讨。

Nanoscale zerovalent iron（NZVI） modified by polyvinylpyrrolidone（PVP-K30） was applied to remove tetracycline（TC） from aqueous solutions.The synthesized polyvinylpyrrolidone modified nanoscale zerovalent iron（PVP-NZVI） was characterized by XRD,TEM and BET. The removal efficiency of TC by PVP-NZVI under different reaction conditions were investigated. Experimental results showed that the adding of PVP-K30 in preparation can decrease the particle size,increase the specific surface area and improve the efficiency of removal obviously. In the experiment,PVP-NZVI possessed good removal efficiency of TC, the TC removal efficiency could reach 98.4% after 240 min at the dosage adding of 0.1 g/L PVP-NZVI at pH 6.5.The concentration decrease of TC is more effective in acidic and neutral pH.LC-MS spectra experiment was performed to determinate TC fragmentation pattern in the perspective of degradation product study and found out three main degradation products.In addition,the removal mechanisms were also speculated.