利用电纺丝技术制备了聚丙烯腈纳米纤维无纺布,然后在水溶液原位偕胺肟化得到偕胺肟化聚丙烯腈纳米纤维,该纳米纤维可用于吸附再生含金属离子废水.采用氯化铜溶液模拟含金属离子废水,探讨不同肟化率的偕胺肟化纳米纤维对铜离子的吸附效果；发现肟化率78.8％的偕胺肟化纳米纤维的吸附能力最好,利用Langmuir吸附方程得到最大吸附值为56.5 mg/g,同时吸附后可将含铜废水浓度从100 mg/L降至13μg/L,远远低于国标GB8978-1996规定的铜排放的一级标准(总铜浓度＜0.5 mg/L).吸附铜离子的纳米纤维在1 mol/L稀硝酸中,100 min后铜离子的解吸附率超过98％.经4次吸附-解吸附循环后,偕胺肟化纳米纤维的吸附能力仍能达到首次吸附最大吸附值的50％以上,表明偕胺肟化纳米纤维具有一定的循环再生能力.%Polyacrylonitrile non-woven mat with nanofibers was fabricated by electrospinning,and amidoxime modified polyacrylonitrile nanofibers which can be used to absorb and recover metal ion from metal ion containing waste water were prepared via in situ amidoxime modification in aqueous solution.The copper chloride solution was used to simulate metal ion containing waste water and the adsorption behavior of amidoxime modified polyacrylonitrile nanofibers with different oximation time was evaluated.The nanofibers after 8 h oximation were calculated to possess the highest adsorption capacity of 56.5 mg/g according to Langmuir equation,and the concentration of metal ion containing waste water can be reduced from 100 mg/L to 13 μg/L after treating with amidoxime nanofibers,which not only reach but also highly exceed the national standard for metal ion containing waste water treatment(＜0.5 mg/L,GB8978-1996).On the other side,the metal ions were desorbed from nanofibers in dilute acid solution,and the desorption ratio was more than 98％ after 100 min desorption in 1 mol/L HNO3 solution.Furthermore,the amidoxime nanofibers remain more than 50％ of its original adsorption capacity after four adsorption-desorption circles,which showed relative recycling ability of amidoxime nanofiber.
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