废偕胺肟型螯合树脂再生工艺及吸附性能研究

为了解决废弃螯合吸附树脂堆积对环境造成污染,在参考了原树脂合成路线的基础上,设计出了资源化处理该树脂的方法。在二乙胺溶剂中,以废偕胺肟型螯合树脂为原料,加入羟胺试剂,使废树脂发生偕胺肟化反应改性为偕胺肟基聚丙烯腈-二乙烯基苯,实现了废树脂的再生。探讨了废螯合树脂改性工艺及吸附性能,在实验中单因素考察了反应温度、反应时间、二乙胺浓度、盐酸羟胺浓度以及NaOH浓度等因素对偕胺肟化反应效率的影响,同时对树脂及二乙胺溶液进行循环使用。结果表明,二乙胺浓度为70%,盐酸羟胺浓度为1.2mol/L,NaOH浓度为2mol/L,反应温度为50℃,反应时间为2h时达到最佳再生综合效能。以Cu(Ⅱ)离子进行吸附效率测试,有效地恢复该种树脂的吸附能力的90%。树脂循环使用四次之后,吸附效率仍能达到60%。傅里叶变换红外光谱(FT-IR)对螯合树脂表征表明,腈基转化成了偕胺肟基团。在废树脂再生的反应过程中,二乙胺溶剂表现为激活剂的作用。

Regeneration Technology and Adsorption Capacity of Waste Chelating Resin with Amidoxime Group

To solve the environment pollution caused by accumulation of discarded waste chelating resin,a method for resin resource was designed with reference of the synthetic route of resin. Under a certain concentrations of diethylamine,waste chelating resin was modified into a AN-DVB containing amidoxime group by adding hydroxylamine,resulting from that nitrile group was transformed into amidoxime group. Experimental conditions were discussed. Effects of reaction time,reaction temperature,concentration of diethylamine,HCl·NH2OH concentration and NaOH concentration on the ratio of transformed into amidoxime group were investigated,the recycling use of resin and diethylamine were studied. Results showed that the maximum adsorption of chelating resin can achieve 90% for the adsorption of metal ion Cu (II) when concentration of diethylamine was 70% ,NaOH concentration was 2mol/L,HCl·NH2OH concentration was 1.2mol/L,reaction temperature was 50℃,and reaction time was 2h. After recycling use of the resin for 4 times,the adsorption of chelating resin was still more than 60%. The chelating resin was characterized by Fourier transform infrared spectroscopy (FT-IR). In the process of reaction,the diethylamine was used as activator.