摘要
以吸附氨氮饱和的斜发沸石为研究对象,分别采用单独微波辐射及微波辅助溶剂法对其进行再生研究.研究发现,单独微波辐射再生效果较差,功率462 W,微波辐射12min,饱和沸石再次去除率为32.31%,再生率仅为44.88%;添加NaCl和NaOH混合液可以大大增强饱和沸石的再生效果,在NaCl和NaOH混合液浓度均为0.01mol/L,固液比1∶50,功率700W,微波辐射4min时,最佳去除率为71.92%,再生率接近100%.通过FTIR,SEM,EDS等测试手段对改性、吸附、再生前后的沸石分析发现,沸石在改性、吸附、再生过程中主要发生的是不同阳离子间交换过程.微波辐射加速了NH4+与Na+交换过程且加深了离子交换平衡程度,因此微波辅助溶剂法具有再生迅速、完全,多次再生效果基本不衰减的优点.
Modified clinoptilolite saturated with ammonia nitrogen was regenerated by microwave radiation alone and microwave-assisted regeneration solution, respectively. The study showed that the poor regeneration effect was obtained by microwave alone. The adsorption removal efficiency of ammonia onto spent zeolite after regeneration re- stored to 32. 31% under the conditions of the power of 462 W and microwave radiation of 12 rain, and the regeneration rate was only 44. 88%. The regeneration effect of the Saturated zeolite was highly enhanced by adding mixed solution of NaCl and NaOH. The saturated zeolite achieved the maximum removal rate of about 71.92%, and the regeneration rate was close to 100%, when it was trotted in NaCl and NaOH mixed solution concentration of 0. 01 mol/L, the rati- o of solid to liquid as 1 ： 50, the power of 700 W. and the microwave radiation of 4 min. For all the zeolites before and after modification, adsorption and regeneration were fully characterized by Fourier transform infrared spectroscopy （FTIR）, scanning electron microscopy （SEM） and energy-dispersive X-ray spectroscopy （EDS） technique. The re- sults demonstrated that zeolites mainly exhibited cation exchange in the process of modification, adsorption and regen- eratior. Microwave radiation accelerated the exchange process and deepened the ion exchange equilibrium degree be-tween NH4 ＋ and Na＋ , which contributes to the NH4 ＋ desorption from zeolite framework fast and completely.
出处
《湖南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2016年第12期140-147,共8页
Journal of Hunan University:Natural Sciences
基金
国家自然科学基金资助项目(51174017)~~
关键词
氨氮
饱和沸石
微波
再生
离子交换
ammonia nitrogen
saturated zeolite
microwave
regeneration
ion exchange
