摘要
基于核壳型Fe_(3)O_(4)@SiO_(2)@mSiO_(2)纳米复合材料对氨氮的吸附特性,通过Zeta电位、红外光谱、X射线衍射、带能谱的扫描电镜及X射线光电子能谱等表征手段,分析了不同pH条件下Fe_(3)O_(4)@SiO_(2)@mSiO_(2)纳米复合材料吸附氨氮前后的红外光谱、物相、微观形貌等变化,并对其氨氮吸附机制进行了探讨。结果表明:不同pH条件下,核壳型四氧化三铁复合磁性材料对氨氮的吸附效果不同,在pH=4—6条件下的吸附效果最佳,吸附量为62.74 mg/g。材料对氨氮的吸附作用由材料表面—OH的静电吸附及Si—OH和NH^(+)_(4)的离子交换吸附共同贡献。其壳层的大量Si—OH在离子交换中占主要作用,氨氮的吸附主要依靠Si—OH去质子化作用,并最终形成Si—O—N键合于材料表面,可为废水中氨氮的有效处理提供参考。
Basing on the core-shell model Fe_(3)O_(4)@SiO_(2)@mSiO_(2),the adsorption properties of the nanocomposites for ammonia/nitrogen were characterized by Zeta potential,fourier transform infrared spectroscopy,Xray diffraction,Scanning electron microscopy-Energy dispersion spectrum and X-ray photoelectron spectroscopy.The infrared spectrum,phase and micro morphology of the Fe_(3)O_(4)@SiO_(2)@mSiO_(2) before and after adsorption of ammonia/nitrogen under different pH conditions were studied,and discussed the adsorption mechanism of ammonia/nitrogen.Results shown that the adsorption effect of core-shell Fe_(3)O_(4)composite magnetic materials on ammonia/nitrogen was different under different pH conditions,and the adsorption effect was the best under pH=4—6,with the adsorption capacity of 62.74mg/g.The adsorption of ammonia/nitrogen on the material surface was contributed by the electrostatic adsorption of—OH and the ion exchange adsorption of Si—OH and NH^(+)_(4).A large amount of Si—OH in the shell played a major role in ion exchange.The adsorption of ammonia/nitrogen mainly depended on the deprotonation of Si—OH,and finally formed Si—O—N bond on the surface of the material.This study provided a reference for the effective treatment of ammonia/nitrogen in wastewater.
作者
万秋月
苏鹏鑫
霍婷婷
刘孟清
Wan Qiuyue;Su Pengxin;Huo Tingting;Liu Mengqing(School of Environment and Resource,Southwest University of Science and Technology,Mianyang 621010;Key Laboratory of Solid Waste Treatment and Resource Recycle,Ministry of Education,Mianyang 621010)
出处
《化工新型材料》
CAS
CSCD
北大核心
2021年第S01期166-171,共6页
New Chemical Materials
基金
国家自然科学基金(41872039)
四川省教育厅2020年省级大学生创新创业训练计划项目(S202010619061)
关键词
磁性四氧化三铁
氨氮
纳米材料
吸附机制
magnetic iron oxide
ammonia/nitrogen
nano material
adsorption mechanism
