摘要
采用腐殖酸(HA)修饰凹凸棒(ATP)制备得到腐殖酸/凹凸棒(HA/ATP),用于去除废水中的U(VI)。通过静态吸附实验,研究了溶液初始p H、投加量、吸附时间和初始浓度对吸附的影响,并用扫描电镜(SEM),X射线能谱图(EDS),傅里叶红外光谱仪(FITR)分析吸附机理。实验结果表明,去除率随时间的增大而增大,在120 min内可以达到平衡;吸附剂投加量越大,溶液p H=6左右时越有利于U(VI)的去除;HA/ATP能多次重复使用,且经过5次吸附解吸后对U(VI)的去除率仍能达到96%。吸附过程均符合Langmuir和Frendlich等温方程。较之准一级动力学,准二级动力学模型能更好地拟合实验数据。SEM-EDS、FITR分析结果表明,U(VI)被成功地吸附到了HA/ATP的表面,吸附机理为络合作用。
Attapulgite modified by humic acid,was used to develop a novel adsorbent to remove the uranium(VI) ions from the wastewater of uranium-contained.The adsorption of U(VI) from aqueous solution to HA/ATP was studied as a function of p H,dosage,contact time,initial concentration.The adsorbent was characterized by scanning electron microscopy(SEM) with EDS analysis and Fourier transform infrared(FTIR).The results of adsorption experimental showed that the adsorption equilibrium time of U(VI) onto HA/ATP was 120 min,and high adsorbent dosages were beneficial for the adsorption.The optimum p H for the adsorption was 6.The adsorbent was suitable for repeated use(over 5 cycles) without any noticeable loss of capacity.The adsorption isotherms were simulated by the Langmuir and Freundlich very well.The rates of adsorption were found to conform to the pseudo-second-order kinetic model.The analysis of SEM-EDS and FITR before and after adsorption U(VI) was absorbed successfully onto the HA/ATP.The mechanism for the removal of U(VI) ions by HA/ATP was based on complex reaction.
出处
《环境工程学报》
CAS
CSCD
北大核心
2015年第2期705-710,共6页
Chinese Journal of Environmental Engineering
基金
国家自然科学基金资助项目(51174117)
湖南城市学院科技计划项目(2014xj08)
湖南省教育厅优秀青年项目(13B009)
