摘要
采用溶液共混法制备了壳聚糖/氧化石墨烯(CS/GO)复合材料,探讨了GO含量、pH值、CS/GO投加量、时间以及U(Ⅵ)初始浓度等对CS/GO吸附U(Ⅵ)效果的影响.试验结果表明,GO质量分数为40%,pH值为5时吸附效果最好,吸附在5 h达到平衡.准二级动力学模型和Langmuir等温吸附方程可较好地拟合其吸附过程,30℃时饱和吸附量为227.3 mg·g-1.CS/GO对U(Ⅵ)的吸附是自发的吸热反应.SEM、FTIR和XRD分析结果表明,CS/GO表面凹凸不平,羟基和氨基是U(Ⅵ)的主要结合位点.解吸试验结果表明CS/GO具有良好的重复使用性能.
The chitosan/graphene oxide composite was prepared in mix-solution. The effects of graphene oxide concentration,pH value,adsorbent dosage,contact time and initial U( Ⅵ) concentration on the adsorption behavior of chitosan/graphene oxide composite on uranium( Ⅵ) were investigated.The results show that the maximum adsorption capacity was obtained at pH of 5 with 40 wt% of GO. The adsorption equilibrium was obtained at 5 h. The adsorption process were better fitted by pseudo-second-order kinetic model and Langmuir isotherm model,respectively. The maximum adsorption capacity for U( Ⅵ) at 30 ℃ was 227.3 mg·g(-1). Thermodynamic study revealed that the adsorption of U( Ⅵ) on CS/GO was spontaneous and endothermic. SEM images illustrate that CS/GO had a rough surface and an uneven porous structure. FTIR spectra demonstrated that hydroxyl and amine groups were the main binding sites of U( Ⅵ) in CS/GO. Desorption experiments results indicate that the adsorbent had a good property for reuse.
出处
《环境科学学报》
CAS
CSCD
北大核心
2017年第4期1388-1395,共8页
Acta Scientiae Circumstantiae
基金
国家自然科学基金项目(No.11475080
11175081)
高等学校博士点基金项目(No.20134324110003)
湖南省自然科学基金项目(No.2016JJ6125)
湖南省高校创新平台项目(No.13K085
13K086)~~