摘要
采用酸刻蚀及氧化处理技术制备了氧化氮化碳(OCN)纳米材料,探究了OCN对水中U(Ⅵ)的吸附-解吸性能。考察了溶液pH、温度、OCN投加量、反应时间、U(Ⅵ)初始浓度等因素对OCN吸附U(Ⅵ)的影响,并探讨了吸附机制。结果表明:OCN对U(Ⅵ)有良好的吸附效果,在pH=5、30℃、U(Ⅵ)的初始质量浓度为10 mg/L,OCN的投加量为200 mg/L时,OCN对U(Ⅵ)吸附率达98.9%,比未改性的石墨相氮化碳(g-C3N4)吸附U(Ⅵ)的性能提高了约42.82%,吸附反应在10 min即到达吸附平衡。pH是影响OCN吸附U(Ⅵ)的重要影响因素,温度等因素对U(Ⅵ)的吸附影响较小。拟二级动力学方程和Langmuir模型很好地拟合了吸附过程,OCN对U(Ⅵ)的吸附过程为自发的吸热过程。吸附解吸实验结果表明,OCN具有良好的重复利用性。
Oxidized graphitic carbon nitride(OCN)nanomaterials were successfully synthesized by a acid etching and oxidation method.The adsorption-desorption performance of OCN nanomaterials for U(Ⅵ)was investigated.The effects of pH of solution,temperature,OCN dosage,contacting time and initial concentration of U(Ⅵ)were investigated by static batch experiments,and the adsorption mechanism was discussed.The experiments indicated that OCN exhibited superior adsorption performance to U(Ⅵ).Under the conditions of pH 5,adsorption temperature 30℃,initial concentration of U(Ⅵ)10 mg/L,and OCN dosage 200 mg/L,the adsorption efficiency of OCN to U(Ⅵ)reached 98.9%,which was improved by about42.82%compared with the unmodified graphite nitride carbon(g-C3N4),and the adsorption equilibrium was reached at 10 min.The adsorption process was greatly affected by the pH of solution and less affected by other factors such as temperature.The adsorption process was fitted well the pseudo-second-order kinetic equation and Langmuir model,and the adsorption process of OCN to U(Ⅵ)was spontaneous endothermic process.The results of adsorption desorption experiments revealed that OCN had good reusability.
作者
刘金香
陈子庚
谢水波
刘迎九
俞坤
LIU Jin-xiang;CHEN Zi-geng;XIE Shui-bo;LIU Ying-jiu;YU Kun(Hunan Provincial Key Laboratory of Pollution Control and Resources Technology,University of SouthChina,Hengyang 421001,Hunan,China;Key Discipline Laboratory for National Defence for Biotechnology inUranium Mining and Hydrometallurgy,University of South China,Hengyang 421001,Hunan,China)
出处
《精细化工》
EI
CAS
CSCD
北大核心
2019年第7期1446-1452,1458,共8页
Fine Chemicals
基金
国家自然科学基金(11475080)
南华大学博士科研启动基金项目(2016XQD06)
南华大学研究生科学基金项目(2018KYY104)
关键词
氮化碳
氧化
U(Ⅵ)
吸附
水处理技术
g-C3N4
oxidation
U(Ⅵ)
adsorption
water treatment technology
