摘要
采用自制桉树遗态羟基磷灰石/碳复合材料(PBGC-HAP/C)为吸附剂,溶液体系pH值、Cu(Ⅱ)初始浓度和材料粒径为影响因素,研究了PBGC-HAP/C吸附Cu(Ⅱ)的具体特征与机制.结果表明,当溶液为弱酸性时(pH=5),吸附效果最佳;增大反应体系初始浓度不利于吸附效果的提升;减小吸附剂粒径对吸附有促进作用.准二级动力学可准确描述该吸附过程,计算获取的吸附容量0.99、1.93和4.03 mg·g-1与实验值0.99、1.93和4.05 mg·g^(-1)高度接近;Langmuir模型很好地拟合了吸附过程,表明吸附是单层吸附,温度升高有利于吸附进行;热力学实验结果ΔGθ<0、ΔSθ>0和ΔHθ>0,显示该吸附过程是自发、熵增的吸热过程.SEM、EDS、XRD和FTIR对吸附前后材料表征分析可知PBGC-HAP/C表面的含氧官能团与Cu(Ⅱ)发生的化学络合反应为主要净化机制,同时伴随着物理吸附、静电吸附和离子交换作用.
The specific characteristics and mechanism of adsorption of Cu（ Ⅱ） were studied by using HAP / C composite（ PBGC-HAP /C） as adsorbent,and using pH value of the solution system,initial concentration of Cu（ Ⅱ） and particle size of the material as influential factors. The results showed that when the solution was weak acid（ pH = 5）,the adsorption effect was the best; the increase of the initial concentration of the reaction system was not conducive to the enhancement of the adsorption effect; and the decrease of the particle size of the adsorbent facilitated the adsorption process. The pseudo-second-order kinetic model could accurately describe the adsorption process,and the calculated adsorption capacity（ 0. 99,1. 93,4. 03 mg·g-1） was close to the experimental measured values（ 0. 99,1. 93,4. 05 mg·g- 1）; Langmuir model could fit the adsorption process very well,which indicated that adsorption was monolayer adsorption and the increase of temperature was conducive to adsorption. The thermodynamics test results of ΔGθ〈 0,ΔSθ〉0 and ΔHθ〉 0 showed that the adsorption process was endothermic and spontaneous. Through comparative analysis of the SEM,EDS,XRD and FTIR of materials before and after adsorption,the results indicated that the chemical complexation reaction of Cu（ Ⅱ） with the oxygen functional groups on the surface of PBGC-HAP / C was the main purification mechanism,which was accompanied with physical adsorption,electrostatic adsorption and ion exchange.
作者
李超
朱宗强
曹爽
朱义年
谭笑
丁慧
LI Chao ZHU Zong-qiang CAO Shuang ZHU Yi-nian TAN Xiao DING Hui(Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin 541004, China Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China Henan Electric Power Survey ＆ Design Institute, Zhengzhou 450007, China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2017年第3期1074-1083,共10页
Environmental Science
基金
国家自然科学基金项目(NSFC41263009)
广西自然科学基金项目(2014GXNSFBA118054)
广西科学研究与技术开发计划项目(桂科攻14124004-3-3)
广西高校科学技术研究重点项目(KY2015ZD053)
广西矿冶与环境科学实验中心项目(KH2012ZD004)
广西高等学校高水平创新团队及卓越学者计划项目(002401013001)
国家自然科学基金重点项目(51638006)
