摘要
为了探究水体中Pb^(2+)有效去除方法,以黄磷渣为原料实现二氧化硅的制备、纯化及表征,以其为媒介探究不同因素下对Pb^(2+)的吸附性能。结果表明:SiO_(2)表面成功接枝KH570,传质动力随吸附时间的增加逐渐减弱,吸附缓慢,吸附容量在30 min时饱和达到9.51 mg/g;60 min后发生解析,导致吸附容量下降至9.38 mg/g。随着温度升高和溶液Pb^(2+)浓度的增大,活性位点与Pb^(2+)有效碰撞的机率增大,吸附容量达到12.3 mg/g;随着pH值升高吸附容量增大。笔者采用Langmuir和Freundlich模型探索吸附剂对Pb^(2+)的吸附行为发现:Langmuir模型等温吸附适合描述吸附剂对Pb^(2+)的吸附行为,且SiO_(2)对Pb^(2+)的吸附符合二级动力学行为。
Explore the adsorption performance of modified silica prepared by yellow phosphorus slag on lead ions.Silica was prepared and purified from yellow phosphorus slag by nitric acid leaching and alkali precipitation.Use alkyl coupling agent KH570 for wet modification.The adsorbents were characterized by SEM(scanning electron microscope)and FTIR(infrared spectrometer).The adsorption performance of adsorbent for Pb^(2+)under different factors was explored.The results showed that KH570 was successfully grafted on the surface of silica.With the increase of adsorption time,the mass transfer power was weakened and the adsorption rate was slow.After 30 minutes,the adsorption capacity reached saturation(9.51 mg/g),and then tended to be stable.After 60 minutes,desorption occurred,resulting in a slight decrease in adsorption capacity(9.38 mg/g).With the increase of temperature and initial Pb^(2+)content,the collision probability between active sites on the surface of the adsorbent and Pb^(2+)increases,and the mass transfer power increases,resulting in an extreme adsorption capacity of 12.3 mg/g.When the Pb^(2+)concentration was between 20 and 30 mg/L,the adsorption capacity of adsorbent for Pb^(2+)changed little.The activity and morphology of the adsorbent were affected by the pH of the solution,the results showed that the adsorption capacity of the adsorbent for Pb^(2+)increased with the increase of pH in the acidic environment.Langmuir and Freundlich models were used to investigate the adsorption behavior of Pb^(2+)on the adsorbent.The results showed that the isothermal adsorption of Langmuir model was suitable for describing the adsorption behavior of adsorbent for Pb^(2+),and the adsorption behavior conformed to the second-order kinetic equation.
作者
刘慧娟
Liu Huijuan(Key Laboratory of Environmental Pollution Monitoring and Disease Control,Ministry of Education,Guizhou Medical University,Guiyang 550025,China)
出处
《山东化工》
CAS
2023年第14期1-3,6,共4页
Shandong Chemical Industry
基金
贵州省科技计划项目:黔科合基础-ZK[2022]一般365
贵州医科大学高层次人才启动基金,校博合J字[2021]007号
中药饮片灵芝孢子粉关键技术研究与应用,筑科合同[2020]-18-6号。
作者简介
刘慧娟,女,讲师,研究方向:典型污染物毒性损害与修复。
