摘要
采用液相还原法制得的纳米零价铁(nZVI),负载于铝基金属有机框架上制成复合材料(nZVI@Al-MOF),用于去除水中的NO_(3)^(-)-N。考察初始pH、nZVI@Al-MOF投加量、温度和共存离子等因素对去除NO_(3)^(-)-N的影响。结果表明,在pH为3.0~11.0的研究范围内,nZVI@Al-MOF去除NO_(3)^(-)-N几乎不受pH的影响。NO_(3)^(-)-N初始质量浓度20 mg/L、温度298 K,nZVI@Al-MOF投加量2.0 g/L时,反应180 min,初始pH为3.0、5.0、7.0、9.0、11.0时,NO_(3)^(-)-N去除率分别可达96.8%、97.1%、97.8%、99.8%、98.1%,几乎所有的NO_(3)^(-)-N被还原为NH_(4)^(+)-N,去除效果极佳且表现稳定。伪二级吸附动力学模型极好描述了(R~2=0.999 6~0.999 9)nZVI@Al-MOF吸附还原NO_(3)^(-)-N的行为,其等温吸附过程符合Freundlich模型,表明吸附为多层化学吸附。热力学结果显示,吸附反应是自发吸热的过程。SEM和FTIR的表征结果显示,nZVI成功负载于Al-MOF上,nZVI@Al-MOF对NO_(3)^(-)-N的去除主要是吸附和还原作用的结果。
Nano-zero valent iron (nZVI) was obtained by liquid phase reduction method on an aluminum-based metal-organic framework (MOF) to make a composite material (nZVI@Al-MOF).And the nZVI@Al-MOF was used to remove NO_3~--N from water.The effects of initial pH,dosage of nZVI@Al-MOF,temperature and coexisting ions were investigated.The results showed that the removal of NO_3~--N by nZVI@Al-MOF was almost unaffected by pH within the range of 3.0~11.0.When the initial concentration of NO_3~--N is 20 mg/L,the temperature is 298 K,the dosage of nZVI@AlMOF is 2.0 g/L,the reaction lasts for 360 min,initial pH is 3.0,5.0,7.0,9.0,and 11.0,the NO_3~--N removal rates can reach 96.8%,97.1%,97.8%,99.8%,and 98.13%,and almost all of NO_3~--N was reduced to NH_4~+-N with the excellent removal efficiency and stable performance.The pseudo-second-order adsorption kinetic model well describes the adsorption and reduction behavior of NO_3~--N by the nZVI@Al-MOF (R~2=0.999 6~0.999 9).Its isothermal adsorption process conforms to the Freundlich model,indicating that the adsorption is a multilayer chemical adsorption.The characterization results of SEM and FTIR showed that the nZVI was successfully loaded on Al-MOF,and the removal of NO_3~--N by the nZVI@Al-MOF was mainly attributed to the adsorption and reduction.
作者
孟家琪
郭波
金史怡
邢海双
陈越
MENG Jiaqi;GUO Bo;JIN Shiyi;XING Haishuang;CHEN Yue(College of Environmental Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China)
出处
《水处理技术》
CAS
CSCD
北大核心
2024年第5期60-66,共7页
Technology of Water Treatment
基金
山西省专利转化专项计划项目(202202055)
