摘要
为快速降低高NH_(4)+水源中的NH_(4)+浓度,便于后续生化工艺处理,本研究选用天然沸石作为吸附剂,并考察了影响天然沸石对高浓度NH_(4)+吸附性能的因素;通过研究天然沸石对高浓度NH_(4)+的吸附动力学、等温线和热力学特性,并结合分子动力学模拟,探究了天然沸石对高浓度NH_(4)+的吸附机理。结果表明,当天然沸石投加量为50 g/L、NH_(4)^(+)-N初始质量浓度为4000 mg/L、温度为35℃、吸附时间为3 h时,天然沸石对NH_(4)^(+)-N的吸附量可达26.94 mg/g。吸附动力学和等温线分析表明,天然沸石对高浓度NH_(4)+的吸附过程更适合用准二级动力学模型和Freundlich模型描述。理论计算和红外光谱表征佐证了氢键和化学吸附作用的存在。天然沸石吸附高浓度NH_(4)+受多重作用共同影响,主要由离子交换过程、静电引力和化学吸附作用协同促进,同时氢键也对天然沸石的高效吸附起辅助作用。本研究对丰富沸石吸附水体中NH_(4)+的吸附机理内容具有重要理论意义。
In order to rapidly reduce the NH_(4)+concentration in the water source with high NH_(4)+,and facilitate subse⁃quent biochemical process treatment,the natural zeolite was selected as the adsorbent in this study,and the factors affecting the adsorption performance of the natural zeolite on high concentration of NH_(4)+was investigated.The ad⁃sorption mechanism of high concentration NH_(4)+by natural zeolite was investigated through adsorption kinetics,iso⁃therm and thermodynamic characteristics,together with molecular dynamics simulation.The results showed that the adsorption capacity of NH_(4)^(+)-N was up to 26.94 mg/g when the condition were of the natural zeolite dosage 50 g/L,the initial NH_(4)^(+)-N mass concentration 4000 mg/L,temperature 35℃,adsorption time 3 h.The adsorption kinetics and isotherm analysis showed that the adsorption process of natural zeolite on high concentration NH_(4)+was more suitable to be described by pseudo-second-order kinetics and Freundlich model.The results of theoretical computa⁃tion and FT-IR spectra confirmed the existence of hydrogen bonds and chemical adsorption.The adsorption of high concentration NH_(4)+by natural zeolite was affected by multiple interactions,including the ion exchange process,elec⁃trostatic attraction and chemical adsorption.At the same time,the hydrogen bond also played an auxiliary role in the efficient adsorption of natural zeolite.This study had important theoretical significance for enriching and expanding the content about the adsorption mechanism investigation of high concentration NH_(4)+using natural zeolite as the ad⁃sorbent in water.
作者
刘磐
刘永军
刘兴社
杨璐
LIU Pan;LIU Yongjun;LIU Xingshe;YANG Lu(School of Environmental and Municipal Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Xi’an Aeronautical Polytechnic Institute,Xi’an 710089,China)
出处
《工业水处理》
CAS
CSCD
北大核心
2023年第2期68-75,共8页
Industrial Water Treatment
基金
国家自然科学基金项目(51978559)
陕西省重点研发项目(2019ZDLSF-06)。
