摘要
纳米硫化亚铁(Nano-FeS)粒径小、比表面积大、反应活性高,但易团聚、易氧化的特点使其在地下水修复中的应用受到限制,通过改性可提高Nano-FeS的分散性和稳定性。本文选用羧甲基纤维素钠(CMC)及羟基铝柱撑膨润土(Alb)两种改性剂,制备了稳定型改性的CMC-FeS和负载型的Alb-FeS。分别从分散性、抗沉降性、抗氧化性、反应性和迁移性考察了两种改性Nano-FeS的性能。结果表明:Alb-FeS与CMC-FeS的分散性均较Nano-FeS得到明显改善;3d后Nano-FeS完全沉降氧化,CMC-FeS沉降3cm且开始氧化,而Alb-FeS沉降16cm却未氧化;在相同的实验条件下,Alb-FeS、Nano-FeS、CMC-FeS对Cr(Ⅵ)的去除能力从强到弱,去除率分别是85.16%、84.90%、82.78%。在粗砂、中砂与细砂介质中,3种FeS的迁移能力从强到弱依次为CMC-FeS、Alb-FeS、Nano-FeS;在3种介质中CMC-FeS的最大迁移距离分别是Nano-FeS的6.1倍、6.4倍和3.4倍,而Alb-FeS与Nano-FeS相比迁移性没有明显提高。综合考虑分散性、抗沉降性、稳定性、反应活性及迁移能力,实际应用中宜优先选择CMC-FeS作为Cr(VI)污染地下水的原位修复材料。
Nanometer iron sulfide(Nano-FeS)has small particle size,large specific surface and high reactivity,but its application in groundwater remediation is limited by its easy agglomeration and oxidation.The dispersion and stability of Nano-FeS can be improved by modification.In this study,two kinds of modifiers,sodium carboxymethyl cellulose(CMC)and pillared bentonite were used to prepare stable modified CMC-FeS and loaded Alb-FeS.The properties of the two modified Nano-FeS were investigated in terms of dispersivity,anti-sedimentation,anti-oxidation,reactivity,and migration.The results show that the dispersivity of Alb-FeS and CMC-FeS were improved obviously compared to Nano-FeS.After three days,Nano-FeS completely precipitated and oxidized,CMC-FeS precipitated 3cm and began to oxidize,while Alb-FeS precipitated 16cm without oxidation.Under the same experimental conditions,the removal rate of Alb-FeS,Nano-FeS,and CMC-FeS for Cr(Ⅵ)is 85.16%,84.90%,and 82.78%respectively,and their removal ability is Alb-FeS>Nano-FeS>CMC-FeS.The migration ability of the three kinds of FeS in the medium of coarse sand,medium sand,and fine sand is CMC-FeS>Alb-FeS>Nano-FeS.The maximum migration distance of CMC-FeS in the three media is 6.1,6.4and 3.4times of that of Nano-FeS,while the mobility of Alb-FeS is not significantly improved compared with that of Nano-FeS.Considering the dispersivity,antisedimentation,stability,reactivity,and migration,CMC-FeS should be selected as the in-situ remediation material for Cr(VI)contaminated groundwater in practical application.
作者
洪梅
任璇
杨慧萍
Hong Mei;Ren Xuan;Yang Huiping(College of New Energy and Environment,Jilin University,Changchun 130021,China;National Local Joint Engineering Laboratory of Petrochemical Pollution Site Control and Remediation Technology,Jilin University,Changchun 130021,China)
出处
《吉林大学学报（地球科学版）》
EI
CAS
CSCD
北大核心
2020年第4期1182-1188,共7页
Journal of Jilin University：Earth Science Edition
基金
国家自然科学基金项目(41530636)
水体污染控制与治理科技重大专项(2018ZX07111001)。
关键词
硫化铁
羧甲基纤维素钠
羟基铝柱撑膨润土
反应性
迁移性
iron sulfide
sodium carboxymethyl cellulose
hydroxyl aluminium pillared bentonite
reactivity
migration
