摘要
利用植物提取液绿色合成的纳米铁,具有绿色环保、成本低廉等优点。基于此,通过对9种植物叶片提取液进行抗氧化活性的分析,筛选出了抗氧化活性较高的3种植物提取液,且利用其制备了纳米零价铁,分别为绿茶纳米铁(GT-nZⅥ)、石榴叶纳米铁(PG-nZⅥ)和红茶纳米铁(BT-nZⅥ)。通过沉降实验、UV-vis、SEM、FT-IR、XRD、TG等分析方法对绿色纳米铁进行了悬浮稳定性和物理化学性质的表征分析。最后,选择Cr(Ⅵ)作为目标污染物,考察了绿色纳米铁的反应活性。结果表明:GT-nZⅥ粒径最小(约88 nm),悬浮稳定性优于另外2种绿色纳米铁,且表面包裹了更多含C=C基团的有机物;在相同的反应条件下,反应开始的1 h内GT-nZⅥ对Cr(Ⅵ)的去除效果最好;借助双室一级动力学模型拟合去除Cr(Ⅵ)反应过程发现,体系中还原反应占主导作用。对不同植物提取液合成纳米铁的理化性质及其去除Cr(Ⅵ)机理的研究,将有助于增加对绿色纳米铁环境功效的理解,对于发展绿色纳米铁修复地下水污染技术具有重要的参考价值。
Plant extract based green synthesis of nano-iron particles has the advantages of low cost and environmental friendly.In this study,the oxidation resistance properties of nine typical plant leaves extracts were compared and three of them with higher antioxidation activities were chosen for the synthesis of nanozero-iron products:green tea nano-zero-valent iron(GT-nZⅥ),pomegranate leaf nano-zero-valent iron(PGnZⅥ)and black tea nano-zero-valent iron(BT-nZⅥ).The synthesized nanoparticles were characterized by UVvis,SEM,FT-IR,XRD and TG for suspension stability and physicochemical properties.At last,Cr(Ⅵ)was selected as the model pollution compound for the reaction activity of green nano-zero-iron.The experimental results showed that the GT-nZⅥ had the smallest particle size(about 88 nm)and the best aqueous suspension stability than the other two green nano-irons.The surface of GT-nZⅥ was covered with more organic functional groups,such as C=C group.Under the same condition,GT-nZⅥ had the best Cr(Ⅵ)removal performance within first hour of reaction.The fitting results of the kinetic process of Cr(Ⅵ)removal by the two-compartment first order kinetic model indicated that the reduction reaction was dominant during the reaction.The study on the physicochemical properties of nano iron synthesized from different plant extracts and its removal mechanism of Cr(Ⅵ)will help to facilitates the understanding of the environmental remediation potential of nano iron particles,and provide an important reference for the development of green nano iron remediation technology of groundwater pollution.
作者
王嘉瑜
蒲生彦
侯国庆
WANG Jiayu;PU Shengyan;HOU Guoqing(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China;State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil&Water Pollution,Chengdu University of Technology,Chengdu 610059,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2020年第9期2537-2547,共11页
Chinese Journal of Environmental Engineering
基金
国家水体污染控制与治理科技重大专项(2018ZX07109)
国家自然科学基金资助项目(41772264)。
关键词
绿色合成
纳米铁
植物提取液
六价铬
地下水污染
green synthesis
nZⅥ
plant extract
hexavalent chromium
groundwater contamination
