The impact of iron nanoparticles on technetium-contaminated groundwater and sediment microbial communities

JOURNAL OF HAZARDOUS MATERIALS

卷:364

Article

Newsome, Laura^1,2  Morris, Katherine^1,2  Cleary, Adrian^1,2  Masters-Waage, Nicholas Karl^1,2  Boothman, Christopher^1,2  Joshi, Nimisha^1,2  Atherton, Nick³  Lloyd, Jonathan R.^1,2 

[1] Univ Manchester, Sch Earth & Environm Sci, Williamson Res Ctr, Manchester M13 9PL, Lancs, England

[2] Univ Manchester, Sch Earth & Environm Sci, Res Ctr Radwaste Disposal, Manchester M13 9PL, Lancs, England

[3] Sellafield Ltd Land Qual, Seascale CA20 1PG, Cumbria, England

关键词: Bioremediation;    Nuclear;    Nanotechnology;    Biogeochemistry;    Microbial community;   

DOI  :  10.1016/j.jhazmat.2018.10.008

来源: Elsevier

【 摘 要 】

Iron nanoparticles are a promising new technology to treat contaminated groundwater, particularly as they can be engineered to optimise their transport properties. Technetium is a common contaminant -at nuclear sites and can be reductively scavenged from groundwater by iron(II). Here we investigated the potential for a range of optimised iron nanoparticles to remove technetium from contaminated groundwater, and groundwater/sediment systems. Nano zero-valent iron and Carbo-iron stimulated the development of anoxic conditions while generating Fe(II) which reduced soluble Tc(VII) to sparingly soluble Tc(IV). Similar results were observed for Fe (II)-bearing biomagnetite, albeit at a slower rate. Tc(VII) remained in solution in the presence of the Fe(III) mineral nano-goethite, until acetate was added to stimulate microbial Fe(III)-reduction after which Tc(VII) concentrations decreased concomitant with Fe(II) ingrowth. The addition of iron nanoparticles to sediment microcosms caused an increase in the relative abundance of Firmicutes, consistent with fermentative/anoxic metabolisms. Residual bacteria from the synthesis of the biomagnetite nanoparticles were out-competed by the sediment microbial community. Overall the results showed that iron nanoparticles were highly effective in removing Tc(VII) from groundwater in sediment systems, and generated sustained anoxic conditions via the stimulation of beneficial microbial processes including Fe(III)-reduction and sulfate reduction.

【 授权许可】

Free