Integrated remediation of sulfate reducing bacteria and nano zero valent iron on cadmium contaminated sediments.
J Hazard Mater
; 406: 124680, 2021 03 15.
Article
em En
| MEDLINE
| ID: mdl-33310329
ABSTRACT
Integrated-remediation technologies on heavy metal polluted sediments have received much attention. In this study, Cd contaminated sediments were treated with various conditions sulfate reducing bacteria (SRB) only and SRB combined with different dosages of nano zero valent iron (nZVI (0.5-10 mg/g)). The immobilization of Cd was found in all remediation treatments according to the decreases of mobile Cd and the increases of more stable Cd compared with control. Five typical SRBs (Desulfobulbaceae, Desulfobacteraceae, Syntrophobacteraceae, Desulfovibrionaceae and Desulfomicrobiaceae) were identified having significant influences on Cd speciation transformation and they could stabilize Cd into sulfide precipitation through dissimilatory sulfate reduction (DSR). The ANOVA results of mobilization index and Cd concentration in overlying water both demonstrated that integrated-remediation systems with 5 mg/g and 10 mg/g of nZVI (Fe5 and Fe10 systems, respectively) presented better immobilization performance than conventional SRB only system (P < 0.05). It is confirmed that nZVI could stimulate the SRB bio-immobilization possibily through providing electrons and enhancing enzyme activities during DSR. The XPS analyses and Pourbaix diagrams revealed that mackinawite may be produced in the Fe10, resulting in the possible formation of Cd-S-Fe. This study indicates that integrated-remediation of SRB and nZVI have great potential in Cd immobilization of sediments, especially with higher addition of nZVI.
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Texto completo:
1
Coleções:
01-internacional
Temas:
Agentes_cancerigenos
Base de dados:
MEDLINE
Assunto principal:
Metais Pesados
/
Deltaproteobacteria
/
Recuperação e Remediação Ambiental
Idioma:
En
Revista:
J Hazard Mater
Assunto da revista:
SAUDE AMBIENTAL
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
China