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 by 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.

对重金属污染沉积物的综合修复技术已引起广泛关注。在这项研究中，对镉污染的沉积物进行了多种处理：仅硫酸盐还原菌（SRB）和SRB结合不同剂量的纳米零价铁（nZVI（0.5〜10 mg / g））。与对照相比，在所有补救措施中均发现镉的固定化是由于移动性镉的减少和更稳定的镉的增加所致。五个典型的SRB（脱硫鳞茎科，脱硫细菌科，滑膜细菌科，脱硫弧菌科和脱硫微生物科））被认为对Cd形态转化有重大影响，并且可以通过异化硫酸盐还原（DSR）使Cd稳定成硫化物沉淀。上覆水中动员指数和Cd浓度的方差分析结果均表明，与仅使用SRB的传统系统相比，采用5 mg / g和10 mg / g nZVI的综合修复系统（分别为Fe5和Fe10系统）表现出更好的固定性能。 <0.05）。可以肯定的是，nZVI可以通过在DSR期间提供电子和增强酶的活性来刺激SRB的生物固定化。XPS分析和Pourbaix图表明，在Fe10中可能会生成马基诺石，从而可能形成Cd-S-Fe。