Chemical-biological hybrid reactive zones and their impact on biodiversity of remediation of the nitrobenzene and aniline contaminated groundwater

The effectiveness and bio-implication of the chemical and biological hybrid reactive zones were investigated to treat contaminated water through two months simulation. The mechanism of the sequenced chemo-bio-hybrid reactive zones designed as a ZVI part for chemical treatment of nitrobenzene producing aniline and a biological membrane depredate organic pollutant using bioaugment in the bio-reactive zone. The results demonstrate that the hybrid system exhibited excellent efficiency in nitrobenzene and aniline removal, 91% (P < 0.01) and 85% (P < 0.01), respectively, for about 40 days without any extra cost. From the real time analysis of aniline and nitrobenzene, the chemo-bio reactive zone should be maintained at 40 days after the system set up. The PCR-DGGE molecular approach elucidated that the biological diversity of the membrane decreased with depth and two bioaugment bacteria could be immobilized at the membrane and have a high treatment efficacy by depleted aniline and nitrobenzene in the bio-reactive zone and form a stable community. This system indicates a higher efficacy, environmentally friendly and novel technology for remediation strategy of contaminated sites. (C) 2015 Elsevier B.V. All rights reserved.