Remediation of Cr(VI) from chromium slag by biocementation

TY - JOUR

T1 - Remediation of Cr(VI) from chromium slag by biocementation

AU - Achal, Varenyam

AU - Pan, Xiangliang

AU - Lee, Duu Jong

AU - Kumari, Deepika

AU - Zhang, Daoyong

N1 - Funding Information: This work was supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX2-YW-335), Program of 100 Distinguished Young Scientists of the Chinese Academy of Sciences, National Natural Science Foundation of China (U1120302, 41250110527, 41072195 and 40872169), and the Chinese Academy of Sciences Fellowships for Young International Scientists (2010Y2ZB04).

PY - 2013/10

Y1 - 2013/10

N2 - Here we demonstrate a calcifying ureolytic bacterium Bacillus sp. CS8 for the bioremediation of chromate (Cr(VI)) from chromium slag based on microbially induced calcite precipitation (MICP). A consolidated structure like bricks was prepared from chromium slags using bacterial cells, and five stage Cr(VI) sequential extraction was carried out to know their distribution pattern. Cr(VI) mobility was found to significantly be decreased in the exchangeable fraction of Cr slag and subsequently, the Cr(VI) concentration was markedly increased in carbonated fraction after bioremediation. It was found that such Cr slag bricks developed high compressive strength with low permeability. Further, leaching behavior of Cr(VI) in the Cr slag was studied by column tests and remarkable decrease in Cr(VI) concentration was noticed after bioremediation. Cr slags from columns were characterized by SEM-EDS confirming MICP process in bioremediation. The incorporation of Cr(VI) into the calcite surface forms a strong complex that leads to obstruction in Cr(VI) release into the environment. As China is facing chromium slag accidents at the regular time intervals, the technology discussed in the present study promises to provide effective and economical treatment of such sites across the country, however, it can be used globally.

AB - Here we demonstrate a calcifying ureolytic bacterium Bacillus sp. CS8 for the bioremediation of chromate (Cr(VI)) from chromium slag based on microbially induced calcite precipitation (MICP). A consolidated structure like bricks was prepared from chromium slags using bacterial cells, and five stage Cr(VI) sequential extraction was carried out to know their distribution pattern. Cr(VI) mobility was found to significantly be decreased in the exchangeable fraction of Cr slag and subsequently, the Cr(VI) concentration was markedly increased in carbonated fraction after bioremediation. It was found that such Cr slag bricks developed high compressive strength with low permeability. Further, leaching behavior of Cr(VI) in the Cr slag was studied by column tests and remarkable decrease in Cr(VI) concentration was noticed after bioremediation. Cr slags from columns were characterized by SEM-EDS confirming MICP process in bioremediation. The incorporation of Cr(VI) into the calcite surface forms a strong complex that leads to obstruction in Cr(VI) release into the environment. As China is facing chromium slag accidents at the regular time intervals, the technology discussed in the present study promises to provide effective and economical treatment of such sites across the country, however, it can be used globally.

KW - Biocement

KW - Bioremediation

KW - Calcite

KW - Chromium slag

KW - Urease

UR - http://www.scopus.com/inward/record.url?scp=84885835816&partnerID=8YFLogxK

U2 - 10.1016/j.chemosphere.2013.08.008

DO - 10.1016/j.chemosphere.2013.08.008

M3 - 文章

C2 - 24001665

AN - SCOPUS:84885835816

SN - 0045-6535

VL - 93

SP - 1352

EP - 1358

JO - Chemosphere

JF - Chemosphere

IS - 7

ER -