Bacterial mineralization of chromium-copper spinel with highly performance in electroplating effluent

Zhongxuan Xu; Yuxi Chen; Zhen Wu; Diandi Li; Xiaoqin Li; Xuezhen Feng; Hong Deng; Hong Chen; Bintian Zhang; Zhang Lin

doi:10.1016/j.watres.2023.120229

Bacterial mineralization of chromium-copper spinel with highly performance in electroplating effluent

Water Res. 2023 Aug 15:242:120229. doi: 10.1016/j.watres.2023.120229. Epub 2023 Jun 14.

Authors

Zhongxuan Xu¹, Yuxi Chen¹, Zhen Wu¹, Diandi Li¹, Xiaoqin Li¹, Xuezhen Feng², Hong Deng³, Hong Chen², Bintian Zhang², Zhang Lin⁴

Affiliations

¹ School of Environment and Energy, The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Resource Recycling, South China University of Technology, Guangzhou 510006, China.
² School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
³ School of Environment and Energy, The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Resource Recycling, South China University of Technology, Guangzhou 510006, China. Electronic address: dengh2016@scut.edu.cn.
⁴ School of Environment and Energy, The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Resource Recycling, South China University of Technology, Guangzhou 510006, China; School of Metallurgy and Environment, Central South University, Changsha 410083, China. Electronic address: zhang_lin@csu.edu.cn.

PMID: 37331227
DOI: 10.1016/j.watres.2023.120229

Abstract

Cr (VI) contamination has posed severe challenges to water quality, food safety, and land resources. Microbial reduction of Cr(VI) to Cr(III) has drawn considerable attention due to its low cost and environmental friendliness. However, recent reports have shown that Cr(VI) generates highly migratable organo-Cr(III) rather than stable inorganic chromium minerals during the biological reduction process. In this work, it was reported for the first time that spinel structure CuCr₂O₄ was formed by Bacillus cereus in Cr biomineralization process. Different from known biomineralization models (biologically controlled mineralization and biologically induced mineralization), the chromium-copper minerals here appeared as specialized minerals with extracellular distribution. In view of this, a possible mechanism of biologically secretory mineralization was proposed. In addition, Bacillus cereus demonstrated a high conversion ability in the treatment of electroplating wastewater. The Cr(VI) removal percentage reached 99.7%, which satisfied the Chinese emission standard of pollutants for electroplating (GB 21,900-2008), indicating its application potential. Altogether, our work elucidated a bacterial chromium spinel mineralization pathway and evaluated the potential of this system for application in actual wastewater, opening a new avenue in the field of chromium pollution treatment and control.

Keywords: Bacterial Cr(VI) mineralization; Bacterial mineralization mechanism; Chromium-copper spinel; Cr(VI) contamination treatment and control; Wastewater treatment.

MeSH terms

Chromium / chemistry
Copper
Electroplating
Wastewater*
Water Pollutants, Chemical* / chemistry

Substances

chromium hexavalent ion
Wastewater
Copper
spinell
Chromium
Water Pollutants, Chemical