Bing Bai , Jing Chen , Bin Zhang , Liang Chen , Yongchen Zong
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引用次数: 0
Abstract
The remediation of heavy metal Pb2+-contaminated soil by enzyme (urease)-induced calcium carbonate precipitation (EICP) combined with biochar was studied. The solidification efficiency of Pb2+ reached 98.41 % when the mass ratio of CaCl2/urea was 1:1 using EICP technology to remedy Pb2+-contaminated water. However, the formed precipitate was accompanied by unstable vaterite, and Pb2+ had the risk of secondary leaching. When the biochar of 5 wt% was added to the Pb2+-contaminated soil, the soil structure tended to be dense and the toxic leaching concentration of Pb2+ was less than 5 mg/L, which met the national standard of China. The addition of biochar increased the pH of the contaminated soil and changed the free Pb2+ into insoluble Pb(OH)2. The biochar provided more nucleation sites for urease, and part of Pb2+ were adsorbed on its surface or diffused into the pores of biochar, which effectively solidified Pb2+ in the soil.
期刊介绍:
The Biochemical Engineering Journal aims to promote progress in the crucial chemical engineering aspects of the development of biological processes associated with everything from raw materials preparation to product recovery relevant to industries as diverse as medical/healthcare, industrial biotechnology, and environmental biotechnology.
The Journal welcomes full length original research papers, short communications, and review papers* in the following research fields:
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Bioresources and Biorefinery Engineering including biomass conversion, biofuels, bioenergy, and optimization
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Metabolic Engineering, Systems and Synthetic Biology including OMICS, bioinformatics, in silico biology, and metabolic flux analysis
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