title: Removal of trace metals and improvement of dredged sediment dewaterability by bioleaching combined with Fenton-like reaction.
abstract: Bioleaching by Aspergillus niger strain SY1 combined with Fenton-like reaction was optimized to improve trace metal removal and dewaterability of dredged sediments. The major optimized parameters were the duration of bioleaching and H₂O₂ dose in Fenton-like process (5 days and 2g H₂O₂/L, respectively). Bioleaching resulted in the removal of ≈90% of Cd, ≈60% of Zn and Cu, ≈20% of Pb, and in decrease of sediment pH from 6.6 to 2.5 due to organic acids produced by A. niger. After addition of H₂O₂, Fenton-like reaction was initiated and further metal removal occurred. Overall efficiency of the combined process comprised: (i) reduction of Cd content in sediment by 99.5%, Cu and Zn by >70% and Pb by 39% as a result of metal release bound in all mobilizable fractions; (ii) decrease of sediment capillary suction time (CST) from 98.2s to 10.1s (by 89.8%) and specific resistance to filtration (SRF) from 37.4×10(12)m/kg to 6.2×10(12)m/kg (by 83.8%), due to reducing amount of extracellular polymeric substances (EPS) by 68.7% and bound water content by 79.1%. The combined process was found to be an efficient method to remove trace metals and improve dewaterability of contaminated dredged sediments.
authors: Key Laboratory of Pollution Ecology and Environment Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China; Center for Environmental Biotechnology, The University of Tennessee, Knoxville, TN 37996, USA; University of Chinese Academy of Sciences, Beijing 100039, PR China.
authors: Xiangfeng
authors: X
authors: Zeng
authors: Institute of Environmental Engineering of the Polish Academy of Sciences, Zabrze 41-819, Poland.
authors: Irena
authors: I
authors: Twardowska
authors: Key Laboratory of Pollution Ecology and Environment Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China. Electronic address: shuhewei@iae.ac.cn.
authors: Shuhe
authors: S
authors: Wei
authors: Key Lab of Regional Environment and Eco-Remediation (Ministry of Education), Shenyang University, 110073, PR China.
authors: Lina
authors: L
authors: Sun
authors: Center for Environmental Biotechnology, The University of Tennessee, Knoxville, TN 37996, USA.
authors: Jun
authors: J
authors: Wang
authors: Center for Environmental Biotechnology, The University of Tennessee, Knoxville, TN 37996, USA.
authors: Jianyu
authors: J
authors: Zhu
authors: Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan 430074, PR China.
authors: Jianchao
authors: J
authors: Cai
mesh_terms: D001234:Aspergillus niger / Q000378:metabolism; D001673:Biodegradation, Environmental; D002104:Cadmium / Q000737:chemistry; D003300:Copper / Q000737:chemistry; D005374:Filtration; D019015:Geologic Sediments / Q000032:analysis*; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007501:Iron; D008670:Metals / Q000032:analysis*; D012722:Sewage; D015032:Zinc / Q000737:chemistry
chemical_list: C045076:Fenton's reagent; D008670:Metals; D012722:Sewage; D002104:Cadmium; D003300:Copper; D006861:Hydrogen Peroxide; D007501:Iron; D015032:Zinc
keywords: Aspergillus niger; Bioleaching; Dewaterability; Fenton-like reaction; Sediments; Trace metal removal