Biologically-induced precipitation of sphalerite–wurtzite nanoparticles by sulfate-reducing bacteria: Implications for acid mine drainage treatment

• Published in: The Science of the total environment Vol. 423; pp. 176 - 184
• Main Authors: Castillo, Julio, Pérez-López, Rafael, Caraballo, Manuel A., Nieto, José M., Martins, Mónica, Costa, M. Clara, Olías, Manuel, Cerón, Juan C., Tucoulou, Rémi
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.04.2012; Elsevier
• Subjects: Acid mine drainage; Applied sciences; Bacteria, Anaerobic - metabolism; Biodegradation, Environmental; Biological and medical sciences; Biological treatment of waters; Biotechnology; Chemical Precipitation; detection limit; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environment and pollution; Environmental Pollutants - chemistry; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Industrial applications and implications. Economical aspects; Industrial Waste; Industrial wastewaters; inoculum; landscapes; limestone; microscopy; Mining; nanoparticles; Nanoparticles - chemistry; Natural water pollution; Oxidation-Reduction; Particle Size; Pollution; Pollution, environment geology; Rainwaters, run off water and others; sediments; soil water; streams; sulfate-reducing bacteria; Sulfate-reducing bacteria (SRB); sulfides; Sulfides - chemistry; Treatment; Waste Management - methods; wastewater treatment; Wastewaters; Water treatment and pollution; zinc; Zinc - chemistry; Zinc Compounds - chemistry; zinc sulfate; Zinc tolerance; ZnS nanocrystals; Europe; Spain; Sulfate-reducing bacteria (SRB); ZnS nanocrystals; Treatment; Acid mine drainage; Zinc tolerance; Sulfate-reducing bacteria; Chemical precipitation; Nanoparticle; Heavy metal; Biological purification; Zinc sulfide; Trace element; Decontamination; Industrial waste water; Water pollution; Bioremediation; Waste water purification; Nanostructured materials
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2012.02.013

Several experiments were conducted to evaluate zinc-tolerance of sulfate-reducing bacteria (SRB) obtained from three environmental samples, two inocula from sulfide-mining districts and another inoculum from a wastewater treatment plant. The populations of SRB resisted zinc concentrations of 260mg/L for 42days in a sulfate-rich medium. During the experiments, sulfate was reduced to sulfide and concentrations in solution decreased. Zinc concentrations also decreased from 260mg/L to values below detection limit. Both decreases were consistent with the precipitation of newly-formed sphalerite and wurtzite, two polymorphs of ZnS, forming <2.5-μm-diameter spherical aggregates identified by microscopy and synchrotron-μ-XRD. Sulfate and zinc are present in high concentrations in acid mine drainage (AMD) even after passive treatments based on limestone dissolution. The implementation of a SRB-based zinc removal step in these systems could completely reduce the mobility of all metals, which would improve the quality of stream sediments, water and soils in AMD-affected landscapes. ► Experiments were conducted to assess Zn tolerance of sulfate-reducing bacteria (SRB). ► SRB were subjected to [Zn]=260mg/L for 42days in a sulfate-rich growth solution. ► Zn concentration was depleted by precipitation of spherical ZnS particles. ► ZnS corresponds to sphalerite and wurtzite according to synchrotron-based μ-XRD. ► This paper confirms the potential role of SRB in remediation of acid mine drainage.