title: Influence of pH, competing ions, and salinity on the sorption of strontium and cobalt onto biogenic hydroxyapatite.
abstract: Anthropogenic radionuclides contaminate a range of environments as a result of nuclear activities, for example, leakage from waste storage tanks/ponds (e.g. Hanford, USA or Sellafield sites, UK) or as a result of large scale nuclear accidents (e.g. Chernobyl, Ukraine or Fukushima, Japan). One of the most widely applied remediation techniques for contaminated waters is the use of sorbent materials (e.g. zeolites and apatites). However, a key problem at nuclear contaminated sites is the remediation of radionuclides from complex chemical environments. In this study, biogenic hydroxyapatite (BHAP) produced by Serratia sp. bacteria was investigated for its potential to remediate surrogate radionuclides (Sr(2+) and Co(2+)) from environmentally relevant waters by varying pH, salinity and the type and concentration of cations present. The sorption capacity of the BHAP for both Sr(2+) and Co(2+) was higher than for a synthetically produced hydroxyapatite (HAP) in the solutions tested. BHAP also compared favorably against a natural zeolite (as used in industrial decontamination) for Sr(2+) and Co(2+) uptake from saline waters. Results confirm that hydroxyapatite minerals of high surface area and amorphous calcium phosphate content, typical for biogenic sources, are suitable restoration or reactive barrier materials for the remediation of complex contaminated environments or wastewaters.
authors.affiliation: Schools of Geography, Earth and Environmental Sciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, U.K.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Handley-Sidhu
authors.affiliation: Civil and Environmental Engineering, University of Strathclyde, Glasgow, G1 1XQ, U.K.
authors.forename: Thomas K
authors.initials: TK
authors.lastname: Mullan
authors.affiliation: Schools of Geography, Earth and Environmental Sciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, U.K.
authors.forename: Quentin
authors.initials: Q
authors.lastname: Grail
authors.affiliation: Schools of Geography, Earth and Environmental Sciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, U.K.
authors.forename: Malek
authors.initials: M
authors.lastname: Albadarneh
authors.affiliation: Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibraki, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Ohnuki
authors.affiliation: School of Biosciences, The University of Birmingham.
authors.forename: Lynne E
authors.initials: LE
authors.lastname: Macaskie
mesh_terms: D000327:Adsorption; D001673:Biodegradation, Environmental; D003035:Cobalt / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007477:Ions; D008855:Microscopy, Electron, Scanning; D054712:Salinity; D012705:Serratia / Q000378:metabolism; D013324:Strontium / Q000737:chemistry*; D013499:Surface Properties; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D007477:Ions; D014874:Water Pollutants, Chemical; D003035:Cobalt; D017886:Durapatite; D013324:Strontium