title: Nanoporous manganese oxides as environmental protective materials-effect of Ca and Mg on metals sorption.
abstract: The selectivity of nanoporous manganese oxides for some alkali and transition metals over calcium and magnesium was studied. Two tunnel-structured oxides (OMS-1 and OMS-2) were synthesized by means of a hydrothermal route. Competitive uptake of metals and acid was studied using batch kinetic measurements at different metal ion concentrations. The experimental data were correlated with a dynamic model. The results show that the studied OMS materials selectively adsorb Cu, Ni and Cd in the presence of Ca and Mg. It was also found that the exchange rates were reasonably high due to the small particle dimensions. Both materials are stable in the studied conditions and their maximum Cu uptake capacity was 0.9-1.3 mmol/g. The results indicate that both materials have potential for environmental applications involving the uptake of harmful metal ions.
authors.affiliation: Lappeenranta University of Technology, Laboratory of Industrial Chemistry, FI-53851 Lappeenranta, Finland. Jouni.Pakarinen@lut.fi
authors.forename: Jouni
authors.initials: J
authors.lastname: Pakarinen
authors.forename: Risto
authors.initials: R
authors.lastname: Koivula
authors.forename: Markku
authors.initials: M
authors.lastname: Laatikainen
authors.forename: Katri
authors.initials: K
authors.lastname: Laatikainen
authors.forename: Erkki
authors.initials: E
authors.lastname: Paatero
authors.forename: Risto
authors.initials: R
authors.lastname: Harjula
mesh_terms: D000327:Adsorption; D002118:Calcium / Q000737:chemistry*; D003247:Conservation of Natural Resources; D008274:Magnesium / Q000737:chemistry*; D008670:Metals / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D036103:Nanotechnology; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D008670:Metals; D008274:Magnesium; D002118:Calcium