6533b7d7fe1ef96bd1267bb0
RESEARCH PRODUCT
The removal of sulphate from mine water by precipitation as ettringite and the utilisation of the precipitate as a sorbent for arsenate removal.
Ulla LassiEmma-tuulia TolonenEmma-tuulia TolonenJaakko RämöTao Husubject
LangmuirEttringiteEnvironmental EngineeringSorbentInorganic chemistrychemistry.chemical_element02 engineering and technology010501 environmental sciencesManagement Monitoring Policy and Law01 natural sciencesMiningWater Purificationchemistry.chemical_compoundX-Ray DiffractionChemical PrecipitationFreundlich equationWaste Management and DisposalArsenic0105 earth and related environmental sciencesMineralsPrecipitation (chemistry)SulfatesArsenateSpectrometry X-Ray EmissionSorptionGeneral MedicineHydrogen-Ion Concentration021001 nanoscience & nanotechnologychemistryArsenatesAdsorption0210 nano-technologyWater Pollutants ChemicalElectron Probe Microanalysisdescription
Abstract The aim of this research was to investigate sulphate removal from mine water by precipitation as ettringite (Ca6Al2(SO4)3(OH)12·26H2O) and the utilisation of the precipitate as a sorbent for arsenate removal. The mine water sulphate concentration was reduced by 85–90% from the initial 1400 mg/L during ettringite precipitation depending on the treatment method. The precipitation conditions were also simulated with MINEQL + software, and the computational results were compared with the experimental results. The precipitated solids were characterised with X-ray diffraction and a scanning electron microscope. The precipitated solids were tested as sorbents for arsenate removal from the model solution. The arsenic(V) model solution concentration reduced 86–96% from the initial 1.5 mg/L with a 1 g/L sorbent dosage. The effect of initial arsenate concentration on the sorption of arsenate on the precipitate was studied and Langmuir, Freundlich, and Langmuir-Freundlich sorption isotherm models were fitted to the experimental data. The maximum arsenate sorption capacity (qm = 11.2 ± 4.7 mg/g) of the precipitate was obtained from the Langmuir-Freundlich isotherm. The results indicate that the precipitate produced during sulphate removal from mine water by precipitation as ettringite could be further used as a sorbent for arsenate removal.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2016-10-01 | Journal of environmental management |