Publications (5)4.56 Total impact
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Article: Lithium Ion Batteries
01/2010; -
Article: Adsorption of natural organic matter from waters by iron coated pumice.
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ABSTRACT: Natural pumice particles were used as granular support media and coated with iron oxides to investigate their adsorptive natural organic matter (NOM) removal from waters. The impacts of natural pumice source, particle size fraction, pumice dose, pumice surface chemistry and specific surface area, and NOM source on the ultimate extent and rate of NOM removal were studied. All adsorption isotherm experiments were conducted employing the variable-dose completely mixed batch reactor bottle-point method. Iron oxide coating overwhelmed the surface electrical properties of the underlying pumice particles. Surface areas as high as 20.6m(2)g(-1) were achieved after iron coating of pumice samples, which are above than those of iron coated sand samples reported in the literature. For all particle size fractions, iron coating of natural pumices significantly increased their NOM uptakes both on an adsorbent mass- and surface area-basis. The smallest size fractions (<63 microm) of coated pumices generally exhibited the highest NOM uptakes. A strong linear correlation between the iron contents of coated pumices and their Freundlich affinity parameters (K(F)) indicated that the enhanced NOM uptake is due to iron oxides bound on pumice surfaces. Iron oxide coated pumice surfaces preferentially removed high UV-absorbing fractions of NOM, with UV absorbance reductions up to 90%. Control experiments indicated that iron oxide species bound on pumice surfaces are stable, and potential iron release to the solution is not a concern at pH values of typical natural waters. Based on high NOM adsorption capacities, iron oxide coated pumice may be a promising novel adsorbent in removing NOM from waters. Furthermore, due to preferential removal of high UV-absorbing NOM fractions, iron oxide coated pumice may also be effective in controlling the formation of disinfection by-products in drinking water treatment.Chemosphere 01/2007; 66(1):130-8. · 3.21 Impact Factor -
Dataset: Kitis M., Akcil A., Karakaya E., Yigit, N.O., Destruction of cyanide by hydrogen peroxide (H2O2) in tailing slurry from low bearing sulphidic gold ores, Minerals Engineering, Vol.18, No.3, pp.353-362, 2005.
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ABSTRACT: The main objective of this work was to determine the effectiveness and kinetics of hydrogen peroxide in destroying cyanide in the tailings slurry from a gold mine with low sulphide and heavy metal content. The impacts of catalyst (Cu) and hydrogen peroxide concentrations, temperature and pH on the extent and rate of weak acid dissociable (WAD) cyanide destruction were investigated. Experiments were conducted using the variable-dose completely mixed batch reactor bottle-point method. Both the rate and extent of CNWAD destruction generally increased with increasing peroxide doses for either absence or presence of Cu catalyst. Catalyst addition was very effective in terms of not only enhancing the cyanide destruction rate but also significantly reducing the required peroxide dosages to achieve CNWAD concentrations of about 1 mg/l, independent of the temperatures tested (10, 20 and 30 �C). The initial cyanide destruction rates increased between 1.2 and 3 folds with the addition of 30 mg/l of Cu. Kinetic experiments showed that in most cases little CNWAD destruction occurred after a reaction time of 2–4 h. The impact of slurry pH on cyanide destruction varied depending upon the dosages of Cu catalyst. Relatively lower peroxide dose/CNWAD ratios required to achieve less than 1 mg/l of CNWAD may be due to lower heavy metals and sulphide content of the ore, resulting in lower peroxide requirement for metal bound cyanides. During cyanide destruction, nitrate was initially formed as a by-product and then possibly converted to other some volatile nitrogen-containing species, as supported by the mass balance calculations. -
Article: Destruction of cyanide by hydrogen peroxide in tailings slurries from low bearing sulphidic gold ores
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ABSTRACT: The main objective of this work was to determine the effectiveness and kinetics of hydrogen peroxide in destroying cyanide in the tailings slurry from a gold mine with low sulphide and heavy metal content. The impacts of catalyst (Cu) and hydrogen peroxide concentrations, temperature and pH on the extent and rate of weak acid dissociable (WAD) cyanide destruction were investigated. Experiments were conducted using the variable-dose completely mixed batch reactor bottle-point method. Both the rate and extent of CNWAD destruction generally increased with increasing peroxide doses for either absence or presence of Cu catalyst. Catalyst addition was very effective in terms of not only enhancing the cyanide destruction rate but also significantly reducing the required peroxide dosages to achieve CNWAD concentrations of about 1 mg/l, independent of the temperatures tested (10, 20 and 30 °C). The initial cyanide destruction rates increased between 1.2 and 3 folds with the addition of 30 mg/l of Cu. Kinetic experiments showed that in most cases little CNWAD destruction occurred after a reaction time of 2–4 h. The impact of slurry pH on cyanide destruction varied depending upon the dosages of Cu catalyst. Relatively lower peroxide dose/CNWAD ratios required to achieve less than 1 mg/l of CNWAD may be due to lower heavy metals and sulphide content of the ore, resulting in lower peroxide requirement for metal bound cyanides. During cyanide destruction, nitrate was initially formed as a by-product and then possibly converted to other some volatile nitrogen-containing species, as supported by the mass balance calculations.Minerals Engineering 18(3):353-362. · 1.35 Impact Factor -
Article: Adsorption of natural organic matter from waters by iron coated pumice
[show abstract] [hide abstract]
ABSTRACT: Natural pumice particles were used as granular support media and coated with iron oxides to investigate their adsorptive natural organic matter (NOM) removal from waters. The impacts of natural pumice source, particle size fraction, pumice dose, pumice surface chemistry and specific surface area, and NOM source on the ultimate extent and rate of NOM removal were studied. All adsorption isotherm experiments were conducted employing the variable-dose completely mixed batch reactor bottle-point method. Iron oxide coating overwhelmed the surface electrical properties of the underlying pumice particles. Surface areas as high as 20.6 m2 g−1 were achieved after iron coating of pumice samples, which are above than those of iron coated sand samples reported in the literature. For all particle size fractions, iron coating of natural pumices significantly increased their NOM uptakes both on an adsorbent mass- and surface area-basis. The smallest size fractions (<63 μm) of coated pumices generally exhibited the highest NOM uptakes. A strong linear correlation between the iron contents of coated pumices and their Freundlich affinity parameters (KF) indicated that the enhanced NOM uptake is due to iron oxides bound on pumice surfaces. Iron oxide coated pumice surfaces preferentially removed high UV-absorbing fractions of NOM, with UV absorbance reductions up to 90%. Control experiments indicated that iron oxide species bound on pumice surfaces are stable, and potential iron release to the solution is not a concern at pH values of typical natural waters. Based on high NOM adsorption capacities, iron oxide coated pumice may be a promising novel adsorbent in removing NOM from waters. Furthermore, due to preferential removal of high UV-absorbing NOM fractions, iron oxide coated pumice may also be effective in controlling the formation of disinfection by-products in drinking water treatment.Chemosphere.
