The effect of MWCNT treatment by H2O2and/or UV on fulvic acids sorption.
The carbon nanotubes (CNT) present in the wastewater subjected to treatment will possess altered physico-chemical properties. The changed properties will result in the unknown behavior of CNT in the environment after disposal; and it is expected to differ from their pristine analogues. In the present paper the effect of sorption of dissolved organic matter with fulvic acids (FA) as representatives onto UV and/or H2O2treated CNT was tested. Both kinetics and mechanism of sorption was estimated. The chemical adsorption was a rate limiting step and a pseudo-second order kinetics described the sorption of FA onto UV and/or H2O2treated CNT. The treating increased affinity towards FA and treating by UV and H2O2simultaneously possessed greater impact on k2than UV and H2O2separately. The greatest effect on CNT sorption capacity revealed H2O2. The sorption mechanism was described by Temkin (CNT-H2O2) and Dubinin-Radushkevich model. The increase in CNT surface disorder caused by UV and/or H2O2treatment favored sorption of FA via π-π interactions (exfoliated surface and disordered CNT walls). FA sorption occurred between aromatic rings of FA and CNT and hydrogen bonds formed with the oxygen functional groups. The results indicate that UV and/or H2O2treatment affected the sorption capacity and affinity of CNT towards FA.
Department of Environmental Chemistry, Faculty of Chemistry, Maria Curie-Skłodowska University, Pl. M. Cure-Skłodowskiej 3, 20-031 Lublin, Poland. Electronic address: bczech@hektor.umcs.lublin.pl.
Bożena
B
Czech
D000327:Adsorption; D001578:Benzopyrans / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry / Q000528:radiation effects; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000528:radiation effects
D001578:Benzopyrans; D037742:Nanotubes, Carbon; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; C005023:fulvic acid
Advanced oxidation processes; CNT; Dissolved organic matter; Fulvic acids; Sorption