One framework type of high-silica zeolite only can effectively remove a limited range of organic micropollutants (OMPs) from water. In order to extend the OMP removal range, different types of high-silica zeolites need to be combined in the adsorption process. In this study, Mordernite (MOR) and ZSM-5 (MFI) high-silica zeolite powders were mixed in different mass ratios. The removal performances of eight OMPs by zeolite mixtures, as well as single MOR and MFI zeolites, were evaluated through batch adsorption experiments to investigate their adsorption behaviors and mechanisms. When there was only one solute in water, the adsorption isotherms of OMPs by zeolite mixtures were well predicted by combining the experimental adsorption isotherms of single zeolites based on the mass ratios of single zeolites. In multi-solute water, adsorption isotherms by zeolite mixtures were calculated with less accuracy when solely combining experimental isotherms of single zeolites, especially in the case of having a lower portion of more-effective zeolite in the mixture. This could be attributed to the competition for more-effective zeolite between different OMPs.@en

Electrolysis and permanganate (PM) oxidation are two commonly used technologies for water treatment. However, they are often handicapped by their slow reaction rates. To improve the removal efficiency of refractory contaminants, we combined electrolysis with PM using an activated carbon fiber (ACF) as cathode (E-ACF-PM) for the first time to treat diclofenac (DCF) in aqueous solution. Up to 90% DCF was removed in 5 min by E-ACF-PM process. In comparison, only 3.95 and 27.35% of DCF was removed by individual electrolysis and PM oxidation at the same time, respectively. Acidic condition was more conducive to DCF removal. Surprisingly, soluble Mn(III) ( aq) formed on the surface of ACF was demonstrated as the principal oxidizing agent in E-ACF-PM process. Further studies showed that all three components (electrolysis + ACF + PM) were necessary to facilitate the heterogeneous generation of reactive Mn(III) ( aq). Moreover, SEM images and XPS spectra of ACF before and after treatment revealed that the morphologies and elemental compositions of reacted ACF were nearly unchanged during the E-ACF-PM process. ACF can be remained active and utilized to the rapid degradation of DCF in E-ACF-PM process even after reused for 20 times. Therefore, the E-ACF-PM process may provide a novel and effective alternative on the generation of reactive Mn(III) ( aq) in situ for water treatment by green electrochemical reactions.@en

Electrolysis and permanganate (PM) oxidation are two commonly used technologies for water treatment. However, they are often handicapped by their slow reaction rates. To improve the removal efficiency of refractory contaminants, we combined electrolysis with PM using an activated carbon fiber (ACF) as cathode (E-ACF-PM) for the first time to treat diclofenac (DCF) in aqueous solution. Up to 90% DCF was removed in 5 min by E-ACF-PM process. In comparison, only 3.95 and 27.35% of DCF was removed by individual electrolysis and PM oxidation at the same time, respectively. Acidic condition was more conducive to DCF removal. Surprisingly, soluble Mn(III) ( aq) formed on the surface of ACF was demonstrated as the principal oxidizing agent in E-ACF-PM process. Further studies showed that all three components (electrolysis + ACF + PM) were necessary to facilitate the heterogeneous generation of reactive Mn(III) ( aq). Moreover, SEM images and XPS spectra of ACF before and after treatment revealed that the morphologies and elemental compositions of reacted ACF were nearly unchanged during the E-ACF-PM process. ACF can be remained active and utilized to the rapid degradation of DCF in E-ACF-PM process even after reused for 20 times. Therefore, the E-ACF-PM process may provide a novel and effective alternative on the generation of reactive Mn(III) ( aq) in situ for water treatment by green electrochemical reactions.@en