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Carbamazepine (CBZ) is a typical class of pharmaceuticals and personal care products (PPCPs), and is a serious threat to the environment and human health. Photocatalytic degradation is an efficient technology to remove CBZ. However, the present work focused mainly on the improvement of photocatalytic degradation performance. The information about the effects of inorganic ions on the photocatalytic degradation activity of environmental pollutants is still scarce. This study systematically investigated the effects of inorganic ions on the photocatalytic degradation of CBZ in view of the practical applications. The addition of inorganic anions showed a negative effect on photocatalytic degradation of CBZ with the order of inhibition effects of HCO3− > Cl− > NO3−. This was due to the quenching effects of hydroxyl radicals or holes, which decreased the photocatalytic degradation of CBZ. The presence of Al3+ could adsorb on the surface of a photocatalyst to shield the active site, resulting in the decreased CBZ degradation, while coexistence of Ca2+ significantly promoted the photocatalytic degradation of CBZ owing to the enhanced CBZ adsorption. Mg2+ showed concentration and time-dependent effects (suppression or promotion) on the photocatalytic degradation of CBZ.

Contaminant arsenic(V) has been regarded as one of the top-priority pollutants to remove from water. In this contribution, different mesoporous Y-Al binary oxides were prepared by the wet impregnation method via varying the molar ratio of Y/Al in the range of 0.029 to 0.116. The manufactured materials were employed as adsorbent to separate arsenic(V) from water. The adsorbent was characterized by N2 adsorption--desorption isotherm, point of zero charge (PZC) and Fourier transform infrared (FT-IR). Furthermore, the effect of experimental parameters on adsorption performance was evaluated by batch experiments, including the molar ratio of Y/Al, adsorbent dosages and contact time, initial concentration, initial pH and temperature. The results indicated that the adsorbent presented an optimal adsorption performance for As(V) uptake when the molar ratio of Y/Al was 0.058. The obtained experimental data were best fitted by Langmuir isotherm and the maximum adsorption capacity was 60.93 mg/g at pH 6.6 ±0.1. Additionally, according to the results of adsorption kinetics, it was pronounced that adsorption process was complied with pseudo-second-order model. The adsorption thermodynamic suggested that the adsorption of As(V) is endothermic and spontaneous natural. Moreover, based on the results of FT-IR, PZC and initial pH, it is demonstrated that ion-exchange and electrostatic interaction were the dominating adsorption mechanism. [ABSTRACT FROM AUTHOR]

Ag speciation in a chloride medium was dependent upon the Cl/Ag ratio after releasing into surface water. In this study, the photoreaction of in situ formed Ag-Cl species and their effects on aniline photochlorination were systematically investigated. Our results suggested that formation of chloroaniline was strongly relevant to the Cl/Ag ratio and could be interpreted using the thermodynamically expected speciation of Ag in the presence of Cl-. AgCI was the main species responsible for the photochlorination of aniline. Both photoinduced hole and •OH drove the oxidation of Cl- to radical •Cl, which promoted the chlorination of aniline. Ag0 formation was observed from the surface plasmon resonance absorption during AgCI photoreaction. This study revealed that Ag+ released into Cl--containing water may result in the formation of chlorinated intermediates of organic compounds under solar light irradiation. [ABSTRACT FROM AUTHOR]