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The occurrence of 12 pharmaceuticals and personal care products (PPCPs) in two wastewater treatment plants in Beijing was studied monthly over the course of one year. The removal of PPCPs by three biological treatment processes including conventional activated sludge (CAS), biological nutrient removal (BNR), and membrane bioreactor (MBR) was compared during different seasons. Seasonal variations of PPCPs in the wastewater influent were discrepant, while in the wastewater effluent, most PPCPs had lower concentrations in the summer than in the winter. For the easily biodegradable PPCPs, the performance of MBR was demonstrated to be more stable than CAS or BNR especially during winter months. Diclofenac, trimethoprim, metoprolol, and gemfibrozil could be moderately removed by MBR, while their removal by CAS and BNR was much lower or even negligible. Nevertheless, no removal was achieved regardless of the season or the treatment processes for the recalcitrant PPCPs. Studies on the contribution of each tank of the MBR process to the total removal of four biodegradable PPCPs indicated the oxic tank was the most important unit, whereas membrane filtration made a negligible contribution to their elimination.

The Bismuth oxyhalides, crystalline BiOX (X = Cl, Br, I) were prepared via a facile method, using NaBiO 3 25 and HX aqueous solutions as the raw materials for the first time. The systematic microstructure and opti-26 cal property characterizations of the BiOX photocatalysts demonstrated the reliability of this new and 27 facile preparation approach. The photocatalytic activity on the degradation of typical phenolic endocrine 28 disrupting chemicals over BiOX and P25 were evaluated under Xenon-light irradiation and the initial 29 photocatalytic mechanism was discussed based on the band edge potential analysis. 30 Ó 2009 Published by Elsevier B.V. 31 65 4f 5/2 , Bi 4f 7/2 , respectively. The peaks were centered at 165.1 and 66 159.8 eV in the BiOX samples corresponding to the binding energy 67 of Bi 4f 5/2 and Bi 4f 7/2 , demonstrating that the main chemical states 68 of Bismuth element in the samples were tri-valence [8]. The results 69 from the XPS and XRD demonstrate that there were unreduced 70 Bi 2 O 5 (V) phases in the samples. 71 The sheet-morphology of BiOCl, BiOBr and BiOI samples was ob-72 served on Field Emission Gun-Scanning Electronic Microscope 73 (FEG-SEM). Meanwhile, the Energy Dispersive X-ray analysis 74 (EDX) results indicated that Bi, O and X element from the crystals 75 were in stoichiometric amount. The Bright-Field Transmittance 76 Electronic Microscopy (BF-TEM) images of BiOX series crystals 77 were recorded by using a small objective aperture that selected 78 only the (0 0 0) central transmitted beam, showing that the parti-79 cle sizes of BiOX were around 690 nm, 650 nm and 120 nm, respec-80 tively. Such results were in accordance with the FEG-SEM results. 81 The particles were found to have single crystalline feature of the 82 BiOX samples, shown by electron diffraction patterns and addition-83 ally proved by high-resolution lattice imaging of individual

Pharmaceutical and personal care products (PPCPs) have been the focus of increasing concern in recent decades due to their ubiquity in the environment and potential risks. Out-of-date PPCPs are usually discharged into municipal solid wastes (MSWs), enter the leachates in MSW landfills and have serious adverse effects on the surrounding water environment. However, the occurrence and removal of PPCPs from landfill leachates have rarely been examined to date. This lack of knowledge makes landfill an underestimated source of PPCPs in the environment. In this review, we collected the relevant publications of PPCPs in landfill leachates, systematically summarized the occurrence of PPCPs in landfill leachates globally, evaluated the removal performances for various PPCPs by different types of on-site fullscale leachate treatment processes, and assessed the impacts of landfill leachates on PPCPs in the adjacent groundwater. In particular, influencing factors for PPCPs in landfill leachates, including the physicochemical properties of PPCPs, climate conditions, characteristics of landfill sites (i.e., landfill ages) as well as sociological factors (i.e., economic development) were extensively discussed to understand their occurrence patterns. Future perspectives were also proposed in light of the identified knowledge gaps. To the best of our knowledge, this is the first review regarding the occurrence and removal of PPCPs from landfill leachates worldwide.

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In this study, thermally activated persulfate (PS) to stimulate the oxidation of 1,1,1-trichloroethane (TCA) in groundwater remediation was investigated. The effects of various factors including temperature; initial TCA concentration; PS/ TCA molar ratio; solution pH; and common constituents in groundwater such as Cl À , HCO 3 À , SO 4 2À , and NO 3 À anions and humic acid (HA) were evaluated. The experimental results showed that TCA can be completely oxidized in 2 h at 50 °C with a PS/ TCA molar ratio of 100/1, indicating the effectiveness of thermally activated PS oxidation for TCA removal. TCA oxidation was fitted with a pseudo-first-order kinetic model, and the rate constant was found to increase with increasing temperature and PS/TCA molar ratio, but to decrease with increasing initial TCA concentration. In addition, acidic conditions were favorable to TCA removal and elevating, the initial solution pH value (from pH 3 to 11) decreased the TCA degradation rate. Anions Cl À and HCO 3 À had negative effects on TCA removal, whereas the effects of both SO 4 2À and NO 3 À were negligible. With 5À10 mg L À1 concentrations of HA in solution, an inhibitive effect was observed, indicating that dissolved organic matter consumed some of the oxidant. However, the anticipated effective thermally activated PS oxidation of TCA in groundwater from a real contaminated site was not achieved because of the complex solution matrix. On the other hand, the TCA degradation mechanism derived from GC/MS analytical results confirmed formic acid, dichloromethane, and trichloromethane as the primary intermediates, and therefore, two TCA decomposition pathways were proposed. In conclusion, thermally activated PS oxidation is a highly promising technique for TCA-contaminated groundwater remediation, but more complex constituents in in situ groundwater should be carefully considered for its practical application.

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