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In this paper, the degradation mechanism and eco-toxicity assessment of bisphenol S (BPS) was studied in the aqueous environment based on the heterogeneous activation of peroxymonosulfate (PMS) through spinel tricobalt tetraoxide (Co 3 O 4) catalyst using density functional theory (DFT) and computational toxicology methods. The result indicates that (100) and (311) surfaces have the higher proportion of bivalent cobalt, the increase of charge transfer, negative adsorption energy, and the lower surface energy. They can more effectively promote the decomposition of PMS to generate reactive oxide species. When generated oxidants react with BPS, HO•-addition reaction at the ortho -C atom-sites plays a dominant role in the system Co 3 O 4 /PMS. The presence of SO 4 •-, HO•, and O 2 promotes the formation of transformation intermediates and products. The formation pathways of important experimental intermediates hydroquinone, p -hydroxybenzenesulfonic acid, and 3, 4-dihydroxybenzenesulfonic acid are identified. And, some hydroxylation products that are not identified in the experiment are determined. The eco-toxicity evaluation shows that most of the decomposition products are completely harmless or significantly reduced compared to BPS. This study not only provides insights into the degradation mechanism of BPS in Co 3 O 4 /PMS system, but also is expected to be a guide for further experimental research and the design and optimization of the activated catalysts in sulfate radical-based advanced oxidation technologies. [Display omitted] • Co 3 O 4 (100) and (311) surfaces are more effectively promote the PMS decomposition. • The most reactive-site of BPS is the ortho -C atom. • OH.•-initiated plays a dominant role in the degradation process of BPS, not SO 4 •-. • Hydroquinone and p-hydroxybenzenesulfonic acid are important intermediates. • Compared with BPS, most decomposition products are harmless or reduced. [ABSTRACT FROM AUTHOR]

Terbutaline (TBL, an β-agonists pharmaceuticals) is one of the pharmaceuticals and personal care products (PPCPs), which has caused many environmental concerns due to its eco-toxicological effects in aquatic environment. In this research, density functional theory (DFT) and quantitative structure–activity relationships (QSARs) toxicity methods were performed to systematically elucidate the transformation mechanisms and ecological risk of TBL degraded by •OH and O 3. By analyzing the structure and electronic properties of TBL, the •OH-addition, H-abstraction, single electron transfer and 1, 3-cycloaddition ozonation degradation pathways were mainly investigated. The lowest energy barriers of •OH and O 3 initiated reactions in the degradation process were 7.33 and 18.49 kcal mol−1 respectively, which indicated that the •OH degradation process was more likely to occur than O 3 induced reactions from a thermodynamic perspective. The kinetic rate constants of O 3 and •OH at 298 K were calculated as 7.58 M−1 s−1 and 1.02 × 109 M−1 s−1, respectively. Furthermore, the subsequent intermediates could further transform into hydroxylation substitutes, glyoxylic acid and ketoaldehyde by-products. Based on toxicity assessments, parent reactant TBL can exhibit harmful acute and chronic toxicity to daphnid (identified by LC 50 33.2 mg L−1 and ChV 2.34 mg L−1). The toxicity of most of the degradation products was reduced to harmless level compared with the parent reactant TBL. This work provided a molecular level understanding for evaluating the contribution of O 3 and •OH to the removal of TBL from wastewater by theoretical calculations. [Display omitted] • The degradation mechanisms of terbutaline by.•OH and O 3 in aquatic environment were studied by theoretical calculation methods. • The main degradation mechanism was proposed as an.•OH-addition reaction on the C1 site of aromatic ring of terbutaline. • The calculated total rate constants of.•OH and O 3 -initiated reaction were 1.02 × 109 M−1 s−1 and 7.58 M−1 s−1 during the degradation of terbutaline at 298K. • The eco-toxicity of degradation by-products were changed compared by terbutaline. [ABSTRACT FROM AUTHOR]

Nowadays, the widespread existence and potential adverse effects of emerging micropollutants in waters have prompted the search for effective treatment methods. In this study, the feasibility of UV/O 3 /PMS (peroxymonosulfate, HSO 5 −) method for the elimination of Flutamide (FLU) was comprehensively investigated, with focus on transformation behaviors and risk assessment. The results showed that the UV/O 3 /PMS method has excellent oxidation capability to FLU with the elimination efficiency of 83.7% within 40 min. In addition, the radical (·OH and SO 4 −·) oxidation occupies greater advantages in the initiation reaction pathways of FLU compared to non-radical (O 3 and 1O 2) oxidation. With the participation of H 2 O 2 , H 2 O, O 2 , and ·OH, eleven transformation products (TPs) are generated through hydroxylation, demethylation, and decomposition reactions. According to the risk assessment results, the toxicity of most TPs gradually decreased, but the residual developmental toxicity could not be ignored. Further, the environmental persistence of FLU was evaluated with respect to natural water and advanced oxidation processes. These findings could help to advance the fundamental understanding of emerging micropollutants in the aquatic environments, and provide a basis for their practical application in water treatment. [Display omitted] • The transformation mechanisms involved in UV/O 3 /PMS system were elucidated. • ·OH and SO 4 −· are the major contributors to FLU degradation compared to O 3 and 1O 2. • FLU degradation was caused by hydroxylation, demethylation, and decomposition paths. • UV/O 3 /PMS is a promising treatment method for O 3 or UV-refractory micropollutants. [ABSTRACT FROM AUTHOR]

Reuse of agricultural and industrial wastes simultaneously to prepare hydrochars (HCs) for removal of NH 4 + and PO 4 3− in practical sewage without additional wastes produced is still a challenge. Herein, HCs were fabricated by combination of rape straw and industrial sewage sludge to remove NH 4 + and PO 4 3− from hoggery effluent. Synthesis conditions were firstly optimized and optimized HC (OPT-HC) was further applied to adsorb NH 4 + and PO 4 3−. Monolayer and Pseudo-first-order as well as Pseudo-second-orders were confirmed via adsorption kinetic and isothermal adsorption studies. Morphologies and surface areas of the OPT-HC did not show any transformations before and after adsorption of NH 4 + and PO 4 3−. The OPT-HC after adsorption of NH 4 + and PO 4 3− (OPT–HC–N/P) was further applied as fertilizer for planting Ping-pong Chrysanthemum. Results indicate that the OPT–HC–N/P can improve comprehensive qualities of the Ping-pong Chrysanthemum such as plant height, fresh, Vitamin C, Chlorophyll, soluble protein and sugar because the OPT–HC–N/P can provide extra N and P elements and also promote to release available K in soil. OPT–HC–N/P treated Ping-pong Chrysanthemum open flowers in advance. Thus, two kinds of wastes were re-utilized to remove N and P in real-life effluent. • Agricultural and industrial wastes were used to prepare hydrochars. • The hydrochars can be applied to remove N and P in hoggery effluent. • No wastes produced after removal of N and P. • Horticultural/agricultural applications were further realized. • Qualities of Ping-pong Chrysanthemum improved by HC after adsorption of N and P. [ABSTRACT FROM AUTHOR]

Hydrometallurgy is the main method to regenerate valuable metals from electroplating sludge and reduce its environmental hazards. As a key step to efficiently recover metals, it is important to choose an environmentally friendly and efficient leaching agent. In this work, four green ionic liquid (ILs) ([BMIm]HSO 4 , [HOOCMIm]HSO 4 , [BSO 3 HMIm]HSO 4 , and [BSO 3 ]Py.HSO 4) were used to leach copper from copper–rich electroplating sludge (C–ES). The tested ILs could effectively leach copper from C–ES, but functionalized ILs have better leaching efficiency, especially sulfonate ILs, which could remove 100% of Cu from C–ES under optimal conditions. Kinetics studies showed that the leaching process of controlled by chemical reaction and material diffusion, and the apparent activation energies were 39.21, 0.98, 14.47, and 41.93 kJ mol−1, respectively. Introducing functional groups (such as carboxyl and sulfonate group) which can complex with metals on cations can enhance the H+ release and complexation ability of ILs, improve the mass transfer efficiency between liquid–solid phase, and thus improve the copper leaching ability by ILs. These findings are of great significance for selecting functional ILs to efficiently regenerate copper and the resource utilization from C–ES. [Display omitted] • An efficient leaching method of copper from electroplating sludge is proposed. • The leaching behavior and the leaching mechanism of copper in ILs was analysed. • Functionalized ILs had better hydrogen release and metal complexation ability. • Sulfonate functionalized ILs is most conducive to copper recovery from C-ES. [ABSTRACT FROM AUTHOR]

The cost–effective removal and recovery of phosphate from wastewater is of great importance to controlling eutrophication and alleviating the phosphorus resource exhaustion crisis. Herein, chitosan (Cs) encapsulated bimetallic lanthanum (La) and iron (Fe) metal(hydro) oxides (La/Fe–Cs) composites were fabricated using a co–precipitated method for enhanced phosphate removal and recovery. The La/Fe–Cs composites had rough and raised spongy–like surfaces coated with La/Fe (hydr)oxide particles with a high specific surface area of 109.84 m2 g−1, providing more potential binding sites for phosphate capture. The La/Fe–Cs composites with a 1:2 La–to–Fe molar ratio exhibited a maximum adsorption capacity of 67.52 mg g−1 for phosphate at 308 K, calculated using the Langmuir model, which was 211% higher than that of monometallic Fe–Cs composites. Meanwhile, this composite also showed a high phosphate removal rate (63–95%) in an extensive applicable pH range (3.00–10.00) and rapid adsorption within 10 min (up to 94%). Moreover, the adsorption of phosphate by La/Fe–Cs composites was mildly disturbed against co–existing ions of NO 3 −, Cl−, and humic acid, while adsorption capacities were reduced by almost 13–45% with the existence of SO 4 2−, HCO 3 −, and CO 3 2−. The FTIR, XPS, and DFT results suggested that La–doped facilitated phosphate removal and the predominant mechanisms involved electrostatic interaction, surface precipitation, and inner–sphere complexation processes. Additionally, La/Fe–Cs composites also illustrated excellent efficiencies in simultaneous scavenging phosphate and ammonia from eutrophication and poultry wastewater. These results highlight bimetallic La/Fe–Cs composites are promising candidates for efficient elimination and recovery of phosphate from real wastewater, and subsequently could be used as slow–release fertilizers or soil amendments. [Display omitted] •Bimetallic La/Fe–Cs composites were synthesized for phosphate removal. • The derived bimetallic La/Fe–Cs composites showed excellent phosphate adsorption capacity of 67.52 mg g−1 • Mechanisms driving phosphates adsorbed onto the La/Fe–Cs composites were elucidated by FTIR, XPS, and DFT. • High efficiency in scavenging phosphate from eutrophication wastewater and poultry wastewater. • The phosphate–loden La/Fe–Cs composites can be used as slow–release fertilizers or soil amendments. [ABSTRACT FROM AUTHOR]

The cost–effective removal and recovery of phosphate from wastewater is of great importance to controlling eutrophication and alleviating the phosphorus resource exhaustion crisis. Herein, chitosan (Cs) encapsulated bimetallic lanthanum (La) and iron (Fe) metal(hydro) oxides (La/Fe–Cs) composites were fabricated using a co–precipitated method for enhanced phosphate removal and recovery. The La/Fe–Cs composites had rough and raised spongy–like surfaces coated with La/Fe (hydr)oxide particles with a high specific surface area of 109.84 m2 g−1, providing more potential binding sites for phosphate capture. The La/Fe–Cs composites with a 1:2 La–to–Fe molar ratio exhibited a maximum adsorption capacity of 67.52 mg g−1 for phosphate at 308 K, calculated using the Langmuir model, which was 211% higher than that of monometallic Fe–Cs composites. Meanwhile, this composite also showed a high phosphate removal rate (63–95%) in an extensive applicable pH range (3.00–10.00) and rapid adsorption within 10 min (up to 94%). Moreover, the adsorption of phosphate by La/Fe–Cs composites was mildly disturbed against co–existing ions of NO 3 −, Cl−, and humic acid, while adsorption capacities were reduced by almost 13–45% with the existence of SO 4 2−, HCO 3 −, and CO 3 2−. The FTIR, XPS, and DFT results suggested that La–doped facilitated phosphate removal and the predominant mechanisms involved electrostatic interaction, surface precipitation, and inner–sphere complexation processes. Additionally, La/Fe–Cs composites also illustrated excellent efficiencies in simultaneous scavenging phosphate and ammonia from eutrophication and poultry wastewater. These results highlight bimetallic La/Fe–Cs composites are promising candidates for efficient elimination and recovery of phosphate from real wastewater, and subsequently could be used as slow–release fertilizers or soil amendments. [Display omitted] •Bimetallic La/Fe–Cs composites were synthesized for phosphate removal. • The derived bimetallic La/Fe–Cs composites showed excellent phosphate adsorption capacity of 67.52 mg g−1 • Mechanisms driving phosphates adsorbed onto the La/Fe–Cs composites were elucidated by FTIR, XPS, and DFT. • High efficiency in scavenging phosphate from eutrophication wastewater and poultry wastewater. • The phosphate–loden La/Fe–Cs composites can be used as slow–release fertilizers or soil amendments. [ABSTRACT FROM AUTHOR]