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To better facilitate the resource utilization of secondary aluminum ash and reduce the consumption of Portland cement, this study investigates the pozzolanic activity grinding fine powder of secondary aluminum ash sintered and ground fine powder (MP) in a Portland cement matrix with different fineness and content. The mechanism of volcanic ash activity was explored using microscopic testing techniques such as XRD, FTIR, TG, SEM, and MIP. The outcomes revealed that as the MP content increased, the fluidity of the cement-based matrix exhibited a declining trend. The addition of MP has a diluting effect on Portland cement, resulting in a decreasing trend of strength activity index with the increase of MP content. Furthermore, under identical content conditions, much finer MP showed a reduction in its pozzolanic activity within the Portland cement-based matrix. Hydration processes and microscopic tests indicated that the addition of the coarser MP particle resulted in higher pozzolanic activity, which is attributed to the faster hydration rate, lower porosity, and higher microstructural compactness. Simultaneously, with an increase in MP content, the porosity and detrimental pore content of the cement-based matrix notably increased, and the content of hydration products reduced. [Display omitted] • The pozzolanic activity of MP in Portland cement matrix was characterized. • The influence of MP on the hydration kinetics of Portland cement was studied. • The pozzolanic activity mechanism of MP in Portland cement matrix was analyzed. [ABSTRACT FROM AUTHOR]

Manganese is a transition metal derived primarily from parent materials in soil. Weathered manganese, predominantly present as manganese oxides, is widely applied in ecological restoration owing to its large specific surface area and high reduction potential. Recently, manganese oxide (MnO x) and its modified materials have been increasingly reported for environmental pollution remediation due to their low toxicity, eco-friendliness and abundance. This review summarizes the synthesis, preparation, application and prospects of MnO x and its modified manganese-based materials, highlighting their effects on contaminated soil, water and air. MnO x and its derivatives are believed to find broader applications and marketability in environmental protection in the future. [Display omitted] • Reviews properties, mechanisms and applications of MnOx materials for environmental remediation. • Explores factors influencing MnOx catalytic and absorption efficiency. • Analyzes mechanistic pathways in MnOx catalysis and absorption. • Highlights the shortcomings of current research and prospects for the engineering application. [ABSTRACT FROM AUTHOR]

This paper explored the utilization of pottery sand (PS) sintered from heavy metal sludge (HMS) as fine aggregate in the high-strength cementitious matrix (HSCM), which can reduce the cost and facilitate the reutilization of HMS. To establish function expression for various parameters, D-Optimal Mixture Design (DOMD) method was adopted. Considering the comprehensive effects of multiple influencing factors, the optical mix proportion of HSCM with PS was ultimately proposed. Then, experimental verification was conducted on the proposed optimized mix ratio, indicating the accuracy of DOMD in calculating the mix ratio of the high-strength cementitious matrix with PS. Specifically, the optimal mix proportion exhibits superior performances in improving density, fluidity, mechanical properties, cost-effectiveness, and reducing carbon emissions. The appropriate inclusion of PS primarily serves to enhance the mechanical properties of the matrix and lower costs. The effects of PS on the porous structures and the characteristics of the interfacial transition zone (ITZ) between paste and fine aggregates were evaluated by scanning electron microscope (SEM), combining mercury intrusion porosimetry (MIP) and X-ray computed tomography (X-CT). It is found that the ITZ structure between paste and PS is much denser compared to that between paste and river sand. The appropriate content of PS is beneficial in reducing the mesoscopic porosity of HSCM. [Display omitted] • Design eco-friendly high-strength cementitious matrix with pottery sand from high-temperature sintered heavy metal sludge. • Optimize mixture proportion by comprehensively considering compactness, fluidity, mechanical properties, cost, and ecology. • Analyze the effects of pottery sand on the microstructure of high-strength cementitious matrix with MIP and X-CT. [ABSTRACT FROM AUTHOR]

• We identified a new nonsense mutation (c.637C > T p. Gln213Ter) of SERPINC1 gene. • SERPINC1 mutation-caused AT deficiency is the risk factor of CVST. • Is challenging to choose anticoagulants for AT deficiency. • New anticoagulants may exert a good anticoagulant effect. [ABSTRACT FROM AUTHOR]

Organophosphate esters (OPEs) are widely distributed in surface water systems, but limited information was available on the spatial occurrence and ecological risks of OPEs in the Bohai Sea. In this study, 89 water samples in the Bohai Sea and the five surrounding rivers were investigated for the determination of 15 OPEs. The concentration of ∑ 15 OPEs ranged from 373.20 to 2931.27 ng·L−1 in the river water and 137.81 to 2641.30 ng·L−1 in the seawater, with high levels of OPEs in Liaodong Bay. Tris(2-chloroethyl) phosphate (TCEP, 10– 92 %) and triethyl phosphate (TEP, 5– 64 %) were dominant for OPEs. The correlation analysis, principal component analysis and hierarchical cluster analysis suggested the conjunction of municipal wastewater via river input and maritime shipping was the main source of OPEs in the Bohai Sea. The ecological risk assessment indicated that the individual OPEs arise low ecological risks in the Bohai Sea, while medium ecological risks of ∑ 15 OPEs are in minority river samples. • OPEs were widely detected in the Bohai Sea and main input rivers. • TCEP and TEP were the most abundant OPEs. • River input and hydrodynamics condition influenced the spatial distributions of OPEs. • OPEs presented potential higher-level risks in estuaries than in seawater. [ABSTRACT FROM AUTHOR]

Polyphenols are organic substances commonly involved in a wide variety of industrial processes. They are prone to polymerize with other organic chemicals during production and subsequent wastewater treatment section, which yields various persistent and recalcitrant organic chemicals. To better understand the behavior of polyphenolic polymers in wastewater treatment processes and the effect on the biodegradability of wastewater, we explored the conversion of polyphenolic polymers during aerobic biochemical treatment and their relationship with extracellular polymeric substances (EPS). The COD Cr (chemical oxygen consumption measured using potassium dichromate) removal efficiency of the polyphenolic polymers with high concentration was only 29.66% with COD Cr of 437.5 mg/L, which was far from the wastewater discharge standard (60–100 mg/L, first class standard of GB 8978–1996). In the activated sludge system with stabilized organic matter as the substrate, the effluent had the highest degree of humification with the maximum SUVA value of 6.87 L/(mg∙m). The polyphenolic polymers caused a component variation in EPS, further affecting wastewater's humification degree and degradability. In particular, the content of humic acid-like substances in loose bound EPS (LB-EPS) was up to 4 times more than control, indicating higher aromatization and humification degree and of the waste. On the contrary, the content of polysaccharides in LB-EPS decreased by about 46.2–87.7% in treatments with different concentration of polyphenolic polymer. The high-concentration polyphenol polymers somehow stimulated the microbial production like proteins and humic-like substances. The direct conversion of polyphenol polymers also contributed to the increased humification of wastewater. • The accumulation of organic polymers was observed in the aerobic biochemical treatment. • Low-concentration polyphenol polymers can be degraded by microorganisms. • High-concentration polyphenol polymers increased the humification degree of wastewater during treatment. • The humic-like substances of microbial metabolites induced by polyphenolic polymers increased significantly. [ABSTRACT FROM AUTHOR]

Sustainable recycling of valuable metals from spent lithium-ion batteries (LIBs) may be necessary to alleviate the depletion of strategic metal resources and potential risk of environmental pollution. Herein a hydrometallurgical process was proposed to explore the possibility for the recovery of valuable metals from the cathode materials (LiCoO 2 ) of spent LIBs using phosphoric acid as both leaching and precipitating agent under mild leaching conditions. According to the leaching results, over 99% Co can be separated and recovered as Co 3 (PO 4 ) 2 in a short-cut process involved merely with leaching and filtrating, under the optimized leaching conditions of 40 °C (T), 60 min (t), 4 vol.% H 2 O 2 , 20 mL g −1 (L/S) and 0.7 mol/L H 3 PO 4 . Then leaching kinetics was investigated based on the logarithmic rate kinetics model and the obtained results indicate that the leaching of Co and Li fits well with this model and the activation energies (Ea) for Co and Li are 7.3 and 10.2 kJ/mol, respectively. Finally, it can be discovered from characterization results that the obtained product is 97.1% pure cobalt phosphate (Co 3 (PO4) 2 ). [ABSTRACT FROM AUTHOR]

Bioleaching has been demonstrated as a feasible and effective technology for removing Cr(III) from tannery sludge, but the recovery of bioleachate derived from tannery sludge by bioleaching is rarely reported. The purpose of this study was therefore to figure out the components of bioleachate and develop a chromium-iron tanning agent using the bioleachate and reuse it in tanning process. Component analysis indicated that the bioleachate contained high concentrations of Cr and Fe, as well as small quantities of other elements. The dissolved organic matter in the bioleachate was detected to be less than 1000 mg/L, which was mainly composed of polysaccharide, aliphatic or aromatic carboxylic acid compounds. A chromium-iron tanning agent was then prepared using the bioleachate, iron and chromium salts in a suitable ligand environment, and reused for tanning. In the tanning experiments, the pickled pigskins were tanned with this prepared tanning agent and the results indicated that chromium-iron tanned crust leather presented comparable physical and mechanical properties as well as air permeability when compared with conventional chromium tanned crust leather, but the thermal shrinkage temperature was about 4 °C lower than that of the chromium tanned crust leather. Therefore, this study provides not only a reuse route for tannery sludge bioleachate but also a clean tanning agent for leather processing. [ABSTRACT FROM AUTHOR]

With the rapid development of tanning industry, a noticeable number of chromium-containing tannery sludge (Cr-ITS) has been produced, which poses an impending threat to ecosystem and human health, and needs special disposal ahead of landfilling. In this study, an alternative method for thermally stabilizing Cr-ITS via employing ZnO and TiO 2 as dopants was developed. Oxidation of Cr(III), competitive formation of Cr-spinel, immobilization of Cr, and leaching toxicity of sintered products were investigated during Cr-ITS thermal treatment at the temperature range of 800–1200 ℃. Cr in Cr-ITS could be immobilized effectively through transforming Cr into spinel structure, as demonstrated by XRD analysis. Thus, the toxic Cr-ITS would be remedied and detoxified. Co-doping of ZnO and TiO 2 not only noticeable inhibited oxidation of Cr(III), but also accelerated conversion of Cr(III) to spinel dominated by ZnCr 2 O 4. Increasing temperature was conducive to the formation of spinel. Most of Cr were incorporated into spinel phase when thermal treatment temperature was over 1000 ℃, where Cr(VI) leached was not detected, and leaching concentrations of Cr and Zn after prolonged leaching time of 25 d were 13.32 mg/L and 23.07 mg/L respectively, which all meet regulatory limits. When increasing temperature to 1100 ℃, their leaching risk was further reduced to 4.39 mg/L and 5.24 mg/L respectively, successfully achieving simultaneous stabilization of heavy metals. The overall results indicate that Cr-ITS immobilized with ZnO and TiO 2 is a promising and feasible strategy by incorporating Cr into spinel phases using sintering temperature reached in ceramic industry. • Real chromium-containing tannery sludge was thermally treated under air atmosphere. • No Cr(VI) was detected in samples sintered above 1000℃. • Co-doping of ZnO and TiO 2 can inhibit oxidation of Cr(III) and accelerate formation of spinel dominated by ZnCr 2 O 4. • Leaching risks of Cr and Zn satisfy the regulatory limits by a prolonged leaching experiment. • Tannery sludge can be effectively detoxified and stabilized via synergic action of metals. [ABSTRACT FROM AUTHOR]

Pyrethroids are increasingly receiving attention as aqueous micropollutants, but their presence has been reported only in a few small coastal areas. In this study, we investigated the distribution, sources, and risks of nine pyrethroids in large marine zones. The 40 seawater samples were collected from the South Yellow Sea (SYS) and East China Sea (ECS) in China, during the spring of 2020, using a high-volume, solid-phase extraction method. The total pyrethroid concentrations ranged from 0.72 to 1.82 ng L−1 in the SYS and from 0.02 to 11.0 ng L−1 in the ECS. We used cluster analysis to classify pollutant sources into five categories, and discussed the influence of sources on the transport and distribution of pyrethroids in each group. Ecological risk assessment indicated that pyrethroids pose a high risk to crustaceans and a negligible risk to others. These results are important for understanding the behavior of pyrethroids in marine environments. [Display omitted] • Efficient Hi-throat/Hi-volume SPE was used to concentrate pyrethroids from seawater. • Occurrence of nine pyrethroids was investigated at South Yellow and East China Seas. • Distribution and sources are influenced by both human activities and ocean currents. • Ecological risk assessment indicated that pyrethroids pose a high risk to crustaceans. [ABSTRACT FROM AUTHOR]

In the last years, large attention has been devoted to the electrochemical treatment of wastewater polluted by recalcitrant organics and containing chlorides. However, the utilization on an applicative scale of this route is limited by the fact that usually it is not possible to achieve high removals of organics without the generation of significant amounts of chlorinated by-products. Here, the role of several operative parameters on the performances of the process was systematically evaluated using phenol as a model organic pollutant. It was shown that the removal of phenol and TOC and the generation of many by-products including chlorophenols, chloroacetic acids, chlorate and perchlorate dramatically depend on the adopted operative conditions (i.e., nature of anode and cathode, current density and concentration of chlorides). The use of boron doped diamond (BDD) anode gave the highest removal of TOC but also the highest final concentrations of chlorate and perchlorate and the lowest concentrations of chloroacetic acids. Conversely, the use of Ti/IrO 2 -Ta 2 O 5 gave the lowest generation of chlorate and no perchlorate. The use of lower current densities allowed as well to reduce the concentrations of these compounds. It is worth to mention that lower amounts of chlorinated by-products were achieved using suitable cathodes. Carbon felt cathodes, as previously reported for the water disinfection, allowed to reduce the generation of chlorate. Moreover, it was shown, for the first time, that the use of silver cathodes minimized the concentrations of chloroacetic acids. In addition, it was found that the use of a system equipped with both silver and carbon felt cathodes and proper current densities allowed to increase remarkably the removals of TOC and the current efficiency and to achieve very low concentrations of chlorinated by-products. [ABSTRACT FROM AUTHOR]

Abstract: Three azo dyes (Methyl Orange, Direct Brown and Direct Green) were treated by catalytic wet air oxidation (CWAO) with the catalysts CuO/γ-Al2O3 prepared by consecutive impregnation. The relationship of decolorization extent, chemical oxygen demand (COD) removal extent and total organic carbon (TOC) in dye solution were investigated. The results indicated that the CuO/γ-Al2O3 catalyst had excellent catalytic activity in treating azo dyes. Almost 99% of color and 70% of TOC were removed in 2h. The high removal extent of color and TOC indicated that the CWAO obtained perfect decomposition for pollutants. The degradation pathway of azo dyes was analyzed by UV–Vis, FTIR and MS. According to the examined results, the hydroxyl ( OH) radicals induced strong oxidizing effects in the target solution and destroyed the chromophoric groups of azo-benzene conjugated of the molecular structure. Considering characteristics of the dye structure, the azo bond (h name="dbnd" />Nirst be attacked by the hydroxyl radical and other free radicals. With the continuous oxidization and the long reaction time at high temperature, these intermediates could be oxidized to the final oxidation products, such as water and carbon dioxide. [Copyright &y& Elsevier]

Abstract: This paper investigates the well-to-wake energy consumption and greenhouse gas emissions of several key SO X abatement options in marine transportation, ranging from the manufacture of low sulfur fuels to equipping the vessel with suitable scrubber solutions. The findings suggest that a scrubber system, used with current heavy fuel oils, has the potential to reduce SO X emissions with lower well-to-wake energy consumption and greenhouse gas emissions than switching to production of low sulfur fuels at the refinery. A sensitivity analysis covering a series of system parameters shows that variations in the well-to-tank greenhouse gas emissions intensity and the energy efficiency of the main engine have the highest impacts in terms of well-to-wake emissions. [Copyright &y& Elsevier]

This study reported a photoelectric co-catalyst system of jet-flow reactor for efficient mineralization of Bisphenol A (BPA), where H 2 O 2 was photoelectro-generated in situ from O 2 reduction on gas diffusion electrodes fabricated by nitrogen-doped porous carbon and graphitic carbon nitride (NPC/g-C 3 N 4). Current density, aeration rate, amount of MoS 2 and FeSO 4 catalyst in the jet-flow reactor photoelectrocatalysis system for BPA removal were investigated. The NPC/g-C 3 N 4 cathodes were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electron spin resonance (ESR), and the electrochemical workstation. The results show that at pH 7, the NPC/g–C 3 N 4 –(60%) has the highest rate of electrical generation hydrogen peroxide. When the pH rised, at pH values of 7, the cumulative of hydrogen peroxide increased, when the solution get slight alkaline, it was gradually decreased. Compared with the traditional electro-Fenton technology, the photoelectric method of co-catalysis has strong ·OH production rate and high oxidation ability. A possible mechanism for BPA degradation was oxidized by hydroxyl radical (·OH), resulting in the formation of shorter chain bisphenol A (BPA), which followed the same reaction cycle as BPA until it was mineralized. The removal rate of BPA can reach 100% within 20 min, the TOC removal rate up to 90%. This work provides new opinion into the development of a photoelectric collaborative system for H 2 O 2 generation and the fast BPA degradation. • NPC/g-N 3 C 4 electrode exhibit good photoelectrochemical properties under UV light irradiation. • During the degradation of bisphenol A, both electrocatalysis and photocatalysis produce a synergistic effect. • The functionalize mesoporous carbon electrode can effectively generate H 2 O 2 via photoelectrochemical reduction of O 2. [ABSTRACT FROM AUTHOR]

Efficient and sustainable treatment of real chromium-containing tannery sludge is attracting an increasing concern due to its potentially severe impacts on eco-system and human-beings. In this study, a greener alternative was studied for the removal and recovery of chromium from tannery sludge by ultrasound-assisted supercritical water oxidation approach. Supercritical water oxidation or ultrasonic treatment was respectively conducted to explore the detailed experiment parameters on organic destruction and chromium liberation. Ultrasound-assisted supercritical water oxidation treatment was then investigated to further explore the mechanism for Cr liberation. Experimental results indicate that supercritical water oxidation or ultrasonic treatment cannot effectively remove Cr from tannery sludge, while almost all Cr (99.6%) will be liberated to supernatant at optimized experimental conditions by ultrasound-assisted supercritical water oxidation treatment, with TOC removal efficiency over 99.9%. This indicates that toxic substances in sludge will be completely removed after ultrasound-assisted supercritical water oxidation treatment, and liberated Cr in the supernatant can be re-utilized after purification. This process is an efficient alternative for toxicity removal and chromium recovery from real tannery sludge contaminated by high concentration of Cr and refractory organics. • Ultrasonic assisted supercritical water oxidation approach is used for tannery sludge treatment. • About 99.9% COD and 99.6% Cr can be simultaneously removed or recovered. • UL pretreatment can facilitate TOC removal and Cr recovery during SCWO treatment. • Cr in sludge can be completely liberated and recovered as Cr 2 O 7 2− after SCWO treatment. [ABSTRACT FROM AUTHOR]

In this study, in-situ Fenton oxidation was used for the de-complexation and degradation of tannin-Cr(III) complexes. Cr(III) can be oxidized into free Cr(VI) under the effect of ·OH and oxidation products of tannin can be used as reductant for Cr(VI) to establish a redox cycle of Cr(III)–Cr(VI)–Cr(III). Thus, it is crucial to investigate the interactions of Cr(III) with tannin derived oxidation products due to negligible accumulation of Cr(VI) during Fenton oxidation treatment. Here, sequential filtration/ultrafiltration was applied to reveal the distribution characteristics of TOC and Cr fractions during the oxidation of tannin-Cr(III). As the increase of colloidal size of tannic acid products, residual TOC and Cr mainly distribute in larger size range after the oxidation of tannin-Cr(III) which can be ascribed to re-complexation between oxidation products and Cr(III). Besides, analytical results indicate that carboxyl group and hydroxyl group in oxidation products may cause the re-complexation of Cr(III), resulting in the formation of highly conjugated materials containing Cr(III). It can be concluded that due attention should be paid to the efficient removal technology and mechanism for polymer-Cr complexes, as well as the oxidation intermediates in the role of conversion and removal of Cr species. Image 1 • De-complexation and degradation of tannin-Cr(III) can be achieved by in-situ Fenton oxidation. • Fenton process cannot sufficiently oxidize high concentrated polyphenol-Cr complexes. • Cr(III) reduced from Cr(VI) can be complexed with degraded products of tannic acid. • AOPs can be effective route for treatment of concentrated organic wastewater enriched with Cr. [ABSTRACT FROM AUTHOR]

Abstract In this work, a new activated carbon fiber (ACF) cathode modified with graphitic carbon nitride (g-C 3 N 4) was developed, which enables the substantially improved production of H 2 O 2 (up to 32.8 mg L−1) with relatively low energy consumption (10.9 kWh kg−1) compared to generation without g-C 3 N 4 (4.09 mg L−1). The cathode was analyzed and characterized by scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction, and it was proved that the synthesized g-C 3 N 4 is a thin layer sheet with a large number of carbon particles and low defect porosity. The cathode manufacturing parameters were optimized, and the influences of H 2 O 2 production including the cathode potential, pH value, aeration rate and performance stability were studied. These features improved the production of H 2 O 2 by about more than 7 folds when optimized ratio of g-C 3 N 4 was used, and the modified cathode kept stable performance of H 2 O 2 generation in 5 cycles. Further discussed by linear sweep voltammetry, rotating disk electrode and contact angle analysis, the existence of g-C 3 N 4 were found to accelerate the electron transfer rate, is advantageous to the surface of the oxygen reaction, but will not change the two electronic number of oxygen reduction reaction activities, and this leads to enhanced performance of hydrogen peroxide production and the possible mechanism was suggested. Finally, the cathode improve by g-C 3 N 4 proved the degradation effect of phenol by photoelectric-Fenton process. Phenol was degraded completely, and 93.8% of the organic carbon was removed, which is more than 1.5 and 5 times the amount achieved using electro-Fenton and photo-Fenton degradation only. In the degradation process of phenol, electrocatalysis and photocatalysis, they were optimized to produce substantial synergistic effect, proving the great potential practical application of organic wastewater treatment. Highlights • g-C 3 N 4 /ACF electrode exhibit good photoelectrochemical properties under. • The functionalize carbon electrode can effectively generate H 2 O 2. • During the degradation process of phenol, electro- and photocatalysis support and optimize each other. [ABSTRACT FROM AUTHOR]

It is significant to recover metal values from spent lithium ion batteries (LIBs) for the alleviation or prevention of potential risks towards environmental pollution and public health, as well as for the conservation of valuable metals. Herein a hydrometallurgical process was proposed to explore the possibility for the leaching of different metals from waste cathodic materials (LiCoO 2 ) of spent LIBs using organics as reductant in sulfuric acid medium. According to the leaching results, about 98% Co and 96% Li can be leached under the optimal experimental conditions of reaction temperature - 95 °C, reaction time - 120 min, reductive agent dosage - 0.4 g/g, slurry density - 25 g/L, concentration of sulfuric acid-3 mol/L in H 2 SO 4  + glucose leaching system. Similar results (96% Co and 100% Li) can be obtained in H 2 SO 4  + sucrose leaching system under optimized leaching conditions. Despite a complete leaching of Li (∼100%), only 54% Co can be dissolved in the H 2 SO 4  + cellulose leaching system under optimized leaching conditions. Finally, different characterization methods, including UV–Vis, FT-IR, SEM and XRD, were employed for the tentative exploration of reductive leaching reactions using organic as reductant in sulfuric acid medium. All the leaching and characterization results confirm that both glucose and sucrose are effective reductants during leaching, while cellulose should be further degraded to organics with low molecular weights to achieve a satisfactory leaching performance. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the removal potential of polyacrylate in aqueous solution by activated sludge. Batch experiments investigated the effects of contact time, pH value, temperature, and concentration of adsorbate on polyacrylate removal by activated sludge to evaluate the isotherms, kinetics, thermodynamics, and mechanisms. The materials were characterized by N 2 adsorption-desorption isotherms, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FT-IR). The experimental results indicate that more than 90% of polyacrylate was removed by activated sludge in a short time. The adsorption capacity increase with the increase in initial polyacrylate concentration and temperature. Increasing pH value resulted in a decrease in adsorption capacity. The adsorption process fitted well to Langmuir isotherm and pseudo-second-order kinetic models. Thermodynamic parameters indicate that the adsorption of polyacrylate onto activated sludge was feasible, spontaneous, and endothermic. The results of kinetics, thermodynamics, SEM-EDS, and FT-IR showed that surface binding, hydrophobic interaction, and hydrogen bond force may play a major role in the removal process. Microbial community structure analysis by 16S rRNA gene revealed that short-term exposure with polyacrylate had a little negative impact on the activated sludge microorganisms. A better understanding of polyacrylate adsorption onto activated sludge is essential for improving predictions of the fate and transport of polyacrylate in waste water treatment process. [ABSTRACT FROM AUTHOR]

Designing efficient policies to mitigate the transport GHG emissions is pivotal to tackle climate change. Fuel economy standards with incentives for electric vehicles have been widely adopted in road transport to curb vehicle tailpipe emissions and encourage fleet technology transition. Using a fleet-based life cycle model for the passenger vehicle sector in China, we show that solely relying on tailpipe-based standards will not suffice to meet the sectoral goal of peaking its GHG emissions by 2030. Switching to a well-to-wheels based standard, in conjunction with complementary policy instruments to regulate the vehicle embedded emissions and low carbon fuel production, could effectively close the mitigation gap and achieve holistic GHG emissions reduction. Incorporating such life cycle assessment approaches into the regulatory framework should occur as soon as practicable to provide sufficient GHG emissions reduction so that the transport sector can contribute to the overall economy-wide carbon reduction commitment. [ABSTRACT FROM AUTHOR]

• Differences and similarities between ice and aqueous photochemistry were revealed. • Photodegradation kinetics are clearly influenced by the matrix phases, ice and water. • Different photodegradable potential orders between in the two phases were discovered. • Unidentical effects of key constituents in the two phases account for the differences. • Ice photolysis shows fewer products / simpler pathways compared to water photolysis. The photochemical behavior of organic pollutants in ice is poorly studied in comparison to aqueous photochemistry. Here we report a detailed comparison of ice and aqueous photodegradation of two representative OH-PAHs, 2-hydroxyfluorene (2-OHFL) and 9-hydroxyfluorene (9-OHFL), which are newly recognized contaminants in the wider environment including colder regions. Interestingly, their photodegradation kinetics were clearly influenced by whether they reside in ice or water. Under the same simulated solar irradiation (λ > 290 nm), OHFLs photodegraded faster in ice than in equivalent aqueous solutions and this was attributed to the specific concentration effect caused by freezing. Furthermore, the presence of dissolved constituents in ice also influenced photodegradation with 2-OHFL phototransforming the fastest in 'seawater' ice (k = (11.4 ± 1.0) × 10−2 min−1) followed by 'pure-water' ice ((8.7 ± 0.4) × 10−2 min−1) and 'freshwater' ice ((8.0 ± 0.7) × 10−2 min−1). The presence of dissolved constituents (specifically Cl−, NO 3 −, Fe(III) and humic acid) influences the phototransformation kinetics, either enhancing or suppressing phototransformation, but this is based on the quantity of the constituent present in the matrixes, the specific OHFL isomer and the matrix type (e.g., ice or aqueous solution). Careful derivation of key photointermediates was undertaken in both ice and water samples using tandem mass spectrometry. Ice phototransformation exhibited fewer by-products and 'simpler' pathways giving rise to a range of hydroxylated fluorenes and hydroxylated fluorenones in ice. These results are of importance when considering the fate of PAHs and OH-PAHs in cold regions and their persistence in sunlit ice. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Global temperature rise over the long term will be proportional to the total amount of CO2 emitted. Any given probability of exceeding a targeted maximum temperature rise implies a maximum limit on the cumulative total of CO2 that can be emitted: a CO2 “budget”. This paper describes an approach to modelling cumulative emissions from light and heavy duty road transport from the present to 2050, focussing on the USA and Europe, and comparing the potential impacts of a range of technological and behaviourally-based abatement measures with such cumulative emissions budgets. The model shows that abatement measures would have a lower effect on cumulative emissions from 2000 to 2050 than on annual emissions in 2050, so that focussing only on annual emissions could be misleading. It shows that technological developments would be insufficient on their own to enable Europe and the USA to meet CO2 budgets for road transport. Behavioural changes, which potentially can be implemented much sooner, would be essential too. There is potential to keep European light duty emissions very close to CO2 budgets, and US light duty emissions not far above the least restrictive budget, but the model predicts that heavy duty emissions in both regions are likely to exceed their CO2 budgets. Deeper emissions reductions in other regions and sectors will be needed to compensate for this. Timing would be critical: for the greatest impact, behaviour change policies and interventions would need to be applied early and deeply. [Copyright &y& Elsevier]

Highlights • Lithium can be selectively extracted using mild phosphoric acid. • High leaching efficiency can be obtained for lithium recovery. • Leaching of lithium is chemical/internal diffusion controlled reaction. • Lithium phosphate can be obtained after purification and precipitation. Abstract Extensive usage of different kinds of lithium ion batteries (LIBs) may result in a huge amount of complicated waste batteries stream, while insufficient attention has been paid on the selective recovery of lithium from these already complicated wastes. Herein, a novel approach was developed for the selective extraction of Li from mixed types of LIBs (LiCoO 2 , LiMn 2 O 4 , LiFePO 4 and LiCo 1/3 Mn 1/3 Ni 1/3 O 2) using mild phosphoric acid as efficient leaching agent. It can be concluded from leaching results that 100%, 92.86%, 97.57% and 98.94% Li can be selectively extracted from waste cathode materials of LiCoO 2 , LiMn 2 O 4 , LiFePO 4 and LiCo 1/3 Mn 1/3 Ni 1/3 O 2 , respectively, while transition metals (Co, Mn, Fe and Ni) can be hardly leached in mild acidic media under optimized leaching conditions. In addition, high selectivity coefficients (β Li/Me) can be obtained during the extraction of Li from other metals. It can be also discovered from characterization results (SEM, XRD, FT-IR and Raman spectra) that leaching residues are phosphate precipitates, which might be used for the recycling of other metals and preparation of cathode materials. Results from leaching kinetics indicate that the leaching of Li is chemical and internal diffusion controlled reaction, with apparent activation energy (Ea) of 37.74, 21.16, 27.47 and 21.86 kJ/mol for LiCoO 2 , LiMn 2 O 4 , LiFePO 4 and LiCo 1/3 Mn 1/3 Ni 1/3 O 2 , respectively. Finally, lithium phosphate with a purity of 98.4% can be obtained and the whole process can be efficient candidate for Li recovery with minor environmental impact and little waste produced. [ABSTRACT FROM AUTHOR]

The secure and harmless disposal for Cr-bearing tannery sludge (Cr-TS) has attracted an increasing concern, due to potentially adverse effect on ecosystem and human health. A greener alternative method about "waste treatment with waste" for thermally stabilizing real Cr-TS was developed via employing coal fly ash (CA) as dopants in this research. The co-heat treatment of Cr-TS and CA was carried out at the temperature range of 600–1200 °C to investigate the oxidation of Cr(III), immobilization of chromium and leaching risk of the sintered products, and the mechanism of chromium immobilization was further explored. The results indicate that the doping of CA can significantly inhibit the oxidation of Cr(III) and immobilize chromium by incorporating chromium into spinel and uvarovite microcrystal. At the temperature higher than 1000 °C, most of chromium can be converted into stable crystalline phases. Furthermore, a prolonged leaching test was conducted to study the leaching toxicity of chromium in sintered products, indicating that leaching content of chromium is much less than the regulatory limit. This process is a feasible and promising alternative for immobilization of chromium in Cr-TS. The research findings are supposed to offer a theoretical foundation and strategy choice for thermal stabilization of chromium, as well as safety and harmless disposal of Cr-containing hazardous waste. [Display omitted] • Real Cr-bearing tannery sludge and coal fly ash were thermally treated. • Doping coal fly ash can inhibit Cr(III) oxidation and promote Cr-crystal formation. • Cr can be securely immobilized in Cr-spinel and Uvarovite crystal above 1000 °C. • Leaching risk of Cr satisfies regulatory limit by a prolonged leaching experiment. • Tannery sludge can be detoxified and stabilized via "waste treatment with waste". [ABSTRACT FROM AUTHOR]

Various organic compounds extensively used in the leather industry could influence the performance of alkaline precipitation with Cr(III). This study focused on two typical Cr(III)-bearing complexes (Cr(III)-collagen and Cr(III)-citrate) ubiquitous in tannery effluent yet with distinct treatment efficiencies, as Cr(III) was much more difficult to remove in the Cr(III)-citrate solution. Comprehensive analytical methods were employed to explore the intrinsic mechanism. It was found that a lower removal efficiency towards Cr(III) was significantly associated with higher oligomers. The molecular size of the Cr(III)-citrate complex continued to increase with rising pH, making it larger overall than Cr(III)-collagen species. The growing oligomer moiety of dissolved Cr(III)-complex species could persist in the stronger basic pH range, leading to the large amount of residual Cr(III) in the Cr(III)-citrate system. Combining this result with potentiometric titration and X-ray photoelectron spectroscopy data, it was believed that the polymeric species other than monomers facilitated resisting the attack from hydroxide ions, and the postulated Cr(III)-citrate species towards higher oligomers were discovered. Beyond that, both charge neutralization and sweeping effects were presented among the gradually emerging flocs in the Cr(III)-collagen system together with the electric double layer compression effect derived from salinity, thus resulting in a larger floc size and higher Cr(III) removal efficiency in saline solutions. [ABSTRACT FROM AUTHOR]

Abstract: Tannic acid is known as one of the refractory organic pollutants in water. Amino-functionalized magnetic nanoadsorbent (Fe3O4@SiO2-NH2) exhibited high adsorption capacity for aqueous TA with maximum adsorption amount of 136.23mg/g at 25°C. TA adsorption on the adsorbent could be well described by Langmuir adsorption model and the adsorption process was endothermic. Furthermore, pseudo-second adsorption kinetics can fit TA adsorption data very well, and the adsorption rate decreased with increasing initial TA concentration. The presence of Na+, K+, and Ca2+ may result in enhanced TA adsorption. In addition, TA adsorption over the adsorbent was highly dependent on solution pH and the maximum adsorption amount was found to be at pH 6.0. The XPS analysis revealed that TA adsorption over the adsorbent may be attributed to the surface complexation between the amino groups of the adsorbent and TA in solution. The TA loaded adsorbent can be effectively desorbed in a 0.5M HCl solution, and the regenerated adsorbent can be recycled. [Copyright &y& Elsevier]

Abstract: A study of in-cylinder fuel–air mixing distributions in a firing gasoline-direct-injection engine is reported using planar laser-induced fluorescence (PLIF) imaging. A multi-component fuel synthesised from three pairs of components chosen to simulate light, medium and heavy fractions was seeded with one of three tracers, each chosen to co-evaporate with and thus follow one of the fractions, in order to account for differential volatility of such components in typical gasoline fuels. In order to make quantitative measurements of fuel–air ratio from PLIF images, initial calibration was by recording PLIF images of homogeneous fuel–air mixtures under similar conditions of in-cylinder temperature and pressure using a re-circulation loop and a motored engine. This calibration method was found to be affected by two significant factors. Firstly, calibration was affected by variation of signal collection efficiency arising from build-up of absorbing deposits on the windows during firing cycles, which are not present under motored conditions. Secondly, the effects of residual exhaust gas present in the firing engine were not accounted for using a calibration loop with a motored engine. In order to account for these factors a novel method of PLIF calibration is presented whereby ‘bookend’ calibration measurements for each tracer separately are performed under firing conditions, utilising injection into a large upstream heated plenum to promote the formation of homogeneous in-cylinder mixtures. These calibration datasets contain sufficient information to not only characterise the quantum efficiency of each tracer during a typical engine cycle, but also monitor imaging efficiency, and, importantly, account for the impact of exhaust gas residuals (EGR). By use of this method EGR is identified as a significant factor in quantitative PLIF for fuel mixing diagnostics in firing engines. The effects of cyclic variation in fuel concentration on burn rate are analysed for different fuel injection strategies. Finally, mixture distributions for late injection obtained using quantitative PLIF are compared to predictions of computational fluid dynamics calculations. [Copyright &y& Elsevier]

Efficient recycling of valuable components, especially high value-added parts, from spent lithium ion batteries (LIBs) is of great importance to alleviate or avert current environment-related issues and growing resources depletion. Current study established a novel process for in-situ separation and recycling of both coating materials and Al foils from spent LIBs using ultrasonic-assisted acid scrubbing method. Waste cathodes obtained after pretreatment were cut into smaller pieces, put into a self-designed ultrasonic reactor and immersed in different aqueous solutions for scrubbing experiments. Experimental data proves that acidic solutions (i.e. sulfuric and oxalic acidic media), even quite dilute solutions, can significantly improve peeling off efficiency and Al purity, instead of pure water ultrasonic scrubbing. About 99%, 100% and 46% coating materials can be detached in sulfuric acidic, oxalic acidic and pure water medium, respectively, leaving these Al foils with a corresponding purity of 98%, 99% and 15%. The possible cause for the prompt peeling off coating materials may be rapid degradation of binders by the strong oxidation of HO· radicals formed and strengthened in acidic ultrasonic solutions. Net profits of $2.587 or $2.043 per kg spent batteries can be achieved in sulfuric or oxalic acidic ultrasonic scrubbing system. This recycling process may suggest an alternative for in-situ recycling of cathode materials and Al foils from spent LIBs, with simplified separation procedure and enhanced recycling efficiency and product purity. Synopsis: HO· radicals formed in mild acidic ultrasonic solutions can facilitate the prompt degradation of PVDF binder for subsequent in-situ recycling of Al foils and cathode materials. Image 1 • Ultrasonic-assisted acid scrubbing is applied during the exfoliation process. • Cathode materials and Al foils can be in-situ recovered as their original forms. • High purity products can be simultaneously obtained under optimized conditions. • Prompt exfoliation may attributed to HO· formed in acidic ultrasonic solution. [ABSTRACT FROM AUTHOR]