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Landfill leachate contains large amounts of non-biodegradable organic matter. The recalcitrant substances become more concentrated following the treatment using a combination of biological methods and nanofiltration. In this study, the nanofiltration concentrated landfill leachate (NCLL) was subjected to coagulation treatment using the bipolar membrane electrodialysis (BMED) process with iron tailings. The H+ required for metal leaching and OH− for coagulation are supplemented by water dissociation. The pH value of the NCLL played an important role for coagulation and the suitable pH value was 4. As the resource of the coagulant, a certain amount of iron tailing is needed. The energy consumption (EC) for chemical oxygen demand (COD) removal was about 0.70 kW h/g COD with 10 g tailing. Pretreating the tailing with 0.2 mol/L HNO 3 could enhance the coagulation process, resulting in a COD removal ratio of 67.3% within 4 h. Increasing the current density improved the COD removal rate, but consumed more electricity. Employing more treatment units is a viable approach to reduce EC. It decreased to 0.045 kW h/g COD when two treatment units connected together. Humic like acids and fulvic like acids present in the NCLL have been effectively removed. This study provides a way of 'treating the wastes with wastes' for NCLL treatment. [Display omitted] • BMED systems were employed to treat landfill leachate using iron tailings. • H+ for metal leaching and OH− for coagulation are provided by water splitting. • The COD removal rate of the landfill leachate reach to 67.3 % within 4 h. • Connecting more treatment units could reduce the energy consumption. • The EC was about 0.045 kW h/g when two treatment units connected in series. [ABSTRACT FROM AUTHOR]

[Display omitted] • Magnesite tailings and wastewater were resource utilization by the BMED process. • H+ for Mg leaching and OH– for struvite formation are provided by water splitting. • The P recovery ratios can reach approximately 98% under various conditions. • The nitrogen (NH 4 +-N) was recovered as struvite instead of being released. • The purity of struvite can reach as high as 97.1%. In this study, the feasibility of simultaneously recovering Mg, nitrogen (NH 4 -N) and phosphorus (P) from magnesite tailings and freshwater aquaculture have been confirmed through the bipolar membrane electrodialysis with a processing unit for the first time. The H+ required for Mg2+ leaching and OH– needed for struvite formation can be provided by the BMED system. The results indicate that adding 0.3 mol/L initial HNO 3 could enhance the Mg2+ leaching and reduce the energy consumption (EC). The recovery ratios of P and NH 4 -N reached to about 97.9 % and 52.3 %, respectively, while the EC was about 0.051 kWh/L. Increasing the tailing dosage shortened the required treatment time and reduced the EC. Increasing the current density significantly enhanced nutrient recovery rate, but accompanied by an increase in EC. A longer treatment time is necessary for treating larger volumes of wastewater, while a P recovery ratio of approximately 99 % can be achieved. Calcium is the predominant impurity. The purity of struvite was enhanced through a multi-batch process, achieving a maximum of 97.1 % at the third time. This study provides new insights into the resourceful treatment of tailings and wastewater. [ABSTRACT FROM AUTHOR]

To realize an efficient solar disinfection, Z-scheme In 2 O 3 /g-C 3 N 4 heterojunctions were prepared and its performances were investigated. The In 2 O 3 /g-C 3 N 4 exhibits a wide light response range and a low carrier recombination rate. Due to the transfer of electron (e-) and hole (h+) between In 2 O 3 and g-C 3 N 4 , the generations of superoxide (O 2 •-) and hydroxyl radicals (HO•) were enhanced. O 2 • − , HO• and h+ played important roles for disinfection. Approximately 106 CFU/mL E. coli were inactivated within 90 min. In addition to cell membrane lysis, DNA was degraded. In 2 O 3 /g-C 3 N 4 still revealed high sterilization efficiencies under natural sunlight or for actual wastewater treatment. Although humic acid and inorganic anions (Cl‾ < NO 3 ‾ < SO 4 2‾ < H 2 PO 4 ‾ < HCO 3 ‾) inhibited the disinfection, detection limit (DL, about 5.8-log removal) can be achieved. Furthermore, DL still could be achieved and the In 2 O 3 /g-C 3 N 4 structure remained intact after 5 cycles. This study provides novel guidance for solar-driven water purification. [Display omitted] • A novel Z-scheme In 2 O 3 /g-C 3 N 4 heterojunction was prepared and used for disinfection. • The band gap of g-C 3 N 4 was reduced from 2.67 to 2.53 eV via doping In 2 O 3. • A 5.8-log removal was achieved within 90 min under sunlight with 10% In 2 O 3 /g-C 3 N 4. • h+, • O 2 − and •OH played important roles and E. coli was completely inactivated. • The In 2 O 3 /g-C 3 N 4 exhibited satisfied performance for various real water disinfection. [ABSTRACT FROM AUTHOR]

Abstract A reticulated vitreous carbon (RVC) cathode modified by anodic polarization in 20 wt% H 2 SO 4 solution was used for drinking water disinfection under a neutral low electrolyte concentration (0.25 g/L Na 2 SO 4) condition. The contribution of the modified RVC anode and the Ti/RuO 2 cathode to disinfection was investigated. The influences of current, initial Escherichia coli load, temperature and water volume were studied. The results show that H 2 O 2 generation increased to approximately three times using the modification of the RVC. E. coli was mainly deactivated by the H 2 O 2 generated at the cathode. For water with about 106 CFU/mL E. coli , the detection limit (<4 CFU/mL) was reached under different conditions. Increasing current could simultaneously shorten the treatment time and increase the energy consumption (EC) simultaneously. Although decreasing the initial load reduced the treatment time, the EC for per log E. coli removal increased. The time required for disinfection shortened from 3.5 to 2.5 h and the EC for per log removal decreased from 218.5 to 123.2 Wh/m3 when the temperature increased from 20 to 40 °C. Although more time was required for disinfection, the EC decreased from 218.5 to 141.4 Wh/m3 when the volume was doubled. Highlights • E. coli was inactivated in neutral lower salinity electrolyte (0.25 g/L Na 2 SO 4). • Modified RVC cathode was the main contributor for disinfection. • The anodic polarization of RVC could enhance H 2 O 2 generation. • Raising temperature could enhance the disinfection process. • The energy required for disinfection was 218.5 Wh/m3 at 20 °C. [ABSTRACT FROM AUTHOR]

Background: Streptomyces lincolnensis is well known for producing the clinically important antimicrobial agent lincomycin. The synthetic and regulatory mechanisms on lincomycin biosynthesis have been deeply explored in recent years. However, the regulation involved in primary metabolism have not been fully addressed. Results: SLCG_7083 protein contains a Per-Arnt-Sim (PAS) domain at the N-terminus, whose homologous proteins are highly distributed in Streptomyces. The inactivation of the SLCG_7083 gene indicated that SLCG_7083 promotes glucose utilization, slows mycelial growth and affects sporulation in S. lincolnensis. Comparative transcriptomic analysis further revealed that SLCG_7083 represses eight genes involved in sporulation, cell division and lipid metabolism, and activates two genes involved in carbon metabolism. Conclusions: SLCG_7083 is a PAS domain-containing regulator on morphological development and glucose utilization in S. lincolnensis. Our results first revealed the regulatory function of SLCG_7083, and shed new light on the transcriptional effects of SLCG_7083-like family proteins in Streptomyces. [ABSTRACT FROM AUTHOR]

A magnesium anode seawater battery system was built for recovering NH 4 -N (ammonium) and P (phosphorus) from mariculture wastewater for the first time. The Mg 2+ needed for struvite formation was provided by the anode corrosion. The performances of the system were investigated by the struvite crystallization and electricity generation at different conditions. The results show that the pH value of the wastewater was rapidly increased to pH 9 and stable at about pH 10 by the seawater battery without adjusting pH. The pH range was suitable for struvite crystallization. Satisfied P recovery was achieved and it was about 99% at different conditions. The struvite formation was increased with increasing the P:N molar ratio and 1:1 was found to be suitable for enhancing the struvite crystallization. The recovery ratios of the NH 4 -N and P were 37.37% and 98.99%, and the residual concentrations of them were 14.09 and 0.55 mg/L, respectively. The optimum pH value was pH 9 and the NH 4 -N recovery was 48.07% at this pH condition. Increasing temperature could shorten the time needed for recoveries in the range from 15 °C to 35 °C. Expanding the magnesium anode area was benefit for the recovery. Increasing temperature or expanding the anode area could improve the electricity generation. The seawater battery could supply relatively stable electricity, and it was 20 mW during the process treating 0.9 L mariculture wastewater. Our results suggest that the seawater battery system is a possible approach for simultaneous NH 4 -N and P recovery and electricity production from wastewater. [ABSTRACT FROM AUTHOR]

A new hybrid system that integrated a photovoltaic (PV) panel with a solar photo-Fenton (SPF) reactor was constructed to treat wastewater and generate electricity for the first time. The decolorization and photovoltaic performances of the hybrid system were tested outdoors by discoloring three dyes: Acid Red 26 (AR26), Malachite Green (MG) and Reactive Blue 4 (RB4). Lab scale experiments also had been done to confirm the impact of temperature on the SPF process. The lab scale results show that SPF process was more efficiency for decoloring the different dyes, compared with dark Fenton. The SPF followed a pseudo-first-order reaction and the reaction rate constant was improved about 3.5, 4.5 and 0.61 times for AR26, RB4 and MG respectively as the wastewater temperature increased from 20 to 50 °C. The decolorization difficulty of the three dyes followed this order: MG > AR26 > RB4. The results of the hybrid systems tested outdoors show that 200 mg/L MG had achieved 98.6% color removal after 3 h of treatment at a low catalyst dose (Fe 2+ = 5 mg/L) under sunlight. For 100 mg/L MG, 99.3% color removal was observed after 70 min. The treatment time required for decolorization of AR26 and RB4 was more shorter. In the present of the water layer, the wastewater temperature was increased and that of the hybrid system was decreased. The average output power of the hybrid system was more than 12 W and sufficient to drive the system during all of the outdoor experiments. Our results suggest that the system could realize decolorization of different dyes and automatic operation. [ABSTRACT FROM AUTHOR]

The objective of the study is to construct and evaluate a fixed PV (photovoltaic) cell integrated with SODIS (solar water disinfection) system to treat drinking water and generate electricity under different climate through experimental and simulation methods. The photovoltaic and disinfection performances of the hybrid system were studied by the disinfection of Escherichia coli . The applicability of the system in Lhasa and Chennai was evaluated by analyzing the daily radiation and predicting the daily water temperature and the system electricity output. The results confirm that the temperature would dramatically enhance the SODIS process and shorten the disinfection time, when the water temperature was above 45 °C. The PV cell in the hybrid system could work under low temperature because of the water layer and the generated electricity was much more than the system consumption. The simulation results show that the days with maximum water temperature above 45 °C were more than 60% of whole year in Chennai. The generated electricity of the hybrid system was 49682.3 W h and 45615.9 W h a year in Lhasa and Chennai respectively. It was sufficient to drive the system of whole year. The number of days which realized drinking water treatment was 324 days in Lhasa and 315 days in Chennai a year. [ABSTRACT FROM AUTHOR]

In this study, the UVA (Ultraviolet A) drinking water disinfection was promoted by electrolysis. The influences of the UVA, electrolysis current, bubbling and temperature were investigated. The disinfection mechanisms and bacterial reactivation had been studied. The results revealed that the treatment time needed to reach the DL (detection limit, about 5.4 log removal) was shortened from 180 to 80 min by the electrolysis. The total electricity consumption decreased from about 126–57.0 kJ/L. Compared with increasing the UVA irradiation, increasing the electrolysis current in a certain range was more preferred to improve the disinfection rate. Oxygen bubbling or higher temperature could enhance the E. coli inactivation. The quenching experiment and EPR (Electron paramagnetic resonance) detection confirmed that ROSs (1O 2 , ·O 2 - and ·OH) played important roles for the disinfection. Compared with the treatment with UVA alone, the cell membrane damage was more severe by the promoting method. In addition to the dramatically reduced enzyme activity, the synergistic process degraded most of the bacterial genomic DNA, and the bacteria were completely killed. Therefore, hybrid with electrolysis is a better way for the application of the UVA-LED disinfection. [Display omitted] • The electricity consumption was reduced sharply by the electrolysis promotion. • The promoting process degraded most of the bacterial genomic DNA. • 1O 2 , ·O 2 - and ·OH played critical roles in the disinfection. • Complete disinfection was achieved within 80 min under certain conditions. • The promoting process avoided the bacterial reactivation. [ABSTRACT FROM AUTHOR]

It is the first time that flat PV (photovoltaic) cells were integrated with SODIS (solar water disinfection) to be an access to the clean drinkable water and the renewable electricity. The disinfection and photovoltaic performance of the system was evaluated by the disinfection of Escherichia coli ( E. coli ) and Salmonella . In order to enhance the SODIS process, a V-trough concentrator and low concentration H 2 O 2 were adopted. The treatment time required for 8 L water that reached completely disinfection was 1.25 h and 2.5 h for the inactivation of E. coli and Salmonella respectively, when using the V-trough concentrator and 5 mg L −1 H 2 O 2 simultaneously. Therefore, E. coli seems not to be a suitable bacteria indicator for SODIS. The temperature of the PV module decreases significantly because of the additional water layer, so that the power generation efficiency is improved. Although the water layer on the PV module can both reflect and absorb light, the output power of the PV module with a V-trough concentrator is about 43 W (the reference is 26.1 W), which is much higher than the whole system power consumption. Therefore, the excess power can be used for other applications. [ABSTRACT FROM AUTHOR]

Aquaculture wastewater contained large amounts of pathogenic microorganisms, nitrogen (N) and phosphorus (P). In this study, the nutrient recoveries and wastewater disinfection were simultaneously achieved using Mg–coconut shell carbon (Mg–CSC). The composites were prepared by a ball milling method. The hydrogen peroxide (H 2 O 2) was in-situ generated by the dissolved oxygen reduction driven by Mg corrosion on the CSC surface, which inactivated the microorganisms. Besides that, Mg corrosion provided sufficient Mg ions and appropriate pH conditions for struvite formation. The results show that 5.4-log E.coli removal was achieved under different conditions. Improving the Mg/CSC ratio and composite dosage could shorten the time required for disinfection. In addition to H 2 O 2 , singlet oxygen played a critical role. Reactive oxygen species destroyed the cellular structure and killed the bacteria. The recoveries of NH 4 + - N and P under certain conditions were about 60% and 91%, respectively. An increased composite dosage could improve the recovery ratio of P. Excessive dosages were not beneficial for removing NH 4 + - N. The characterization result revealed that struvite crystals were the main precipitates on the CSC surface. The Mg–CSC composites also revealed satisfied nutrient recovery and disinfection performances in the real aquaculture wastewater treatment process. [Display omitted] • Mg–CSC could simultaneously kill bacteria and produce struvite. • The nutrients recovery and disinfection process are spontaneous. • Except H 2 O 2 , 1O 2 played a critical role in the disinfection. • Complete disinfection was achieved within 4 h under certain conditions. • The recovery ratio of phosphorus was more than 90%. [ABSTRACT FROM AUTHOR]

• 1O 2 was the main ROS, which played an important role for the disinfection. • The inactivation time reduced by 40 %, compared with SODIS. • Total inactivation by eletro/SODIS was achieved within 180 min. • High concentration of HA or bicarbonate increased the treatment time. • This method can be powered by a common alkaline battery and is feasible to use. In this study, the solar water disinfection (SODIS) process was enhanced by in situ generated H 2 O 2 , and the influences of current, temperature, bacterial load, humic acid (HA), and bicarbonate were investigated. The results revealed that 1.29 kJ/L of electricity consumption reduced the treatment time by 40 % and decreased the required solar energy from 235.95–141.58 kJ/L. 1O 2 was the main reactive oxygen species (ROS), which played an important role. Increasing the current from 15 to 25 mA improved the cumulative H 2 O 2 production, but it had no effect on the disinfection rate. Bicarbonate markedly suppressed E. coli inactivation. Decreasing the initial E. coli concentration reduced the required treatment time from 180 to 120 min. Increasing the temperature had a positive effect on the disinfection. HA concentration of 1 mg/L was the best for E. coli inactivation. In the presence of higher HA concentrations, it required a longer treatment time. [ABSTRACT FROM AUTHOR]

Long treatment times limit the application of solar disinfection (SODIS). The concentrations of electrolytes in drinking water are low, so it is difficult to generate a sufficient quantity of H 2 O 2 for drinking water disinfection via electrochemical reduction. In this study, SODIS and electrochemical reduction were combined together. A reticulated vitreous carbon (RVC) cathode was anodised to improve its performance and characterized using scanning electron microscopy and X-ray photoelectron spectroscopy. The contributions of the electrochemical process and SODIS to disinfection were studied. The influences of current, temperature and humic acid (HA) were also investigated. The results showed that the modification of RVC added oxygen-bearing functional groups and doubled the quantity of H 2 O 2 generated at the cathode. When the hybrid process was employed to remove E. coli from water, The E. coli count was reduced from approximately 106 colony-forming units (CFUs) per mL to below the detection threshold (<4 CFU/mL) after 120 min. The disinfection time of the hybrid method was lower than those of SODIS and electrochemical disinfection alone by 60% and 20%, respectively. Increasing the current reduced the treatment time from 150 to 90 min, although the treatment consumed more electricity. HA in a low concentration (1 mg/L) could enhance the disinfection process. However, a relatively high HA concentration (4 mg/L) suppressed the inactivation of E. coli. Increasing the temperature from 20 to 40 °C reduced the treatment time from 120 to 90 min, and the electricity consumption per log of E. coli decreased from 102.2 to 64 Wh/m3. This study demonstrates that combining SODIS and H 2 O 2 electrogeneration is an effective and energy-efficient disinfection strategy. • Disinfection rate was increased by combining hydrogen peroxide with sunlight. • The influence of humic acid on disinfection was determined. • Raising temperature reduced the treatment time and the electricity consumption. • The electricity consumption for per log E. coli removal was 102.2 Wh/m3 at 20 °C. [ABSTRACT FROM AUTHOR]

The material surface was sinusoidally textured using nanosecond laser processing technology, and Ni-based MoS2 coatings were applied to the resultant surfaces via plasma spray. The adhesion of the coating was investigated through separate adhesion tests to assess the impact of retaining the fusion-sputtered splash bulges and subsequently grinding them off. The coating's cross-sectional microstructure and fracture morphology were characterized to investigate its deposition and fracture mechanisms. The comparison of textured surfaces with and without bulges has shown that the exposed plain areas diminish the coating's adhesion. Furthermore, the splash bulge also significantly affects the adhesion. Fracture analysis has demonstrated that the mixed failure mode is dominated by no uplift, and adhesive failure occurs in practically all plain areas. By analyzing specimen cross-sectional morphologies and extracting coating morphological features in and around the splash bulge, several aspects, such as filling and spreading mode, the state of sprayed droplets, porosity comparison, and crack formation mechanism and distribution, were investigated. Finally, it was concluded that the excessive or large splash bulges detrimentally impact the bonding properties of the coating. [ABSTRACT FROM AUTHOR]

The bonding of thermal-sprayed coatings largely depends on the substrate surface morphology. This study examines the effect of the substrate surface texture shapes on the adhesion strength of coatings. For that, it used plasma-sprayed Ni-based MoS2 coatings deposited on grit-blasted and laser-textured surfaces, and investigated the coating bonding strength (ASTM 633 pull-off test), and cross-sectional and fracture morphologies, as well as phase compositions and element distribution. The results showed that the surface texture shape has a significant effect on the improvement of coating adhesion. The coatings deposited on sinusoidal-textured surfaces had the highest adhesion strength (50.0 MPa), followed by coatings deposited on groove-textured surfaces, while dimple and dimple–groove textures resulted in the lowest coating adhesion strength. The coating fracture analysis revealed that cohesive failure occurred mainly at the texture positions, while adhesive failure occurred almost always in plain areas. Therefore, it could be concluded that, in the conditions of this study, the existence of plain areas and dimple textures did not improve coating adhesion. Factors such as coating bond mode, contact area ratio, and coating deposition quality should be comprehensively considered in texture design to improve coating adhesion. [ABSTRACT FROM AUTHOR]

In this study, the thermal and mechanical behaviors were investigated by simulating laser remelting of atmospheric plasma‐sprayed yttria‐stabilized zirconia coatings, and the molten depth and regions of stress concentration were compared between simulation and experiment. The heat treatment process of the remelted coating was also simulated. The crack formation mechanism in the YSZ coating remelted by laser and the heat‐treatment effect on residual stress were investigated. Results showed that the simulated results were consistent with the experimental measurements, and the residual thermal stress was the main cause of cracks formation. The coating remelted by a laser power of 1500 W and a scanning rate of 9 mm/s possessed less residual concentrated stress and segmented cracks. Heat treatment released concentrated stress, which was still accurate for the ceramic coating. If the coatings were slowly heated to demonstrate heat treatment after laser remelting, the cracks in the remelted layer decreased correspondingly. [ABSTRACT FROM AUTHOR]

Abstract An electrokinetic (EK) system improved by a bipolar membrane (BPM) (BPM-EK) was used to recycle hexavalent chromium (Cr(VI)) from the chromite ore processing residual (COPR) in the form of H 2 CrO 4. The results showed that electrolyte concentrations in anode chamber (AC) and cathode chamber (CC) influenced the cell voltage and that 0.6 mol/L HNO 3 in the AC and 1.0 mol/L NaNO 3 in the CC were the optimal electrolyte concentrations. The current density also affected cell voltage, pH value of the COPR chamber (COPRC), Cr(VI) recovery efficiency, current efficiency (CE), and specific energy consumption (SEC). The optimal current density was 3.0 mA/cm2. Compared to traditional EK processes, a higher CE and a lower SEC were obtained when two and three COPRC were equipped in the BPM-EK system and the Cr(VI) recovery efficiencies of all COPRCs were higher than 82%. With the increase in the number of equipped COPRC from one to two and three, CE increased from 0.60% to 1.67% and 2.30% and SEC decreased from 0.906 to 0.433 and 0.395 kW h/g, respectively. Experimental results showed that the BPM-EK process is an effective method for the recovery of Cr(VI) from COPR. Graphical abstract fx1 Highlights • An improved electrokinetic system was used to recycle Cr(VI) from the COPR. • The current density had some effects on the cell voltage and COPR pH. • The recovery efficiency of Cr(VI) in different system was higher than 82.0%. • The CE increased and the SEC decreased in more COPRCs equipped system. [ABSTRACT FROM AUTHOR]

This study presents a new solar-driven hybrid system that integrated a photo-electrochemical reactor with a photovoltaics (PV) panel for azo dyes’ decolorization and electricity generation. Full spectrum of sunlight is utilized to optimize the color removal of Acid Red 26 (AR26) in this hybrid system. Persulfate (PS, S 2 O 4 2− ) was selected as the photochemical oxidant and Ti/IrO 2 -Ta 2 O 5 electrode was used as the anode. Experiments were made to evaluate the efficiency of decolorization and the performance of PV panels in different reaction conditions outdoors. The results showed that the synergistic effect of two processes was observed for the AR26 decolorization. Comparing with the solar/persulfate process or the electrochemical process alone, the complete color removal time by the hybrid system decreased up to 50% and 44.4% respectively. In this system, the water layer in the flow channel cooled PV panels by absorbing the far infrared spectrum of sunlight, and the increased temperature of wastewater from 7 °C to 16 °C enhanced the decolorization efficiency of AR26. Moreover, the generated electricity by PV panels could satisfy the energy demand of electrochemical oxidation. [ABSTRACT FROM AUTHOR]

To reduce the power energy consumption of wastewater treatment and make full use of the solar spectrum, a new water purification system that integrated homogeneous solar photochemical (SPC) and photovoltaics (PV) was constructed to treat wastewater and generate electricity for the first time. Hydrogen peroxide (H 2 O 2 ) and potassium persulfate (K 2 S 2 O 8 ) were chosen as oxidants in the system and have a comparative analysis. The results show that solar/K 2 S 2 O 8 has a higher decolorization efficiency than solar/H 2 O 2 , the accumulated ultraviolet energy in solar/K 2 S 2 O 8 , needed for complete decolorization, is far lower than in solar/H 2 O 2 . Also temperature has a positive effect on the dark-K 2 S 2 O 8 processes especially in the range of 40–60 °C, and it follows pseudo-first-order kinetic relationship. Meanwhile, to investigate the influence of flow channel on PV, the short circuit current ( I sc ) and maximum output power ( P m ) were monitored. It indicates that the presence of flow channel effectively decreases the working temperature of PV modules, while the I sc and P m have a different degree reduce. Luckily, the impact is not big. Additionally, P m in experiment system, though lower than reference system, is sufficient to drive the whole system. [ABSTRACT FROM AUTHOR]

To increase the photocatalytic reaction rate and make full use of electricity generated by photovoltaics (PV), a water purification system (SOL&PID) with solar and ultraviolet-light emitting diode (UV-LED) powered by a hybrid PV photocatalytic reactor was designed and tested in this paper. The SOL&PID system is based on Solar Water Purification and Renewable Electricity Generation system (SOLWAT). Photovoltaic and photocatalytic performances of SOL&PID system were evaluated in comparison with SOLWAT by the degradation of Acid Red 26 (AR 26) and 4-chlorophenol (4-CP) using suspended TiO 2 . To assess the directly-coupled performance between PV and UV-LED array, the power consumption percentage of UV-LED array from the maximum output power of PV was analyzed. The results show an adequate coupling between the UV-LED array and the photovoltaics. More than 92% of the maximum output power generated by PV modules is used to drive the LED array. The photocatalytic reaction rate constants in SOL&PID system increase respectively 29–37% and 31–78% during AR 26 and 4-CP experiments, in comparison with SOLWAT system. Besides, the SOL&PID system achieved lower solar module temperature and lower UV-LED pin temperature than the reference systems by the addition of flow channel. [ABSTRACT FROM AUTHOR]

Electroless nickel-plating (ENP) wastewater is challenging to treat because of its complex composition. This study used bipolar membrane electrodialysis (BMED) to remove and recover Ni2+, NH 4 +, total phosphorus (TP) and NO 3 − from ENP wastewater. The results show that current density significantly affects ion removal and recovery, current efficiency, specific energy consumption and ion migration velocity. When the current density was 20 mA/cm2, the removal ratios of Ni2+, NH 4 +, TP and NO 3 − were 100%, 98.6%, 99.3% and 100% after 14 h, respectively, and their recovery ratios were 92.6%, 75.5%, 94.5% and 90.6%, respectively. The removal kinetics analysis showed that the removal of Ni2+, NH 4 +, TP and NO 3 − was consistent with the zero-order kinetics process. The current efficiency variated from 42.5% to 39.0% and 37.7%, and the specific energy consumption decreased from 1.67 to 1.38 and 1.32 kW h/mol with the equipped wastewater compartments increased from one to two and three in a BMED system. Post treatment, Ni2+ was recovered as Ni(OH) 2 , with a purity of 82.6% (commercial Ni(OH) 2 purity = 90%). TP was recovered as struvite with a purity of 95.3%, and the physicochemical properties of the obtained struvite were similar to commercial struvite. NH 4 + was recovered as (NH 4) 2 SO 4 and NH 3 •H 2 O. Therefore, BMED is an effective method to recover Ni2+, TP and NH 4 + from ENP wastewater. [Display omitted] • Electroless nickel-plating wastewater was treated using a BMED system. • Ni2+ was recovered in the form of Ni(OH) 2 with a purity of 82.6%. • Total phosphorus was recovered in the form of struvite with a purity of 95.3%. • NH 4 + was recovered in the form of (NH 4) 2 SO 4 and NH 3.•H 2 O. [ABSTRACT FROM AUTHOR]

An efficient and thorough water disinfection is critical for human health. In this study, UVA-LEDs, nitrilotriacetic acid (NTA) and a boron-doped diamond anode were respectively used as the UVA source, the iron chelator and the anode for the UVA/electro-Fenton (E-Fenton) reaction to treat wastewater. The disinfection performance of the UVA/E-Fenton had been investigated. The mechanisms of the E. coli inactivation had been clarified. The results showed that complete disinfection (about 5.6-log removal) could be achieved within 50 min at a certain condition due to the synergistic effort of the UVA, anodic oxidation and the electro-Fenton. The quenching experiments and the electron paramagnetic resonance (EPR) detection indicated that •OH, • O 2 − and 1O 2 play important roles for inactivating E. coli. The results of SEM images and genomic DNA electrophoresis suggested that both the cell structure and the DNA had been thoroughly destroyed during the UVA/E-Fenton process. Increasing the UVA irradiation, oxygen bubbling could improve the disinfection rate, while it also would increase the energy consumption. The appropriate Fe and NTA ratio was 1:2 to realize an efficient Fenton reaction under near neutral condition. Complete disinfection was also achieved within 50 min when it used for treating real wastewater. Thus, the UVA/E-Fenton process is a satisfied way for water disinfection. [Display omitted] • Both the cell structure and the bacterial genomic DNA was completely destroyed. • Disinfection was achieved by the synergetic effort of UVA, BDD and electro-Fenton. • Complete disinfection was achieved within 50 min under certain conditions. • It revealed a satisfied performance in real wastewater disinfection. [ABSTRACT FROM AUTHOR]

[Display omitted] • A BMED system combined with H 2 O 2 oxidation was used to recover Cr(III) from soil. • About 98.9% of Cr(III) can be oxidized by H 2 O 2. • More than 69% of Cr(III) can be recovered in form of Na 2 CrO 4. • Variation of binding states of chromium before and after treatment was investigated. • Mechanism of recovering Cr(III) was analysed. When a bipolar membrane electrodialysis (BMED) system is used to remove Cr(III) from the soil, the existing metal cations easily affect this removal owing to the migration competition of metal cations. To address this problem, herein, a BMED system combined with H 2 O 2 oxidation was used to recover Cr(III) from soil in the form of Na 2 CrO 4. The experimental results show that H 2 O 2 can oxidise Cr(III) to Cr(VI), which can be recovered as Na 2 CrO 4. The concentrations of electrolyte and humic acid in soil, current densities and addition time of H 2 O 2 influenced Cr(III) recovery, current efficiency and specific energy consumption. Under optimal experimental conditions of a current density of 2 mA/cm2 and H 2 O 2 addition time of 2 h after the BMED system was powered on, more than 69 % of Cr(III) could be recovered. When the number of equipped soil compartments increased from one to two and then to three, the current efficiency increased from 9.9 % to 19.8 % and then to 29.1 % and the specific energy consumption of chromium removal decreased from 7.04 × 10−2 to 5.51 × 10−2 and then to 4.72 × 10−2 kW∙h/g, respectively. When the BMED system was used to recover Cr(III) from actual soil, the recovery rate decreased to 55.9 % owing to the low Cr(III) oxidation rate resulting from more residual state Cr(III) being present in actual soil. Following treatment, the remaining Cr(VI) in soil can be reduced to Cr(III) by adding a reductant. Therefore, the BMED system combined with H 2 O 2 oxidation can be regarded as an effective method for recovering Cr(III) from soil. [ABSTRACT FROM AUTHOR]

• Concentration electrodialysis (CED) was developed by combining ED and DD. • CED was used to selectively remove NH 4 +-N from high-salinity wastewater. • CED improved 32.3% and 13.3% removal rates compared to ED and DD, respectively. • CED reduced 14 h and 10 h to achieve the same removal percentages as ED and DD. • CED increased the current efficiency by 1.84 times compared with ED. In this study, a novel method, concentration electrodialysis (CED), was developed by combining conventional electrodialysis (ED) and Donnan dialysis (DD) effectively and selectively to separate NH 4 +-N from high-salinity wastewater. A high initial concentration of Na+ was provided in the cathode compartment to impede its competitive migration with NH 4 +. After optimization, the CED process removed up to 89.1% of NH 4 +-N from simulated high-salinity wastewater with an energy consumption of 0.51 × 10−3 KWh·mol−1. The initial brine concentration was the limiting factor for the removal percentage and rate. The maximum removal percentage was 13.3% and 32.3% higher than those of conventional ED and DD, respectively. CED shortened the time required to achieve the same final removal percentages achieved by conventional ED and DD by 14 h and 10 h, respectively. In addition, the current efficiency of CED was increased by 1.84 times greater than that of conventional ED, while reduced 50.48% of energy consumption. Moreover, the Na+ concentrations in the cathode and wastewater compartments both remained relatively constant, indicating that there was no need to add additional Na+ during the experimental process, which was beneficial for prolonging the experiment and reducing cost. Finally, the performance of CED in removing NH 4 +-N from actual maricultural wastewater further supported its potential for application in the future. [ABSTRACT FROM AUTHOR]

Ni based MoS 2 coatings were prepared on grit-blasted and bionic sinusoidal laser-textured surfaces by using an atmospheric plasma spray. The effects of bionic sinusoidal textures with different texture spacing and bulges on the adhesion strength of the coatings were investigated using the ASTM 633 adhesion test. The cross-sectional microstructure of the coatings and the fracture morphology were characterized to investigate the coating deposition and fracture mechanism. Results showed that the texture spacing and bulge significantly affect coating adhesion. Thus, the decrease in texture spacing and the existence of texture bulges significantly increased the adhesion strength. The comparison of textured surfaces with and without bulges showed that the exposed plain areas were harmful to the improvement of coating adhesion. An optimal texture spacing for coating adhesion improvement was observed for the textured surfaces with bulges. Fracture analysis showed that the mix failure mode mainly occurred without bulges, and adhesive failure occurred in almost all plain areas. With the existence of bulges, the adhesive failure only dominated when the texture spacing was very large or very small, otherwise, the fracture mechanism was dominated by cohesive failure. Unlabelled Image • A bionic sinusoidal texture is designed. • Effects of texture spacing and bulges on the coating adhesion are studied. • The decrease in texture spacing can remarkably enhance coating adhesion. • The removal of the bulges is harmful for the enhancement of coating adhesion • The existence of exposed plain areas is harmful to coating adhesion. [ABSTRACT FROM AUTHOR]

• A BMED system was used to removal heavy metals and recycle H 2 SO 4 from a raffinate. • The optimal current density and V RC :V HMC were 3.0 mA/cm2 and 1:15, respectively. • The raffinate can be used again as leaching influent after treatment. • The energy consumption decreased in more RCs equipped BMED system. • The H 2 SO 4 with the concentration of 0.395 mol/L was obtained in a-AC. The raffinate generated during copper ore hydrometallurgical processing is difficult to be treated because it is strongly acidic, and has high concentrations of heavy metals (Iron, Zinc, Copper etc). In this study, a bipolar membrane electrodialysis (BMED) system was studied for treatment of this challenging stream because in which salts can be converted into their corresponding acids and bases, which enables resource recovery in raffinate. The target was to reuse the raffinate as a leaching influent, to achieve zero discharge of wastewater. It was found that 85.9% of SO 4 2− in the raffinate could be recovered by the formation of H 2 SO 4. The removal rates of heavy metals were 99.3% (iron), 99.1% (zinc), 99.0% (copper), 84.9% (nickel), 70.6% (chromium), 95.8% (cadmium), and 94.8% (arsenic). The heavy metal cations were mainly removed in the heavy metals chamber (HMC) and anions were mainly removed in the acid compartment. A current density of 3.0 mA/cm2, a volume ratio between the raffinate chamber (RC) and the HMC 1:15, and a duration of 40 h were the optimal experimental parameters. Increasing the RC number from one to two and three increased the current efficiency from 54.0% to 106.9% (two) and 157.9% (three), and decreased the specific energy consumption from 0.160 to 0.108 and 0.089 kWh/L of raffinate. It was concluded that the raffinate can be used as a leaching solution after treatment and the studied BMED process is an effective technique for the treatment of raffinate. [ABSTRACT FROM AUTHOR]