Comprehensive utilization of phosphogypsum(PG)has attracted much attention,especially for the recovery of rare earth elements(REEs)and gypsum due to the issues of stockpile,environmental pollution,and waste of associa...Comprehensive utilization of phosphogypsum(PG)has attracted much attention,especially for the recovery of rare earth elements(REEs)and gypsum due to the issues of stockpile,environmental pollution,and waste of associated resources.Traditional utilization methods suffered the issues of low REEs leaching efficiency,huge amount of CaSO_(4)saturated wastewater and high recovery cost.To solve these issues,this study investigated the occurrence of REEs in PG and the leaching of REEs.The results show that REEs in PG are in the forms of(1)REEs mineral inclusions,(2)REEs isomorphous substitution of Ca^(2+)in gypsum lattice,(3)dispersed soluble REEs salts.Acid leaching results demonstrate that(1)the dissolution of gypsum matrix is the control factor of REEs leaching;(2)H_(2)SO_(4)is a promising leachant considering the recycle of leachate;(3)the gypsum matrix suffers a recrystallization during the acid leaching and releases the soluble REEs from PG to aqueous solution.For the recovery of the undissolved REEs mineral inclusions,wet sieving concentrated 37.1 wt%of the REEs in a 10.7 wt%mass,increasing REEs content from 309 to 1071 ppm.Finally,a green process combining gravity separation and hydrometallurgy is proposed.This process owns the merits of wastewater free,considerable REEs recovery(about 10%increase compared with traditional processes),excellent gypsum purification(>95 wt%CaSO_(4)·2H_(2)O,with<0.06 wt%of soluble P_(2)O_(5) and<0.015 wt%of soluble F)and reagent saving(about 2/3less reagent consumption than non-cyclical leaching).展开更多
The removal of ammonia nitrogen(NH_(4)^(+)-N)and bacteria from aquaculture wastewater holds paramount ecological and production significance.In this study,Pt/RuO_(2)/g-C_(3)N_(4)photocatalysts were prepared by deposit...The removal of ammonia nitrogen(NH_(4)^(+)-N)and bacteria from aquaculture wastewater holds paramount ecological and production significance.In this study,Pt/RuO_(2)/g-C_(3)N_(4)photocatalysts were prepared by depositing Pt and RuO_(2)particles onto g-C_(3)N_(4).The physicochemical properties of photocatalysts were explored by X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),X-ray diffraction(XRD),and UV–vis diffuse reflectance spectrometer(UV–vis DRS).The photocatalysts were then applied to the removal of both NH_(4)^(+)-N and bacteria from simulated mariculture wastewater.The results clarified that the removals of both NH_(4)^(+)-N and bacteria were in the sequence of g-C_(3)N_(4)<RuO_(2)/g-C_(3)N_(4)<Pt/g-C_(3)N_(4)<Pt/RuO_(2)/g-C_(3)N_(4).This magnificent photocatalytic ability of Pt/RuO_(2)/g-C_(3)N_(4)can be interpreted by the transfer of holes from g-C_(3)N_(4)to RuO_(2)to facilitate the in situ generation of HClO from Cl^(−)in wastewater,while Pt extracts photogenerated electrons for H_(2)formation to enhance the reaction.The removal of NH_(4)^(+)-N and disinfection effect were more pronounced in simulated seawater than in purewater.The removal efficiency ofNH_(4)^(+)-N increases with an increase in pH of wastewater,while the bactericidal effect was more significant under a lower pH in a pH range of 6–9.In actual seawater aquaculture wastewater,Pt/RuO_(2)/g-C_(3)N_(4)still exhibits effective removal efficiency of NH_(4)^(+)-N and bactericidal performance under sunlight.This study provides an alternative avenue for removement of NH_(4)^(+)-N and bacteria from saline waters under sunlight.展开更多
The kitchen-oil wastewater is characterized by a high concentration of organicmatter,complex composition and refractory pollutants,which make wastewater treatment more difficult.Based on the study of using micro-elect...The kitchen-oil wastewater is characterized by a high concentration of organicmatter,complex composition and refractory pollutants,which make wastewater treatment more difficult.Based on the study of using micro-electric field characteristic catalyst HCLL-S8-M to enhance the electron transfer between microorganisms in kitchen-oil wastewater which further improved the COD removal rate,we focus on themicrobial community,intracellular metabolism and extracellular respiration,and make an in-depth analysis of the molecular biological mechanisms to microbial treatment in wastewater.It is found that electroactive microorganisms are enriched on the material surface,and the expression levels of cytochrome c and riboflavin genes related to electron transfer are up-regulated,confirming that the surface micro-electric field structure could enhance the electron transfer between microbial species and improve the efficiency ofwastewater degradation.This study provides a new idea for the treatment of refractory organic wastewater.展开更多
Wastewater electrolysis cells(WECs)for decentralized wastewater treatment/reuse coupled with H_(2) production can reduce the carbon footprint associated with transportation of water,waste,and energy carrier.This study...Wastewater electrolysis cells(WECs)for decentralized wastewater treatment/reuse coupled with H_(2) production can reduce the carbon footprint associated with transportation of water,waste,and energy carrier.This study reports Ir-doped NiFe_(2)O_(4)(NFI,~5 at%Ir)spinel layer with TiO_(2) overlayer(NFI/TiO_(2)),as a scalable heterojunction anode for direct electrolysis of wastewater with circumneutral pH in a single-compartment cell.In dilute(0.1 M)NaCl solutions,the NFI/TiO_(2) marks superior activity and selectivity for chlorine evolution reaction,outperforming the benchmark IrO_(2).Robust operation in near-neutral pH was confirmed.Electroanalyses including operando X-ray absorption spectroscopy unveiled crucial roles of TiO_(2) which serves both as the primary site for Cl−chemisorption and a protective layer for NFI as an ohmic contact.Galvanostatic electrolysis of NH4+-laden synthetic wastewater demonstrated that NFI/TiO_(2)not only achieves quasi-stoichiometric NH_(4)^(+)-to-N_(2)conversion,but also enhances H_(2)generation efficiency with minimal competing reactions such as reduction of dissolved oxygen and reactive chlorine.The scaled-up WEC with NFI/TiO_(2)was demonstrated for electrolysis of toilet wastewater.展开更多
The rapidly growing demand for lithium iron phosphate(LiFePO_(4))as the cathode material of lithium-ion batteries(LIBs)has aggravated the scarcity of phosphorus(P)reserves on Earth.This study introduces an environment...The rapidly growing demand for lithium iron phosphate(LiFePO_(4))as the cathode material of lithium-ion batteries(LIBs)has aggravated the scarcity of phosphorus(P)reserves on Earth.This study introduces an environmentally friendly and economical method of P recovery from municipal wastewater,providing the P source for LiFePO_(4) cathodes.The novel approach utilizes the sludge of Fe-coagulant-based chemical P removal(CPR)in wastewater treatment.After a sintering treatment with acid washing,the CPR sludge,enriched with P and Fe,transforms into purified P-Fe oxides(Fe2.1P1.0O5.6).These oxides can substitute up to 35%of the FePO_(4) reagent as precursor,producing a carbon-coated LiFePO_(4)(LiFePO_(4)/C)cathode with a specific discharge capacity of 114.9 mA·h·g^(-1)at current density of 17 mA·g^(-1)),and cycle stability of 99.2%after 100 cycles.The enhanced cycle performance of the as-prepared LiFePO_(4)/C cathode may be attributed to the incorporations of impurities(such as Ca^(2+)and Na^(+))from sludge,with improved stability of crystal structure.Unlike conventional P-fertilizers,this P recovery technology converts 100%of P in CPR sludge into the production of value-added LiFePO_(4)/C cathodes.The recovered P from municipal wastewater can meet up to 35%of the P demand in the Chinese LIBs industry,offering a cost-effective solution for addressing the pressing challenges of P scarcity.展开更多
In this study,the effects of different salinity gradients and addition of compatible solutes on anaerobic treated effluent water qualities,sludge characteristics and microbial communities were investigated.The increas...In this study,the effects of different salinity gradients and addition of compatible solutes on anaerobic treated effluent water qualities,sludge characteristics and microbial communities were investigated.The increase in salinity resulted in a decrease in particle size of the granular sludge,which was concentrated in the range of 0.5-1.0 mm.The content of EPS(extracellular polymeric substances)in the granular sludge gradually increased with increasing salinity and the addition of betaine(a typical compatible solute).Meanwhile,the microbial community structure was significantly affected by salinity,with high salinity reducing the diversity of bacteria.At higher salinity,Patescibacteria and Proteobacteria gradually became the dominant phylum,with relative abundance increasing to 13.53%and 12.16%at 20 g/L salinity.Desulfobacterota and its subordinate Desulfovibrio,which secrete EPS in large quantities,dominated significantly after betaine addition.Their relative abundance reached 13.65%and 7.86%at phylum level and genus level.The effect of these changes on the treated effluent was shown as the average chemical oxygen demand(COD)removal rate decreased from 82.10%to 79.71%,78.01%,68.51%and 64.55%when the salinity gradually increased from 2 g/L to 6,10,16 and 20 g/L.At the salinity of 20 g/L,average COD removal increased to 71.65%by the addition of 2 mmol/L betaine.The gradient elevated salinity and the exogenous addition of betaine played an important role in achieving stability of the anaerobic system in a highly saline environment,which provided a feasible strategy for anaerobic treatment of organic saline wastewater.展开更多
Staphylococcus aureus (S. aureus) is a bacterial pathogen for humans and animals. These bacteria can resist against many antibiotics and this resistance constitute an alarming worldwide human health threat due to the ...Staphylococcus aureus (S. aureus) is a bacterial pathogen for humans and animals. These bacteria can resist against many antibiotics and this resistance constitute an alarming worldwide human health threat due to the morbidity and mortality. Phage therapy is one of the alternative treatments. The aim of this study was to isolate and characterize lytic phages of S. aureus from different wastewater sources in Bobo-Dioulasso, Burkina Faso. Eight strains of S. aureus were isolated from different clinical samples and were used to isolate phages. The isolation and host range of phages were done by the spot test. Phages were purified by the double-layer method. Similar phages after the determination of the host range were characterized using restriction enzymes. A total of 27 phages were obtained after isolation and purification. Nine of the 27 isolates reported a broad host range (≥67%). The results of enzymatic digestion allowed to consider that all phage isolates that presented the same host range and the same genetic fingerprint are the same phage strain;whereas phages that presented the same host range and different genetic fingerprints are different phage strains. Thus, a total of 15 distinct phages isolates specific to S. aureus were characterized. This study highlighted the abundance and lytic capacity of phages isolated from wastewater from Bobo-Dioulasso’s environment against clinical strains of S. aureus. The lytic capacity of these Staphyphages could be an effective alternative tool to combat bacteria multi-resistance.展开更多
Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth...Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth operation of the process, as hydrodynamic constraints require a coarse particle size, whereas wastewater treatment recommends a fine particle size. This study investigates the suitability of laterite and shale as substrates of different sizes (1 - 3, 3 - 5 and 5 - 8 mm) in CWs for domestic wastewater treatment. The study was carried out in an experimental pilot plant consisting of 12 parallelepiped beds (C × C = 0.4 × 0.4 m2;H = 0.6 m) filled from bottom to top with 0.1 m of gravel and 0.4 m of shale or laterite of different grain sizes with two replications. During the six months of operation, plant biomass and stem diameter of Pennisetum purpureum used as vegetation in the CWs were determined. Raw and treated water were also sampled and analyzed for pollutants, including chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total Kjedahl nitrogen (TKN), total phosphorus (TP), and total suspended solids (TSS), using International Organization for Standardization (ISO) analytical methods. P. purpureum developed much better in the CW beds lined with shale;plant biomass ranged from 13.8 to 14.7 kg/m2 and from 11.2 to 12.5 kg/m2 in the beds lined with shale and laterite, respectively, as did stump diameter, which ranged from 15.5 to 16.1 cm and from 11.10 to 12.7 cm, respectively. However, the highest values for biomass and stump diameter for each material were obtained in the beds lined with 1 - 3 mm geomaterials. Pollutant removal efficiencies were highest in the CWs lined with laterite and shale of 1 - 3 mm grain size (76.9% - 83% COD, 78% - 84.7% BOD5, 55.5% - 72.2% TKN, 58.4% - 72.4% TP, 78.1% - 80.2% TSS), with the highest values recorded in the shale-lined beds. However, the 3 - 5 mm grain size of both materials provided quality filtrates (140 - 174 mg/L COD, 78.5 - 94.8 mg/L BOD5, 4.6 - 5.7 mg/L TP) in line with local wastewater discharge levels. This size of geomaterials appears to be suitable for optimization purposes, although further work with these materials, such as increasing the depth of the wetland, is required to improve the level of NTK and TSS discharge.展开更多
Boron-doped diamond(BDD)is a well-known anode material with a high pollutant degradation ability for electrochemical oxidation wastewater treatment.Nevertheless,the cost of production and mechanical strength of BDD me...Boron-doped diamond(BDD)is a well-known anode material with a high pollutant degradation ability for electrochemical oxidation wastewater treatment.Nevertheless,the cost of production and mechanical strength of BDD membranes remain unsatisfactory.Magnetic BDD particles derived from industrial waste may represent a promising alternative to BDD membranes,although the challenge remains in assembling these particles into a usable electrode.In this study,magnetic BDD particles were attracted to a Ti/RuO_(2)-IrO_(2)electrode using a magnet,thus constituting a novel 2.5-dimensional(2.5D)electrode.To ascertain the structure-activity relationship of the novel electrode,essential characterizations,multi-physics simulations,pollutant degradation and electrosynthesis experiments were conducted.The results indicate that an appropriate quantity of BDD particles(0.1 g/cm^(2))can enhance the number of active sites by approximately 20%.A strong synergistic effect was observed between the Ti/Ti/RuO_(2)-IrO_(2)and BDD particles in the degradation of various pollutants,including azo dye,p-benzoquinone,succinic acid and four kinds of real wastewaters,as well as glycerol conversion.The joint active sites on the interface between Ti/RuO_(2)-IrO_(2)and BDD particles,as well as the inner active sites on BDD particles,have been identified as crucial in the mineralization of pollutants and the generation of value-added products.The optimal amount of BDD particles(0.1 g/cm^(2))is sufficient to preserve the joint active sites and to maintain an adequate polarization on the BDD particles.Nevertheless,the hybrid feature of the 2.5D electrode is diminished when a greater quantity of BDD particles(0.3 g/cm^(2))is loaded.展开更多
Under conditions of increased pollution of water resources,the search for effective and environmentally safe methods of wastewater treatment becomes an urgent task.As noted by many researchers Lemna minor L.and Azolla...Under conditions of increased pollution of water resources,the search for effective and environmentally safe methods of wastewater treatment becomes an urgent task.As noted by many researchers Lemna minor L.and Azolla caroliniana have great potential for biological treatment of wastewater.The present study is devoted to the biological treatment of municipal wastewater of Osh city(Kyrgyzstan)using aquatic plants Lemna minor L.and Azolla caroliniana Willd.Experiments were conducted in concrete basins of treatment facilities.The area of each pool was 1 m^(2),depth 30–45 cm.The temperature of nutrient media ranged from 20 to 35℃,pH from 6.1 to 8.7,and light intensity from 284 to 360 W/m^(2)FAR.The results showed that the cultivation of Lemna minor resulted in the oxygenation of wastewater and,a significant reduction of pollutants and pathogens.At the same time,the use of Azolla caroliniana provided a significant improvement in the physicochemical characteristics of water-reduction of BOD_(5)to 4.3 mgO_(2)/L,disappearance of all forms of nitrogen,as well as improvement of transparency and elimination of unpleasant odor.Thus,both plants showed high potential as biological treatment agents.The obtained data confirm the prospect of their application for a sustainable water treatment system in the conditions of southern regions of Kyrgyzstan.展开更多
Wastewater plays a crucial role in deteriorating water quality and can significantly affect human health and ecosystems if discharged without proper treatment.Among available treatment methods,adsorption is often cons...Wastewater plays a crucial role in deteriorating water quality and can significantly affect human health and ecosystems if discharged without proper treatment.Among available treatment methods,adsorption is often considered an effective,relatively inexpensive,and environmentally friendly purification technique,but its efficiency depends on the sorbents used.The use of low-cost biosorbents with high adsorption capacity is widely studied.These include various biomaterials such as microalgae,cyanobacteria,fungi,and plant materials.The utilization of different biosorbents derived from plant waste,such as Paulownia wood,aspen,hickory,Ziziphus bark,peach tree shavings,as well as grasses such as red fescue and reed,and Sargassum algae in natural and modified forms,is a crucial research direction.Such studies highlight the potential to address waste issues by repurposing it as biosorbents.Several studies have examined the ability of different biosorbents to treat wastewater and suggested that the physicochemical properties of the material's surface,such as specific surface area,pore size,and pore volume,play a decisive role in adsorption capacity.A quantitative analysis of plant-based biosorbents will significantly aid in developing water treatment systems and achieving optimal adsorption through modifications of their physicochemical properties.Furthermore,the analysis will help understand the relative importance of each physicochemical property in determining adsorption capacity,thereby contributing to the implementation of treatment methods targeting specific pollutants.展开更多
Copper-zinc-nickel(Cu-Zn-Ni)ferrite nanoparticles are used for wastewater treatment technology.However,low degradation efficiency and stability are two main issues that make them unsuitable for actual production needs...Copper-zinc-nickel(Cu-Zn-Ni)ferrite nanoparticles are used for wastewater treatment technology.However,low degradation efficiency and stability are two main issues that make them unsuitable for actual production needs.In this paper,the citrate-nitrate auto-combustion method was applied for the formation of Cu_(0.5)Zn_(0.25)Ni_(0.25)La_(x)Fe_(2-x)O_(4);(0≤x≤0.1;step 0.02)(CZNL)nanoferrites.Although the substitution process entails the replacement of a small ion with a larger one,the lattice constant and crystallite size does not exhibit a consistent incremental pattern.This behavior is justified and discussed.The size of all the CZNL ferrite nanoparticles is in the range of 8-12 nm,and the lattice constant is in the range of 8.6230 to 8.4865 nm.The morphological analysis conducted using field emission-scanning electron microscopy(FE-SEM)reveals that the CZNL exhibits agglomerated spherical morphology.The energy dispersive X-ray spectrameter(EDAX)analysis was employed to confirm the elemental composition of CZNL nanoferrites.Since the process entails the substitution of Fe^(3+)magnetic ions with nonmagnetic ions La^(3+),the magnetic parameters of CZNL nanoferrites show a general decreasing trend as predicted.At 20 K,saturation magnetization Ms shows an overall drop in its values from 59.302 emu/g at x=0.0-41.295 emu/g at x=0.1,the smallest value of 37.87 emu/g is recorded at x=0.06.the highest coercivity(H_(c)=125.9 Oe)and remanence(M_(r)=13.32 emu/g)are recorded for x=0.08 and x=0.04 nanoferrite,respectvely.The band gap of all the CZNL nanoferrites was determined using the Kubelka-Munk function and Tauc plot for direct permitted transitions.La doping modifies the band gap(within 1.86-1.75 eV),increases light absorption,induces efficient e/h separation and charge migration to Cu_(0.5)Zn_(0.25)Ni_(0.25)La_(x)Fe_(2-x)O_(4)surfaces.The nanoferrite Cu_(0.5)Zn_(0.25)Ni_(0.25)La_(0.06)Fe_(1.94)O_(4)achieves a degradation efficiency of 97.3%for methylene blue(MB)dye removal after just 60 min.After five recycling processes,the nanocatalyst Cu_(0.5)Zn_(0.25)Ni_(0.25)La_(0.06)Fe_(1.94)O_(4)is degraded by 95.83%,resulting in a negligible1.51%decrease in photocatalytic activity efficiency.The new Cu_(0.5)Zn_(0.25)Ni_(0.25)La_(0.06)Fe_(1.94)O_(4)has exceptional photocatalytic activity and remarkable stability,making it a promising candidate for applications in wastewater treatment.展开更多
Aiming to solve the problem of large discharge and severe pollution of reactive dyeing wastewater for wool fabrics,peroxodisulfate(SPS)was used for the degradation and recycling of dyeing wastewater containing reactiv...Aiming to solve the problem of large discharge and severe pollution of reactive dyeing wastewater for wool fabrics,peroxodisulfate(SPS)was used for the degradation and recycling of dyeing wastewater containing reactive dye Lanasol Red CE.The process of degrading the reactive dye was determined by using the dye residual rate as the evaluation index.The feasibility of reactive dyeing of wool fabrics using recycled dyeing wastewater was confirmed by measuring the dye uptake,exhaustion and fixation rates,as well as color parameters and fastness of the dyed fabrics.The results showed that the appropriate conditions for degrading Lanasol Red CE were 0.2 g/L SPS,an initial pH value of 3 and 100℃for 30 min.Under these conditions,the dye degradation rate was as high as 93.14%.When the recycled dyeing wastewater was used for dyeing of wool fabrics,the exhaustion rate of Lanasol Red CE exceeded 99%,and the fixation rate was higher than that achieved by the conventional dyeing process.Under the same dyeing conditions,the recycled-dyed fabrics appeared darker.When the number of cycles was fewer than five,the effect on color fastness was not obvious.Although the color fastness to rubbing and washing of the fabrics dyed in the 10th cycle decreased by half a grade and 1 grade,respectively,compared to that of the fabrics dyed with the conventional dyeing process,they still met the production requirements.展开更多
Coking wastewater,characterized by high biological toxicity,poses significant challenges for traditional biological treatment methods.This study developed a novel in-situ immobilized photocatalytic-algae-bacteria cons...Coking wastewater,characterized by high biological toxicity,poses significant challenges for traditional biological treatment methods.This study developed a novel in-situ immobilized photocatalytic-algae-bacteria consortia(P-ABC)system using a polyether polyurethane sponge as a carrier,aiming to enhance biological treatment efficiency for actual coking wastewater.Results showed a 16.8%increase in algal density(up to 1.51×10^(5) cells/mL)in the P-ABC system compared to non-coupled controls,with significantly improved microbial metabolic activity,confirming the carrier's exceptional biocompatibility.Compared to standalone algae-bacteria consortia systems,the P-ABC system achieved higher removal efficiencies for chemical oxygen demand(COD_(Cr),19.8%),total organic carbon(TOC,21.2%),and total nitrogen(TN,30.4%).These findings validate the system's potential for improving stable and efficient treatment of industrial wastewater.Furthermore,this study offers insights into bio-enhanced treatment technologies and provides a reference pathway for integrating advanced oxidation and biological processes.展开更多
Industrial activities have contributed so much to the pollution of water bodies and these pollutions have adversely affected the aquatic ecosystem.This study aimed to investigate the ecological risk evaluation of heav...Industrial activities have contributed so much to the pollution of water bodies and these pollutions have adversely affected the aquatic ecosystem.This study aimed to investigate the ecological risk evaluation of heavy metal accumulation in Aba River bottom sediments:implications for soap and detergent industry wastewater management.Varian AA240 Atomic absorption spectrometer was used to analyse heavy metals.Individual and complex ecological indices were used to evaluate heavy metal contamination in bottom sediments.According to the results,the heavy metal properties of the wastewater indicated that Fe,Pb,Cd,Cr and Cu mean concentration values were higher than the World Health Organization(WHO)and the National Environmental Standards and Regulations Enforcement Agency(NESREA)permissible limits.Heavy metal properties of the surface water in Aba River(dry seasons)showed that Pb,Cd,Cu,Mn,Fe,and Cr,mean concentrations were above the NESREA,WHO and U.S.Environmental Protection Agency(USEPA)permissible limits.Heavy metal properties of the bottom sediments of Aba River(wet and dry season)showed that Pb,Cd,and Fe mean concentrations were significantly higher than the NESREA,WHO and USEPA permissible limits.The heavy metal contamination factor(CF)of sediments obtained from Aba River during the wet and dry season was low and the CFs of each of the assayed heavy metals were less than 1(CD<1).This also signifies the existence of a low contamination in the sediments of the course streams of Aba River during wet and dry season.The pollution load index(PLI)values of Aba River(sediment)indicated that there is no metal pollution at PLI<1 in the sampled sediments.The potential ecological risk index(RI)of Aba River was less than 150(RI<150)indicating a low ecological RI.Abatement of pollutants in the wastewater to permissible concentrations required for natural environment protection is needed.展开更多
The global concern surrounding the advancement of methods for treating wastewater and polluted soil has markedly increased over time.While electrochemical advanced oxidation processes(EAOPs)and biotreatments are commo...The global concern surrounding the advancement of methods for treating wastewater and polluted soil has markedly increased over time.While electrochemical advanced oxidation processes(EAOPs)and biotreatments are commonly employed technologies for remediating wastewater and polluted soil,their widespread adoption is hindered by their limitations,which include high costs associated with EAOPs and prolonged remediation time of biotreatments.In the review,we provided an overviewof EAOP technology and biotreatment,emphasizing the critical aspects involved in building a combined system.This review systematically evaluates recent research that combines EAOPswith bioremediation for treating wastewater or contaminated soil as pretreatment or post-treatment process.Research findings suggest that the combined treatment method represents a promising and competitive technology that can overcome some of the limitations of individual treatments.Additionally,we discussed the potential applications of this technology in varying levels of wastewater and soil pollution,as well as the underlying combination mechanisms.展开更多
Treating municipal wastewater is essential to safeguarding both ecosystem integrity and public health.Although wastewater treatment plants(WWTPs)significantly improve effluent quality,they also incur collateral enviro...Treating municipal wastewater is essential to safeguarding both ecosystem integrity and public health.Although wastewater treatment plants(WWTPs)significantly improve effluent quality,they also incur collateral environmental burdens.In this investigation,a"gate-to-gate"Life Cycle Assessment(LCA)was conducted to analyze the environmental performance of two major WWTPs in Arequipa:La Escalerilla(Plant A,activated sludge)and La Enlozada(Plant B,trickling filters).The analysis was conducted using OpenLCA and the ReCiPe Midpoint(H)2016 impact assessment method,with a functional unit defined as 1 m^(3)of treated effluent.Energy consumption emerges as the primary driver for the climate change(GWP100),fossil depletion(FDP),and human toxicity(HTPinf)impact categories,accounting for approximately 75% to 85% of the total effects.Plant A,which requires 0.59 kWh/m^(3)of electricity,achieves superior nutrient removal reflected in a freshwater eutrophication potential of 1.92×10^(-6) kg P-eq/m^(3),and exhibits marginally higher CO_(2)-eq emissions(GWP100)(1.17×10^(-1) kg CO_(2)-eq/m^(3)).Conversely,Plant B consumes only 0.34 kWh/m^(3),resulting in a slightly lower GWP100(1.14×10^(-1) kg CO_(2)-eq/m^(3))and a significantly greater reduction in fossil depletion potential(FDP)(2.56×10^(-2) kg oil-eq/m^(3)vs.Plant A's 4.75×10^(-2) kg oil-eq/m^(3)),although it exhibits an elevated eutrophication potential of 4.10×10^(-6) kg P-eq/m^(3).Both plants meet discharge standards.This study shows that treatment technologies must balance efficiency and sustainability,with energy use being critical.As Peruvian LCA research is scarce,these results offer key insights for future policies.展开更多
Nitrate(NO3-)is a widespread pollutant in high-salt wastewater and causes serious harm to human health.Although electrochemical removal of nitrate has been demonstrated to be a promising treatment method,the developme...Nitrate(NO3-)is a widespread pollutant in high-salt wastewater and causes serious harm to human health.Although electrochemical removal of nitrate has been demonstrated to be a promising treatment method,the development of low-cost electro-catalysts is still challenging.In this work,a phosphate modified iron(P-Fe)cathode was prepared for electrochemical removal of nitrate in high-salt wastewater.The phosphate modification greatly improved the activity of iron,and the removal rate of nitrate on P-Fe was three times higher than that on Fe electrode.Further experiments and density functional theory(DFT)calculations demonstrated that the modification of phosphoric acid improved the stability and the activity of the zero-valent iron electrode effectively for NO_(3)^(-) removal.The nitrate was firstly electrochemically reduced to ammonium,and then reacted with the anodic generated hypochlorite to N_(2).In this study,a strategy was developed to improve the activity and stability of metal electrode for NO_(3)^(-)removal,which opened up a new field for the efficient reduction of NO3-removal by metal electrode materials.展开更多
Dairy wastewater,a kind of high concentration organic wastewater,is produced in large quantities and difficult to treat,and has a negative impact on the ecological environment.In this study,the source,composition,wate...Dairy wastewater,a kind of high concentration organic wastewater,is produced in large quantities and difficult to treat,and has a negative impact on the ecological environment.In this study,the source,composition,water quality characteristics of dairy wastewater and its impact on the ecological environment were analyzed,and the treatment methods of dairy wastewater at home and abroad in recent years were summarized,in order to provide a reference for the treatment of dairy wastewater.展开更多
Electrocatalytic urea wastewater treatment technology has emerged as a promising method for environmental remediation.However,the realization of highly efficient and scalable electrocatalytic urea wastewater treatment...Electrocatalytic urea wastewater treatment technology has emerged as a promising method for environmental remediation.However,the realization of highly efficient and scalable electrocatalytic urea wastewater treatment(SEUWT)is still an enormous challenge.Herein,through regulating the adsorption behavior of urea functional groups,the efficient SEUWT coupled hydrogen production is realized in anion exchange membrane water electrolyzer(AEMWE).Density functional theory calculations indicate that self-driven electron transfer at the heterogeneous interface(NiO/Co_(3)O_(4))can induce charge redistribution,resulting in electron-rich NiO and electron-deficient Co_(3)O_(4),which are superior to adsorbing C=O(electron-withdrawing group)and–NH_(2)(electron-donating group),respectively,regulating the adsorption behavior of urea molecule and accelerating the reaction kinetics of urea oxidation.This viewpoint is further verified by temperature-programmed desorption experiments.The SEUWT coupled hydrogen production in AEMWE assembled with NiO/Co_(3)O_(4)(anode)and NiCoP(cathode)can continuously treat urea wastewater at an initial current density of 600 mA cm^(-2),with the average urea treatment efficiency about 53%.Compared with overall water splitting,the H_(2) production rate(8.33 mmol s^(-1))increases by approximately 3.5 times.This work provides a cost-effective strategy for scalable purifying urea-rich wastewater and energy-saving hydrogen production.展开更多
基金Project supported by the National Natural Science Foundation of China(52104354)the National Natural Science Foundation of China(51674036)+1 种基金Joint Fund for Nuclear Technology Innovation Sponsored by the National Natural Science Foundation of Chinathe China National Nuclear Corporation(U2067201)。
文摘Comprehensive utilization of phosphogypsum(PG)has attracted much attention,especially for the recovery of rare earth elements(REEs)and gypsum due to the issues of stockpile,environmental pollution,and waste of associated resources.Traditional utilization methods suffered the issues of low REEs leaching efficiency,huge amount of CaSO_(4)saturated wastewater and high recovery cost.To solve these issues,this study investigated the occurrence of REEs in PG and the leaching of REEs.The results show that REEs in PG are in the forms of(1)REEs mineral inclusions,(2)REEs isomorphous substitution of Ca^(2+)in gypsum lattice,(3)dispersed soluble REEs salts.Acid leaching results demonstrate that(1)the dissolution of gypsum matrix is the control factor of REEs leaching;(2)H_(2)SO_(4)is a promising leachant considering the recycle of leachate;(3)the gypsum matrix suffers a recrystallization during the acid leaching and releases the soluble REEs from PG to aqueous solution.For the recovery of the undissolved REEs mineral inclusions,wet sieving concentrated 37.1 wt%of the REEs in a 10.7 wt%mass,increasing REEs content from 309 to 1071 ppm.Finally,a green process combining gravity separation and hydrometallurgy is proposed.This process owns the merits of wastewater free,considerable REEs recovery(about 10%increase compared with traditional processes),excellent gypsum purification(>95 wt%CaSO_(4)·2H_(2)O,with<0.06 wt%of soluble P_(2)O_(5) and<0.015 wt%of soluble F)and reagent saving(about 2/3less reagent consumption than non-cyclical leaching).
基金supported by the Science and Technology Planning Project of Fujian Province(No.2023Y4015)the Marine and Fishery Development Special Fund of Xiamen(No.23YYST064QCB36)the Natural Science Foundation of Fujian Province(No.2021J011210).
文摘The removal of ammonia nitrogen(NH_(4)^(+)-N)and bacteria from aquaculture wastewater holds paramount ecological and production significance.In this study,Pt/RuO_(2)/g-C_(3)N_(4)photocatalysts were prepared by depositing Pt and RuO_(2)particles onto g-C_(3)N_(4).The physicochemical properties of photocatalysts were explored by X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),X-ray diffraction(XRD),and UV–vis diffuse reflectance spectrometer(UV–vis DRS).The photocatalysts were then applied to the removal of both NH_(4)^(+)-N and bacteria from simulated mariculture wastewater.The results clarified that the removals of both NH_(4)^(+)-N and bacteria were in the sequence of g-C_(3)N_(4)<RuO_(2)/g-C_(3)N_(4)<Pt/g-C_(3)N_(4)<Pt/RuO_(2)/g-C_(3)N_(4).This magnificent photocatalytic ability of Pt/RuO_(2)/g-C_(3)N_(4)can be interpreted by the transfer of holes from g-C_(3)N_(4)to RuO_(2)to facilitate the in situ generation of HClO from Cl^(−)in wastewater,while Pt extracts photogenerated electrons for H_(2)formation to enhance the reaction.The removal of NH_(4)^(+)-N and disinfection effect were more pronounced in simulated seawater than in purewater.The removal efficiency ofNH_(4)^(+)-N increases with an increase in pH of wastewater,while the bactericidal effect was more significant under a lower pH in a pH range of 6–9.In actual seawater aquaculture wastewater,Pt/RuO_(2)/g-C_(3)N_(4)still exhibits effective removal efficiency of NH_(4)^(+)-N and bactericidal performance under sunlight.This study provides an alternative avenue for removement of NH_(4)^(+)-N and bacteria from saline waters under sunlight.
基金supported by the National Natural Science Foundation of China(Nos.52150056 and 51838005)the Basic and Applied Basic Research Foundation of Guangdong Province(No.2023A1515111061).
文摘The kitchen-oil wastewater is characterized by a high concentration of organicmatter,complex composition and refractory pollutants,which make wastewater treatment more difficult.Based on the study of using micro-electric field characteristic catalyst HCLL-S8-M to enhance the electron transfer between microorganisms in kitchen-oil wastewater which further improved the COD removal rate,we focus on themicrobial community,intracellular metabolism and extracellular respiration,and make an in-depth analysis of the molecular biological mechanisms to microbial treatment in wastewater.It is found that electroactive microorganisms are enriched on the material surface,and the expression levels of cytochrome c and riboflavin genes related to electron transfer are up-regulated,confirming that the surface micro-electric field structure could enhance the electron transfer between microbial species and improve the efficiency ofwastewater degradation.This study provides a new idea for the treatment of refractory organic wastewater.
基金supported by the National Research Foundation of Korea(NRF)grants(2022R1A2C4001228,2022M3H4A4097524,2022M3I3A1082499,and 2021M3I3A1084818)the Technology Innovation Program(20026415)of the Ministry of Trade,Industry&Energy(MOTIE,Korea)the supports from Nanopac for fabrication of scaled-up reactor.
文摘Wastewater electrolysis cells(WECs)for decentralized wastewater treatment/reuse coupled with H_(2) production can reduce the carbon footprint associated with transportation of water,waste,and energy carrier.This study reports Ir-doped NiFe_(2)O_(4)(NFI,~5 at%Ir)spinel layer with TiO_(2) overlayer(NFI/TiO_(2)),as a scalable heterojunction anode for direct electrolysis of wastewater with circumneutral pH in a single-compartment cell.In dilute(0.1 M)NaCl solutions,the NFI/TiO_(2) marks superior activity and selectivity for chlorine evolution reaction,outperforming the benchmark IrO_(2).Robust operation in near-neutral pH was confirmed.Electroanalyses including operando X-ray absorption spectroscopy unveiled crucial roles of TiO_(2) which serves both as the primary site for Cl−chemisorption and a protective layer for NFI as an ohmic contact.Galvanostatic electrolysis of NH4+-laden synthetic wastewater demonstrated that NFI/TiO_(2)not only achieves quasi-stoichiometric NH_(4)^(+)-to-N_(2)conversion,but also enhances H_(2)generation efficiency with minimal competing reactions such as reduction of dissolved oxygen and reactive chlorine.The scaled-up WEC with NFI/TiO_(2)was demonstrated for electrolysis of toilet wastewater.
基金supported by the National Natural Science Foundation of China(52100093,52270128,and 52261135627)the Guangdong Basic and Applied Basic Research Foundation(2023A1515011734 and 2021B1515120068)+2 种基金the Municipal Science and Technology Innovation Council of the Shen-zhen Government(KCXFZ20211020163556020 and SGDX20230116092359002)the Research Grants Council(17210219)the Innovation and Technology Fund(ITS/242/20FP)of the Hong Kong SAR Government。
文摘The rapidly growing demand for lithium iron phosphate(LiFePO_(4))as the cathode material of lithium-ion batteries(LIBs)has aggravated the scarcity of phosphorus(P)reserves on Earth.This study introduces an environmentally friendly and economical method of P recovery from municipal wastewater,providing the P source for LiFePO_(4) cathodes.The novel approach utilizes the sludge of Fe-coagulant-based chemical P removal(CPR)in wastewater treatment.After a sintering treatment with acid washing,the CPR sludge,enriched with P and Fe,transforms into purified P-Fe oxides(Fe2.1P1.0O5.6).These oxides can substitute up to 35%of the FePO_(4) reagent as precursor,producing a carbon-coated LiFePO_(4)(LiFePO_(4)/C)cathode with a specific discharge capacity of 114.9 mA·h·g^(-1)at current density of 17 mA·g^(-1)),and cycle stability of 99.2%after 100 cycles.The enhanced cycle performance of the as-prepared LiFePO_(4)/C cathode may be attributed to the incorporations of impurities(such as Ca^(2+)and Na^(+))from sludge,with improved stability of crystal structure.Unlike conventional P-fertilizers,this P recovery technology converts 100%of P in CPR sludge into the production of value-added LiFePO_(4)/C cathodes.The recovered P from municipal wastewater can meet up to 35%of the P demand in the Chinese LIBs industry,offering a cost-effective solution for addressing the pressing challenges of P scarcity.
基金supported by the Guangdong Special Support ProgramProject(No.2021JC060580)the Foshan Innovation Team Project(No.2130218003140).
文摘In this study,the effects of different salinity gradients and addition of compatible solutes on anaerobic treated effluent water qualities,sludge characteristics and microbial communities were investigated.The increase in salinity resulted in a decrease in particle size of the granular sludge,which was concentrated in the range of 0.5-1.0 mm.The content of EPS(extracellular polymeric substances)in the granular sludge gradually increased with increasing salinity and the addition of betaine(a typical compatible solute).Meanwhile,the microbial community structure was significantly affected by salinity,with high salinity reducing the diversity of bacteria.At higher salinity,Patescibacteria and Proteobacteria gradually became the dominant phylum,with relative abundance increasing to 13.53%and 12.16%at 20 g/L salinity.Desulfobacterota and its subordinate Desulfovibrio,which secrete EPS in large quantities,dominated significantly after betaine addition.Their relative abundance reached 13.65%and 7.86%at phylum level and genus level.The effect of these changes on the treated effluent was shown as the average chemical oxygen demand(COD)removal rate decreased from 82.10%to 79.71%,78.01%,68.51%and 64.55%when the salinity gradually increased from 2 g/L to 6,10,16 and 20 g/L.At the salinity of 20 g/L,average COD removal increased to 71.65%by the addition of 2 mmol/L betaine.The gradient elevated salinity and the exogenous addition of betaine played an important role in achieving stability of the anaerobic system in a highly saline environment,which provided a feasible strategy for anaerobic treatment of organic saline wastewater.
文摘Staphylococcus aureus (S. aureus) is a bacterial pathogen for humans and animals. These bacteria can resist against many antibiotics and this resistance constitute an alarming worldwide human health threat due to the morbidity and mortality. Phage therapy is one of the alternative treatments. The aim of this study was to isolate and characterize lytic phages of S. aureus from different wastewater sources in Bobo-Dioulasso, Burkina Faso. Eight strains of S. aureus were isolated from different clinical samples and were used to isolate phages. The isolation and host range of phages were done by the spot test. Phages were purified by the double-layer method. Similar phages after the determination of the host range were characterized using restriction enzymes. A total of 27 phages were obtained after isolation and purification. Nine of the 27 isolates reported a broad host range (≥67%). The results of enzymatic digestion allowed to consider that all phage isolates that presented the same host range and the same genetic fingerprint are the same phage strain;whereas phages that presented the same host range and different genetic fingerprints are different phage strains. Thus, a total of 15 distinct phages isolates specific to S. aureus were characterized. This study highlighted the abundance and lytic capacity of phages isolated from wastewater from Bobo-Dioulasso’s environment against clinical strains of S. aureus. The lytic capacity of these Staphyphages could be an effective alternative tool to combat bacteria multi-resistance.
文摘Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth operation of the process, as hydrodynamic constraints require a coarse particle size, whereas wastewater treatment recommends a fine particle size. This study investigates the suitability of laterite and shale as substrates of different sizes (1 - 3, 3 - 5 and 5 - 8 mm) in CWs for domestic wastewater treatment. The study was carried out in an experimental pilot plant consisting of 12 parallelepiped beds (C × C = 0.4 × 0.4 m2;H = 0.6 m) filled from bottom to top with 0.1 m of gravel and 0.4 m of shale or laterite of different grain sizes with two replications. During the six months of operation, plant biomass and stem diameter of Pennisetum purpureum used as vegetation in the CWs were determined. Raw and treated water were also sampled and analyzed for pollutants, including chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total Kjedahl nitrogen (TKN), total phosphorus (TP), and total suspended solids (TSS), using International Organization for Standardization (ISO) analytical methods. P. purpureum developed much better in the CW beds lined with shale;plant biomass ranged from 13.8 to 14.7 kg/m2 and from 11.2 to 12.5 kg/m2 in the beds lined with shale and laterite, respectively, as did stump diameter, which ranged from 15.5 to 16.1 cm and from 11.10 to 12.7 cm, respectively. However, the highest values for biomass and stump diameter for each material were obtained in the beds lined with 1 - 3 mm geomaterials. Pollutant removal efficiencies were highest in the CWs lined with laterite and shale of 1 - 3 mm grain size (76.9% - 83% COD, 78% - 84.7% BOD5, 55.5% - 72.2% TKN, 58.4% - 72.4% TP, 78.1% - 80.2% TSS), with the highest values recorded in the shale-lined beds. However, the 3 - 5 mm grain size of both materials provided quality filtrates (140 - 174 mg/L COD, 78.5 - 94.8 mg/L BOD5, 4.6 - 5.7 mg/L TP) in line with local wastewater discharge levels. This size of geomaterials appears to be suitable for optimization purposes, although further work with these materials, such as increasing the depth of the wetland, is required to improve the level of NTK and TSS discharge.
基金the National Natural Science Foundation of China(Nos.21706153,52270078)Natural Science Basic Research Program of Shaanxi Province(Nos.2018JQ2066,2022JM065)。
文摘Boron-doped diamond(BDD)is a well-known anode material with a high pollutant degradation ability for electrochemical oxidation wastewater treatment.Nevertheless,the cost of production and mechanical strength of BDD membranes remain unsatisfactory.Magnetic BDD particles derived from industrial waste may represent a promising alternative to BDD membranes,although the challenge remains in assembling these particles into a usable electrode.In this study,magnetic BDD particles were attracted to a Ti/RuO_(2)-IrO_(2)electrode using a magnet,thus constituting a novel 2.5-dimensional(2.5D)electrode.To ascertain the structure-activity relationship of the novel electrode,essential characterizations,multi-physics simulations,pollutant degradation and electrosynthesis experiments were conducted.The results indicate that an appropriate quantity of BDD particles(0.1 g/cm^(2))can enhance the number of active sites by approximately 20%.A strong synergistic effect was observed between the Ti/Ti/RuO_(2)-IrO_(2)and BDD particles in the degradation of various pollutants,including azo dye,p-benzoquinone,succinic acid and four kinds of real wastewaters,as well as glycerol conversion.The joint active sites on the interface between Ti/RuO_(2)-IrO_(2)and BDD particles,as well as the inner active sites on BDD particles,have been identified as crucial in the mineralization of pollutants and the generation of value-added products.The optimal amount of BDD particles(0.1 g/cm^(2))is sufficient to preserve the joint active sites and to maintain an adequate polarization on the BDD particles.Nevertheless,the hybrid feature of the 2.5D electrode is diminished when a greater quantity of BDD particles(0.3 g/cm^(2))is loaded.
文摘Under conditions of increased pollution of water resources,the search for effective and environmentally safe methods of wastewater treatment becomes an urgent task.As noted by many researchers Lemna minor L.and Azolla caroliniana have great potential for biological treatment of wastewater.The present study is devoted to the biological treatment of municipal wastewater of Osh city(Kyrgyzstan)using aquatic plants Lemna minor L.and Azolla caroliniana Willd.Experiments were conducted in concrete basins of treatment facilities.The area of each pool was 1 m^(2),depth 30–45 cm.The temperature of nutrient media ranged from 20 to 35℃,pH from 6.1 to 8.7,and light intensity from 284 to 360 W/m^(2)FAR.The results showed that the cultivation of Lemna minor resulted in the oxygenation of wastewater and,a significant reduction of pollutants and pathogens.At the same time,the use of Azolla caroliniana provided a significant improvement in the physicochemical characteristics of water-reduction of BOD_(5)to 4.3 mgO_(2)/L,disappearance of all forms of nitrogen,as well as improvement of transparency and elimination of unpleasant odor.Thus,both plants showed high potential as biological treatment agents.The obtained data confirm the prospect of their application for a sustainable water treatment system in the conditions of southern regions of Kyrgyzstan.
文摘Wastewater plays a crucial role in deteriorating water quality and can significantly affect human health and ecosystems if discharged without proper treatment.Among available treatment methods,adsorption is often considered an effective,relatively inexpensive,and environmentally friendly purification technique,but its efficiency depends on the sorbents used.The use of low-cost biosorbents with high adsorption capacity is widely studied.These include various biomaterials such as microalgae,cyanobacteria,fungi,and plant materials.The utilization of different biosorbents derived from plant waste,such as Paulownia wood,aspen,hickory,Ziziphus bark,peach tree shavings,as well as grasses such as red fescue and reed,and Sargassum algae in natural and modified forms,is a crucial research direction.Such studies highlight the potential to address waste issues by repurposing it as biosorbents.Several studies have examined the ability of different biosorbents to treat wastewater and suggested that the physicochemical properties of the material's surface,such as specific surface area,pore size,and pore volume,play a decisive role in adsorption capacity.A quantitative analysis of plant-based biosorbents will significantly aid in developing water treatment systems and achieving optimal adsorption through modifications of their physicochemical properties.Furthermore,the analysis will help understand the relative importance of each physicochemical property in determining adsorption capacity,thereby contributing to the implementation of treatment methods targeting specific pollutants.
文摘Copper-zinc-nickel(Cu-Zn-Ni)ferrite nanoparticles are used for wastewater treatment technology.However,low degradation efficiency and stability are two main issues that make them unsuitable for actual production needs.In this paper,the citrate-nitrate auto-combustion method was applied for the formation of Cu_(0.5)Zn_(0.25)Ni_(0.25)La_(x)Fe_(2-x)O_(4);(0≤x≤0.1;step 0.02)(CZNL)nanoferrites.Although the substitution process entails the replacement of a small ion with a larger one,the lattice constant and crystallite size does not exhibit a consistent incremental pattern.This behavior is justified and discussed.The size of all the CZNL ferrite nanoparticles is in the range of 8-12 nm,and the lattice constant is in the range of 8.6230 to 8.4865 nm.The morphological analysis conducted using field emission-scanning electron microscopy(FE-SEM)reveals that the CZNL exhibits agglomerated spherical morphology.The energy dispersive X-ray spectrameter(EDAX)analysis was employed to confirm the elemental composition of CZNL nanoferrites.Since the process entails the substitution of Fe^(3+)magnetic ions with nonmagnetic ions La^(3+),the magnetic parameters of CZNL nanoferrites show a general decreasing trend as predicted.At 20 K,saturation magnetization Ms shows an overall drop in its values from 59.302 emu/g at x=0.0-41.295 emu/g at x=0.1,the smallest value of 37.87 emu/g is recorded at x=0.06.the highest coercivity(H_(c)=125.9 Oe)and remanence(M_(r)=13.32 emu/g)are recorded for x=0.08 and x=0.04 nanoferrite,respectvely.The band gap of all the CZNL nanoferrites was determined using the Kubelka-Munk function and Tauc plot for direct permitted transitions.La doping modifies the band gap(within 1.86-1.75 eV),increases light absorption,induces efficient e/h separation and charge migration to Cu_(0.5)Zn_(0.25)Ni_(0.25)La_(x)Fe_(2-x)O_(4)surfaces.The nanoferrite Cu_(0.5)Zn_(0.25)Ni_(0.25)La_(0.06)Fe_(1.94)O_(4)achieves a degradation efficiency of 97.3%for methylene blue(MB)dye removal after just 60 min.After five recycling processes,the nanocatalyst Cu_(0.5)Zn_(0.25)Ni_(0.25)La_(0.06)Fe_(1.94)O_(4)is degraded by 95.83%,resulting in a negligible1.51%decrease in photocatalytic activity efficiency.The new Cu_(0.5)Zn_(0.25)Ni_(0.25)La_(0.06)Fe_(1.94)O_(4)has exceptional photocatalytic activity and remarkable stability,making it a promising candidate for applications in wastewater treatment.
基金Youth Foundation of Hebei Province Department of Education Fund,China(No.QN2023090)Opening Project of Textile Ecological Dyeing and Finishing Key Laboratory of Sichuan Province(Chengdu Textile College),China(No.2024DF-AO2)Innovation and Entrepreneurship Training Program for College Students,China(No.202410082023)。
文摘Aiming to solve the problem of large discharge and severe pollution of reactive dyeing wastewater for wool fabrics,peroxodisulfate(SPS)was used for the degradation and recycling of dyeing wastewater containing reactive dye Lanasol Red CE.The process of degrading the reactive dye was determined by using the dye residual rate as the evaluation index.The feasibility of reactive dyeing of wool fabrics using recycled dyeing wastewater was confirmed by measuring the dye uptake,exhaustion and fixation rates,as well as color parameters and fastness of the dyed fabrics.The results showed that the appropriate conditions for degrading Lanasol Red CE were 0.2 g/L SPS,an initial pH value of 3 and 100℃for 30 min.Under these conditions,the dye degradation rate was as high as 93.14%.When the recycled dyeing wastewater was used for dyeing of wool fabrics,the exhaustion rate of Lanasol Red CE exceeded 99%,and the fixation rate was higher than that achieved by the conventional dyeing process.Under the same dyeing conditions,the recycled-dyed fabrics appeared darker.When the number of cycles was fewer than five,the effect on color fastness was not obvious.Although the color fastness to rubbing and washing of the fabrics dyed in the 10th cycle decreased by half a grade and 1 grade,respectively,compared to that of the fabrics dyed with the conventional dyeing process,they still met the production requirements.
基金supported by the National Natural Science Foundation of China(No.22076113)Shaanxi Province Key R&D Program Project(No.2020NY-235)。
文摘Coking wastewater,characterized by high biological toxicity,poses significant challenges for traditional biological treatment methods.This study developed a novel in-situ immobilized photocatalytic-algae-bacteria consortia(P-ABC)system using a polyether polyurethane sponge as a carrier,aiming to enhance biological treatment efficiency for actual coking wastewater.Results showed a 16.8%increase in algal density(up to 1.51×10^(5) cells/mL)in the P-ABC system compared to non-coupled controls,with significantly improved microbial metabolic activity,confirming the carrier's exceptional biocompatibility.Compared to standalone algae-bacteria consortia systems,the P-ABC system achieved higher removal efficiencies for chemical oxygen demand(COD_(Cr),19.8%),total organic carbon(TOC,21.2%),and total nitrogen(TN,30.4%).These findings validate the system's potential for improving stable and efficient treatment of industrial wastewater.Furthermore,this study offers insights into bio-enhanced treatment technologies and provides a reference pathway for integrating advanced oxidation and biological processes.
文摘Industrial activities have contributed so much to the pollution of water bodies and these pollutions have adversely affected the aquatic ecosystem.This study aimed to investigate the ecological risk evaluation of heavy metal accumulation in Aba River bottom sediments:implications for soap and detergent industry wastewater management.Varian AA240 Atomic absorption spectrometer was used to analyse heavy metals.Individual and complex ecological indices were used to evaluate heavy metal contamination in bottom sediments.According to the results,the heavy metal properties of the wastewater indicated that Fe,Pb,Cd,Cr and Cu mean concentration values were higher than the World Health Organization(WHO)and the National Environmental Standards and Regulations Enforcement Agency(NESREA)permissible limits.Heavy metal properties of the surface water in Aba River(dry seasons)showed that Pb,Cd,Cu,Mn,Fe,and Cr,mean concentrations were above the NESREA,WHO and U.S.Environmental Protection Agency(USEPA)permissible limits.Heavy metal properties of the bottom sediments of Aba River(wet and dry season)showed that Pb,Cd,and Fe mean concentrations were significantly higher than the NESREA,WHO and USEPA permissible limits.The heavy metal contamination factor(CF)of sediments obtained from Aba River during the wet and dry season was low and the CFs of each of the assayed heavy metals were less than 1(CD<1).This also signifies the existence of a low contamination in the sediments of the course streams of Aba River during wet and dry season.The pollution load index(PLI)values of Aba River(sediment)indicated that there is no metal pollution at PLI<1 in the sampled sediments.The potential ecological risk index(RI)of Aba River was less than 150(RI<150)indicating a low ecological RI.Abatement of pollutants in the wastewater to permissible concentrations required for natural environment protection is needed.
基金supported by the National Natural Science Foundation of China(No.51709103)the Natural Science Foundation of Hunan Province,China(Nos.2018JJ3242 and 2021JJ30362)the Science and Technology Innovation Leading Plan of High Tech Industry in Hunan Province(No.2021GK4055).
文摘The global concern surrounding the advancement of methods for treating wastewater and polluted soil has markedly increased over time.While electrochemical advanced oxidation processes(EAOPs)and biotreatments are commonly employed technologies for remediating wastewater and polluted soil,their widespread adoption is hindered by their limitations,which include high costs associated with EAOPs and prolonged remediation time of biotreatments.In the review,we provided an overviewof EAOP technology and biotreatment,emphasizing the critical aspects involved in building a combined system.This review systematically evaluates recent research that combines EAOPswith bioremediation for treating wastewater or contaminated soil as pretreatment or post-treatment process.Research findings suggest that the combined treatment method represents a promising and competitive technology that can overcome some of the limitations of individual treatments.Additionally,we discussed the potential applications of this technology in varying levels of wastewater and soil pollution,as well as the underlying combination mechanisms.
基金supported by Universidad Nacional de San Agustin de Arequipa grant number[TP IB-09-2020-UNSA].
文摘Treating municipal wastewater is essential to safeguarding both ecosystem integrity and public health.Although wastewater treatment plants(WWTPs)significantly improve effluent quality,they also incur collateral environmental burdens.In this investigation,a"gate-to-gate"Life Cycle Assessment(LCA)was conducted to analyze the environmental performance of two major WWTPs in Arequipa:La Escalerilla(Plant A,activated sludge)and La Enlozada(Plant B,trickling filters).The analysis was conducted using OpenLCA and the ReCiPe Midpoint(H)2016 impact assessment method,with a functional unit defined as 1 m^(3)of treated effluent.Energy consumption emerges as the primary driver for the climate change(GWP100),fossil depletion(FDP),and human toxicity(HTPinf)impact categories,accounting for approximately 75% to 85% of the total effects.Plant A,which requires 0.59 kWh/m^(3)of electricity,achieves superior nutrient removal reflected in a freshwater eutrophication potential of 1.92×10^(-6) kg P-eq/m^(3),and exhibits marginally higher CO_(2)-eq emissions(GWP100)(1.17×10^(-1) kg CO_(2)-eq/m^(3)).Conversely,Plant B consumes only 0.34 kWh/m^(3),resulting in a slightly lower GWP100(1.14×10^(-1) kg CO_(2)-eq/m^(3))and a significantly greater reduction in fossil depletion potential(FDP)(2.56×10^(-2) kg oil-eq/m^(3)vs.Plant A's 4.75×10^(-2) kg oil-eq/m^(3)),although it exhibits an elevated eutrophication potential of 4.10×10^(-6) kg P-eq/m^(3).Both plants meet discharge standards.This study shows that treatment technologies must balance efficiency and sustainability,with energy use being critical.As Peruvian LCA research is scarce,these results offer key insights for future policies.
基金supported by the National Natural Science Foundation of China (No.22176068)the Research and Innovation Initiatives of WHPU (No.2022J03),the Hubei Provincial Natural Science Foundation (No.2023AFB938)the Scientific research project of Education Department of Hubei Province (No.D20221610).
文摘Nitrate(NO3-)is a widespread pollutant in high-salt wastewater and causes serious harm to human health.Although electrochemical removal of nitrate has been demonstrated to be a promising treatment method,the development of low-cost electro-catalysts is still challenging.In this work,a phosphate modified iron(P-Fe)cathode was prepared for electrochemical removal of nitrate in high-salt wastewater.The phosphate modification greatly improved the activity of iron,and the removal rate of nitrate on P-Fe was three times higher than that on Fe electrode.Further experiments and density functional theory(DFT)calculations demonstrated that the modification of phosphoric acid improved the stability and the activity of the zero-valent iron electrode effectively for NO_(3)^(-) removal.The nitrate was firstly electrochemically reduced to ammonium,and then reacted with the anodic generated hypochlorite to N_(2).In this study,a strategy was developed to improve the activity and stability of metal electrode for NO_(3)^(-)removal,which opened up a new field for the efficient reduction of NO3-removal by metal electrode materials.
文摘Dairy wastewater,a kind of high concentration organic wastewater,is produced in large quantities and difficult to treat,and has a negative impact on the ecological environment.In this study,the source,composition,water quality characteristics of dairy wastewater and its impact on the ecological environment were analyzed,and the treatment methods of dairy wastewater at home and abroad in recent years were summarized,in order to provide a reference for the treatment of dairy wastewater.
基金supported by the National Natural Science Foundation of China(Grant Nos.22162025,22168040)the Youth Innovation Team of Shaanxi Universities,the Open and Innovation Fund of Hubei Three Gorges Laboratory(SK232001)the Regional Innovation Capability Leading Program of Shaanxi(2022QFY07-03,2022QFY07-06).
文摘Electrocatalytic urea wastewater treatment technology has emerged as a promising method for environmental remediation.However,the realization of highly efficient and scalable electrocatalytic urea wastewater treatment(SEUWT)is still an enormous challenge.Herein,through regulating the adsorption behavior of urea functional groups,the efficient SEUWT coupled hydrogen production is realized in anion exchange membrane water electrolyzer(AEMWE).Density functional theory calculations indicate that self-driven electron transfer at the heterogeneous interface(NiO/Co_(3)O_(4))can induce charge redistribution,resulting in electron-rich NiO and electron-deficient Co_(3)O_(4),which are superior to adsorbing C=O(electron-withdrawing group)and–NH_(2)(electron-donating group),respectively,regulating the adsorption behavior of urea molecule and accelerating the reaction kinetics of urea oxidation.This viewpoint is further verified by temperature-programmed desorption experiments.The SEUWT coupled hydrogen production in AEMWE assembled with NiO/Co_(3)O_(4)(anode)and NiCoP(cathode)can continuously treat urea wastewater at an initial current density of 600 mA cm^(-2),with the average urea treatment efficiency about 53%.Compared with overall water splitting,the H_(2) production rate(8.33 mmol s^(-1))increases by approximately 3.5 times.This work provides a cost-effective strategy for scalable purifying urea-rich wastewater and energy-saving hydrogen production.
