In this work,we constructed a three-dimensional electrochemical system(3D-ECO),which included the cathode and anode electrode plates,as well as the screening of three-dimensional particle electrodes and parameter opti...In this work,we constructed a three-dimensional electrochemical system(3D-ECO),which included the cathode and anode electrode plates,as well as the screening of three-dimensional particle electrodes and parameter opti-mization,for the degradation of landfill leachate(LL)containing elevated levels of tetracycline(TC),and explored its mechanism of action.Firstly,titanium-based ruthenium-iridium(Ti/RuO_(2)-IrO_(2)),titanium-based ruthenium-iridium-platinum(Ti/Pt-RuO_(2)-IrO_(2)),and titanium-based tin-antimony(Ti/SnO_(2)-Sb_(2)O_(3))were employed as an-odes in the electrocatalytic oxidation system,with titanium and stainless steel plates serving as cathodes,to construct the optimal two-dimensional electrocatalytic oxidation system(2D-ECO)through cross-comparison ex-periments.Subsequently,using granular activated carbon(GAC),coconut shell biochar(CBC),walnut shell carbon(WBC),and bamboo charcoal(BBC)as particle electrodes,a 3D-ECO system was developed.The influence of var-ious operational parameters on treating TC-containing LL was investigated.The optimal operating parameters obtained from the study was:pH=5,current density of 30 mA/cm^(2),particle dosage of 7 g/L,particle size ranging from 1.70 to 2.00 mm,and electrode spacing of 4 cm.Under these conditions,the COD removal rate of 3D-ECO within three hours was 90.25%,the TC removal rate was 72.41%,and the NH_(3)-N removal rate was 39.52%.The removal of TC followed a pseudo-first-order kinetic model.Additionally,degradation mechanisms were elucidated through electron paramagnetic resonance(EPR)spectrometer and Tert-Butanol(TBA)quenching experiments,indicating that the degradation primarily occurred through a non-radical(1O_(2))pathway.This re-search offers a comprehensive analysis of the simultaneous breakdown of intricate LL matrices and TC,enhancing our comprehension of the degradation processes and underlying mechanisms.展开更多
Enhancing the activity of photocatalysts is a critical challenge for improving the photocatalytic degradation of contaminated wastewater.Here,a novel Ce single-atom-doped titanate nanotube photocatalyst(CeH_(2)Ti_(2)O...Enhancing the activity of photocatalysts is a critical challenge for improving the photocatalytic degradation of contaminated wastewater.Here,a novel Ce single-atom-doped titanate nanotube photocatalyst(CeH_(2)Ti_(2)O_(5)·H_(2)O)was successfully synthesized using a onepot solvothermal method.Degradation experiments revealed that the optimal Ce doping ratio was 1.0%.The ultraviolet-visible diffuse reflectance spectroscopy results showed that the bandgap of the Ce-doped sample decreased from 3.02 to 2.87 eV,enhancing the absorption in the visible spectral range.At the same time,the BrunauerEmmett-Teller specific surface area increased from 63.68 to 88.95 m^(2)g^(-1).The 1.0%Ce-H_(2)Ti_(2)O_(5)·H_(2)O(HTC_(1))could degrade 99.04%of 100 mg L-1rhodamine B(RhB)after 40 min of visible-light irradiation.The degradation efficiency decreased by only 21.24%after five cycles.The results of free-radical quenching and electron spin resonance spectroscopy analyses indicated that HTC_(1)achieved efficient degradation of RhB through a direct hole oxidation mechanism.Compared with pure protonated titanate nanotubes(H_(2)Ti_(2)O_(5)·H_(2)O),HTC_(1)had a higher specific surface area,more electron traps,narrower bandgap,longer hole lifetime,and suppressed photogenerated charge recombination rate owing to the Ce single-atom doping.展开更多
The large molecular weight and high hydrophilicity of chloramphenicol(CAP) residuals in wastewater led to severe degradation difficulty,which propelled the development of new wastewater degradation processes and react...The large molecular weight and high hydrophilicity of chloramphenicol(CAP) residuals in wastewater led to severe degradation difficulty,which propelled the development of new wastewater degradation processes and reactors based on process intensification.This study enhanced the CAP degradation by ozone/peroxydisulfate(PDS) advanced oxidation process in a submerged rotating packed bed(SRPB)reactor.Compared the usage of different oxidants,it was indicated that the combination of O_(3) and PDS exhibited a higher degradation efficiency than ozone and PDS alone.The more desired degradation efficiency could be achieved at the operating conditions of ascending PDS concentration,SRPB rotational speed,ozone concentration,reduced initial CAP concentration,and the water qualities of ascended pH,lower Cl^(-)and initial CO_(3)^(2-) concentrations.Under the optimized conditions of C_(CAP)=20 mg·L^(-1),C_(O3)=30 mg·L^(-1),C_(PDS)=100 mg·L^(-1),and N=400 r·min^(-1),and water qualities of pH=10,the maximum chloramphenicol degradation efficiency of 97% and kinetic constant of 0.23 min^(-1) were achieved after treating 16 min.A comparison of the results with previously reported advanced oxidation processes of CAP indicated that the enhanced O^(3)/PDS advanced oxidation system using the SRPB can significantly improve the degradation efficiency of CAP.展开更多
Addressing the growing challenge of water contamination,this study comparatively evaluated a persulfate(PDS)system activated by nonradical nitrogen-doped carbon nanotubes(N-CNTs)versus a PDS system activated by radica...Addressing the growing challenge of water contamination,this study comparatively evaluated a persulfate(PDS)system activated by nonradical nitrogen-doped carbon nanotubes(N-CNTs)versus a PDS system activated by radical-based iron(Fe^(2+)),both used for the degradation of bisphenol A(BPA).The N-CNTs/PDS system,driven by the electron transfer mechanism,achieved remarkable 90.9%BPA removal within 30 min at high BPA concentrations,significantly outperforming the Fe^(2+)/PDS system,which attained only 38.9%removal.The N-CNTs/PDS system maintained robust degradation efficiency across a wide range of BPA concentrations and exhibited a high degree of resilience in diverse water matrices.By directly abstracting electrons from BPA molecules,the N-CNTs/PDS system effectively minimised oxidant wastage and mitigated the risk of secondary pollution,ensuring efficient utilisation of active sites on N-CNTs and sustaining a high catalytic rate.The formation of the N-CNTs-PDS^(*)complex significantly enhanced BPA degradation and mineralisation,thereby optimising PDS consumption.These findings highlight the unparalleled advantages of the N-CNTs/PDS system in managing complex wastewater,offering a promising and innovative solution for treating complex industrial wastewater and advancing environmental remediation efforts.展开更多
Currently,ferrate(VI)oxidation technology(FOT)has been regarded as one of the most promising options for the degradation of emerging organic pollutants.However,the role and transformation of chloride ions(Cl^(−))in FO...Currently,ferrate(VI)oxidation technology(FOT)has been regarded as one of the most promising options for the degradation of emerging organic pollutants.However,the role and transformation of chloride ions(Cl^(−))in FOT have not been well explored.The current study aims to investigate the formation of chlorinated phenolic byproducts upon ferrate(VI)oxidation processes.The obtained results indicate that chlorides suffering ferrate(VI)attack will be transformed to active chlorine species(ACS),which will subsequently lead to the formation of highly toxic aromatic chlorinated byproducts.The identified byproducts include common chlorinated phenolic derivatives,as well as complex chlorinated oligomer byproducts with ether structures(mainly dimers and trimers).While the formation of common chlorophenols can be ascribed to the electrophilic substitution reactions mediated by ACS,the oligomer byproducts are generated via coupling reactions between chlorinated phenoxy radicals.ECOSAR software predicts that the generated chlorinated oligomer byproducts exhibit high ecotoxicological effects.As a whole,the above findings shed light on the potential risk of FOT in real practice.展开更多
Boron-doped diamond （BDD） electrocatalysis is combined with photocatalysis using titanium dioxide （TiO2） as a catalyst to improve pollutant-oxidation efficiency. Phenol solution is chosen as model wastewater. Diff...Boron-doped diamond （BDD） electrocatalysis is combined with photocatalysis using titanium dioxide （TiO2） as a catalyst to improve pollutant-oxidation efficiency. Phenol solution is chosen as model wastewater. Different methods involving BDD and/or TiO2 during the degradation processes are compared. Parameters such as the currency density and initial concentration are varied in order to determine their effects on the oxidation process. Moreover, the degradation kinetics of phenol is experimentally studied. The results reveal the superiority of series combination of BDD and TiO2, especially the treatment process of electrocatalysis and succedent photocatalysis, and the optimum working currency density for electrocatalysis is 25.48 mA/cm2. The removal rate decreases with the increase in the initial phenol concentration and the degradation reaction follows quasi-first-order kinetics equation.展开更多
To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretre...To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.展开更多
The microbial degradation of aromatic organic pollutants is incomplete due to their metabolic characteristics,which can easily produce certain highly toxic intermediates.Therefore,this article designs a dual template ...The microbial degradation of aromatic organic pollutants is incomplete due to their metabolic characteristics,which can easily produce certain highly toxic intermediates.Therefore,this article designs a dual template molec-ularly imprinted sensor(DTMIP/Fe-Mn@C)for iron manganese metal nanomaterials,prepared Fe-Mn@C com-posite materials by a one pot method were coated on the surface of glassy carbon electrodes and covered with molecularly imprinted membranes through electropolymerization and elution methods,achieving real-time de-tection of specific intermediate products 2-methylbutyric acid(2-MBA)and 3-methylbutyric acid(3-MBA)de-graded by azo dyes.In order to determine the detection sensitivity and intensity range of the sensor,optimization experiments were conducted on various parameters that affect the detection performance,such as the type of func-tional monomer and its composition ratio with the template molecule,detection time window,environmental pH value,etc.Finally,o-Phenylenediamine was determined as the functional monomer,with a molar ratio of 1:1:6 to the template molecules 2-MBA and 3-MBA.Electrochemical testing was conducted in a neutral environment with an incubation time of 5 min and pH=7.The results indicate that the sensor has a relatively wide detection range,high sensitivity,obvious recognition features,and excellent stability for 2-MBA and 3-MBA.This new dual template molecularly imprinted sensor can quickly and accurately determine the safety of highly toxic interme-diates in the degradation process of aromatic organic pollutants,providing a theoretical basis and application potential for trace detection and real-time monitoring.展开更多
The increasing production and release of synthetic organic chemicals,including pharmaceuticals,into our envi-ronment has allowed these substances to accumulate in our surface water systems.Current purification technol...The increasing production and release of synthetic organic chemicals,including pharmaceuticals,into our envi-ronment has allowed these substances to accumulate in our surface water systems.Current purification technolo-gies have been unable to eliminate these pollutants,resulting in their ongoing release into aquatic ecosystems.This study focuses on cloperastine(CPS),a cough suppressant and antihistamine medication.The environmental impact of CPS usage has become a concern,mainly due to its increased detection during the COVID-19 pandemic.CPS has been found in wastewater treatment facilities,effluents from senior living residences,river waters,and sewage sludge.However,the photosensitivity of CPS and its photodegradation profile remain largely unknown.This study investigates the photodegradation process of CPS under simulated tertiary treatment conditions using UV photolysis,a method commonly applied in some wastewater treatment plants.Several transformation prod-ucts were identified,evaluating their kinetic profiles using chemometric approaches(i.e.,curve fitting and the hard-soft multivariate curve resolution-alternating least squares(HS-MCR-ALS)algorithm)and calculating the reaction quantum yield.As a result,three different transformation products have been detected and correctly identified.In addition,a comprehensive description of the kinetic pathway involved in the photodegradation process of the CPS drug has been provided,including observed kinetic rate constants.展开更多
Manganese oxides are known as one type of semiconductors,but their photocatalysis characteristics have not been deeply explored.In this study,photocatalytic degradation of phenol using several synthesized manganese ox...Manganese oxides are known as one type of semiconductors,but their photocatalysis characteristics have not been deeply explored.In this study,photocatalytic degradation of phenol using several synthesized manganese oxides,i.e,acidic birnessite （BIR-H）,alkaline birnessite （BIR-OH）,cryptomelane （CRY） and todorokite （TOD）,were comparatively investigated.To elucidate phenol degradation mechanisms,X-ray diffraction （XRD）,ICP-AES （inductively coupled plasma-atomic emission spectroscopy）,TEM （transmission electronic microscope）,N 2 physisorption at 77 K and UV-visible diffuse reflectance spectroscopy （UV-Vis DRS） were employed to characterize the structural,compositional,morphological,specific surface area and optical absorption properties of the manganese oxides.After 12 hr of UV-Vis irradiation,the total organic carbon （TOC） removal rate reached 62.1%,43.1%,25.4%,and 22.5% for cryptomelane,acidic birnessite,todorokite and alkaline birnessite,respectively.Compared to the reactions in the dark condition,UV- Vis exposure improved the TOC removal rates by 55.8%,31.9%,23.4% and 17.9%.This suggests a weak ability of manganese oxides to degrade phenol in the dark condition,while UV-Vis light irradiation could significantly enhance phenol degradation.The manganese minerals exhibited photocatalytic activities in the order of：CRY BIR-H TOD BIR-OH.There may be three possible mechanisms for photochemical degradation：（1） direct photolysis of phenol;（2） direct oxidation of phenol by manganese oxides;（3） photocatalytic oxidation of phenol by manganese oxides.Photocatalytic oxidation of phenol appeared to be the dominant mechanism.展开更多
TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing Ti...TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing TiB_(2)coatings have disadvantages such as high equipment costs,complicated processes,and highly toxic gas emissions.This paper proposes an environmentally friendly method,which requires inexpensive equipment and simple processing,for preparing TiB_(2)coating on molybdenum via electrophoretic deposition within Na3AlF6-based molten salts.The produced TiB_(2)layer had an approximate thickness of 60μm and exhibited high density,outstanding hardness(38.2 GPa)and robust adhesion strength(51 N).Additionally,high-temperature oxidation experiments revealed that,at900℃,the TiB_(2)coating provided effective protection to the molybdenum substrate against oxidation for 3 h.This result indicates that the TiB_(2)coating prepared on molybdenum using molten salt electrophoretic deposition possesses good high-temperature oxidation resistance.展开更多
The 2,4,6-trinitrotoluene （TNT） is a potential carcinogens and TNT contaminated wastewater, which could not be effectively disposed with conventional treatments. The supercritical water oxidation （SCWO） to treat T...The 2,4,6-trinitrotoluene （TNT） is a potential carcinogens and TNT contaminated wastewater, which could not be effectively disposed with conventional treatments. The supercritical water oxidation （SCWO） to treat TNT contaminated wastewater was studied in this article, The TNT concentration in wastewater was measured by high-performance liquid chromatograph （HPLC） and the degraded intermediates were analyzed using GC-MS. The results showed that SCWO could degrade TNT efficiently in the presence of oxygen. The reaction temperature, pressure, residence time and oxygen excess were the main contributing factors in the process. The decomposition of TNT was accelerated as the temperature or residence time increased. At 550℃, 24 MPa, 120 s and oxygen excess 300%, TNT removal rate could exceed 99.9%. Partial oxidation occured in SCWO without oxygen. It was concluded that supercritical water was a good solvent and had excellent oxidation capability in the existence of oxygen. The main intermediates of TNT during SCWO included toluene, 1,3,5-trinitrobenzene, nitrophenol, naphthalene, fluorenone, dibutyl phthalate, alkanes and several dimers based on the intermediate analysis. Some side reactions, such as coupled reaction, hydrolysis reaction and isomerization reaction may take place simultaneously when TNT was oxidized by SCWO.展开更多
A novel process, microwave assisted catalytic wet air oxidation(MW-CWO), was applied for the degradation of H-acid(1-amino-8-naphthol-3, 6-disulfonic acid) in aqueous solution. Ni-loaded granular activated carbon(GAC)...A novel process, microwave assisted catalytic wet air oxidation(MW-CWO), was applied for the degradation of H-acid(1-amino-8-naphthol-3, 6-disulfonic acid) in aqueous solution. Ni-loaded granular activated carbon(GAC), prepared by immersion-calcination method, was used as catalyst. The results showed that the MW-CWO process was very effective for the degradation of H-acid in aqueous solution under atmospheric pressure with 87.4% TOC (total organic carbon) reduction in 20 min. Ni on GAC existed in the form of NiO as specified by XRD. Loss of Ni was significant in the initial stage, and then remained almost constant after 20 min reaction. BET surface area results showed that the surface property of GAC after MW-CWO process was superior to that of blank GAC.展开更多
Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising a...Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising as SIBs cathodes due to their high theoretical capacities and facile synthesis.However,their practical applications are hindered by the limitations in energy density and cycling stability.The comprehensive understanding of failure mechanisms within bulk structure and at the cathode/electrolyte interface of cathodes is still lacking.In this review,the issues related to bulk phase degradation and surface degradation,such as irreversible phase transitions,cation migration,transition metal dissolution,air/moisture instability,intergranular cracking,interfacial reactions,and reactive oxygen loss,are discussed.The latest advances and strategies to improve the stability of layered oxide cathodes and full cells are provided,as well as our perspectives on the future development of SIBs.展开更多
The degradation capacity of advanced oxidants generated from oxygen reduction was investigated in model effluent containing chlorobenzene, aniline and benzene through the advanced oxidation processes(AOPs). Intermedia...The degradation capacity of advanced oxidants generated from oxygen reduction was investigated in model effluent containing chlorobenzene, aniline and benzene through the advanced oxidation processes(AOPs). Intermediate products of the degradation process were determined by GC–MS, and they contributed to specify the degradation pathways of monoaromatic compounds. The study particularly focused on the influence of the dosage of the oxidant, pH and the initial concentration of organic compounds on the degradation effectiveness.When the dosage of oxidant was 4 wt% and the pH was 7, the maximum degradation rates of 74.83% chlorobenzene, 70.32% aniline and 37.69% benzene were achieved. Furthermore, microwave was applied to intensify the oxidation process under optimal operation conditions, and the degradation rates were increased to 87.85% chlorobenzene, 89.11% aniline and 39.03% benzene, respectively.展开更多
Herein,we prepa red novel three-dimensional(3D)gear-s haped Co3O4@C(Co3O4 modified by amorphous carbon)and sheet-like SnO2/CC(SnO2 grow on the carbon cloth)as anode and cathode to achieve efficient removal of 4-nitrop...Herein,we prepa red novel three-dimensional(3D)gear-s haped Co3O4@C(Co3O4 modified by amorphous carbon)and sheet-like SnO2/CC(SnO2 grow on the carbon cloth)as anode and cathode to achieve efficient removal of 4-nitrophenol(4-NP)in the presence of peroxymonosulfate(PMS)and simultaneous electrocatalytic reduction of CO2,respectively.In this process,4-NP was mineralized into CO2 by the Co3O4@C,and the generated CO2 was reduced into HCOOH by the sheet-like SnO2/CC cathode.Compared with the pure Co0.5(Co3O4 was prepared using 0.5 g urea)with PMS(30 mg,0.5 g/L),the degradation efficiency of 4-NP(60 mL,10 mg/L)increased from 74.5%-85.1%in 60 min using the Co0.5 modified by amorphous carbon(Co0.5@C).Furthermore,when the voltage of 1.0 V was added in the anodic system of Co0.5@C with PMS(30 mg,0.5 g/L),the degradation efficiency of 4-NP increased from 85.1%-99.1%when Pt was used as cathode.In the experiments of 4-NP degradation coupled with simultaneous electrocatalytic CO2 reduction,the degradation efficiency of 4-NP was 99.0%in the anodic system of Co0.5@C with addition of PMS(30 mg,0.5 g/L),while the Faraday efficiency(FE)of HCOOH was 24.1%at voltage of-1.3 V using the SnO2/CC as cathode.The results showed that the anode of Co3O4 modified by amorphous carbon can markedly improve the degradation efficiency of 4-NP,while the cathode of SnO2/CC can greatly improve the FE and selectivity of CO2 reduction to HCOOH and the stability of cathode.Finally,the promotion mechanism was proposed to explain the degradation of organic pollutants and reduction of CO2 into HCOOH in the process of electrocatalysis coupled with advanced oxidation processes(AOPs)and simultaneous CO2 reduction.展开更多
Oxidation of aniline by persulfate in aqueous solutions was investigated and the reaction kinetic rates under different temperature, persulfate concentration and pH conditions were examined in batch experiments. The r...Oxidation of aniline by persulfate in aqueous solutions was investigated and the reaction kinetic rates under different temperature, persulfate concentration and pH conditions were examined in batch experiments. The results showed that, the aniline degradation followed pseudo first-order reaction model. Aniline degradation rate increased with increasing temperature or persulfate concentration. In the pH range of 3 to 11, a low aniline degradation rate was obtained at strong acid system （pH 3）, while a high degradation rate was achieved at strong alkalinity （pH 11）. Maximum aniline degradation occurred at pH 7 when the solution was in a weak level of acid and alkalinity （pH 5, 7 and 9）. Produced intermediates during the oxidation process were identified using liquid chromatography-mass spectrometry technology. And nitrobenzene, 4-4’-diaminodiphenyl and 1-hydroxy-1,2-diphenylhydrazine have been identified as the major intermediates of aniline oxidation by persulfate and the degradation mechanism of aniline was also tentatively proposed.展开更多
The electrochemical advanced oxidation processes(EAOPs) have been extensively applied in the treatment of organic pollutants degradation.Herein,the mini review provides the coupling systems about EAOPs and different o...The electrochemical advanced oxidation processes(EAOPs) have been extensively applied in the treatment of organic pollutants degradation.Herein,the mini review provides the coupling systems about EAOPs and different oxidants(e.g.,persulfate(PS),peroxymonosulfate(PMS),and ozone(O3)),including EAOPs-PS systems,EAOPs-PMS systems,EAOPs-peroxone systems,and photoelectro-oxidants systems,for the organic compounds degradation.The coupling system of EAOPs with oxidants is an effective way to improve the generated free radicals(e.g.,HO^·and SO4^·-) concentration and to accelerate pollutant degradation.In this review,we make a summary of the homogeneous and heterogeneous EAOPs-oxidant processes.The reaction mechanisms of EAOPs combined with different oxidants are elucidated in detail,as well as the synergistic effect for improving the degradation and mineralization efficiency.展开更多
Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro...Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts.展开更多
A novel high gravity multi-concentric cylinder electrodes-rotating bed(MCCE-RB) was developed for the electrocatalytic degradation of phenol wastewater in order to enhance the mass transfer with the self-made RuO_2-Ir...A novel high gravity multi-concentric cylinder electrodes-rotating bed(MCCE-RB) was developed for the electrocatalytic degradation of phenol wastewater in order to enhance the mass transfer with the self-made RuO_2-IrO_2-SnO_2/Ti anodes. The influences of electric current density, inlet liquid circulation flowrate, high gravity factor, sodium chloride concentration,and initial pH value on phenol degradation efficiency were investigated, with the optimal operating conditions determined. The results showed that under the optimal operating conditions covering a current density of 35 mA/cm^2, an inlet liquid circulation flowrate of 48 L/h, a high gravity factor of 20, a sodium chloride concentration of 8.5 g/L, an initial pH value of 6.5, a reaction time of 100 min, and an initial phenol concentration of 500 mg/L, the efficiency for removal of phenol reached 99.7%, which was improved by 10.4% as compared to that achieved in the normal gravity field. The tendency regarding the change in efficiency for removal of phenol, total organic carbon(TOC), and chemical oxygen demand(COD)over time was studied. The intermediates and degradation pathway of phenol were deduced by high performance liquid chromatography(HPLC).展开更多
基金supported by the National Natural Science Foundation of China(Nos.42477406 and 51878617)the Horizontal Scientific Research Project(No.KYY-HX-20220803)the Engineering Research Center of Ministry of Education for Renewable Energy Infrastructure Construction Technology.
文摘In this work,we constructed a three-dimensional electrochemical system(3D-ECO),which included the cathode and anode electrode plates,as well as the screening of three-dimensional particle electrodes and parameter opti-mization,for the degradation of landfill leachate(LL)containing elevated levels of tetracycline(TC),and explored its mechanism of action.Firstly,titanium-based ruthenium-iridium(Ti/RuO_(2)-IrO_(2)),titanium-based ruthenium-iridium-platinum(Ti/Pt-RuO_(2)-IrO_(2)),and titanium-based tin-antimony(Ti/SnO_(2)-Sb_(2)O_(3))were employed as an-odes in the electrocatalytic oxidation system,with titanium and stainless steel plates serving as cathodes,to construct the optimal two-dimensional electrocatalytic oxidation system(2D-ECO)through cross-comparison ex-periments.Subsequently,using granular activated carbon(GAC),coconut shell biochar(CBC),walnut shell carbon(WBC),and bamboo charcoal(BBC)as particle electrodes,a 3D-ECO system was developed.The influence of var-ious operational parameters on treating TC-containing LL was investigated.The optimal operating parameters obtained from the study was:pH=5,current density of 30 mA/cm^(2),particle dosage of 7 g/L,particle size ranging from 1.70 to 2.00 mm,and electrode spacing of 4 cm.Under these conditions,the COD removal rate of 3D-ECO within three hours was 90.25%,the TC removal rate was 72.41%,and the NH_(3)-N removal rate was 39.52%.The removal of TC followed a pseudo-first-order kinetic model.Additionally,degradation mechanisms were elucidated through electron paramagnetic resonance(EPR)spectrometer and Tert-Butanol(TBA)quenching experiments,indicating that the degradation primarily occurred through a non-radical(1O_(2))pathway.This re-search offers a comprehensive analysis of the simultaneous breakdown of intricate LL matrices and TC,enhancing our comprehension of the degradation processes and underlying mechanisms.
基金financially supported by the National Key Technology R&D Program of China(No.2021YFB3500801)
文摘Enhancing the activity of photocatalysts is a critical challenge for improving the photocatalytic degradation of contaminated wastewater.Here,a novel Ce single-atom-doped titanate nanotube photocatalyst(CeH_(2)Ti_(2)O_(5)·H_(2)O)was successfully synthesized using a onepot solvothermal method.Degradation experiments revealed that the optimal Ce doping ratio was 1.0%.The ultraviolet-visible diffuse reflectance spectroscopy results showed that the bandgap of the Ce-doped sample decreased from 3.02 to 2.87 eV,enhancing the absorption in the visible spectral range.At the same time,the BrunauerEmmett-Teller specific surface area increased from 63.68 to 88.95 m^(2)g^(-1).The 1.0%Ce-H_(2)Ti_(2)O_(5)·H_(2)O(HTC_(1))could degrade 99.04%of 100 mg L-1rhodamine B(RhB)after 40 min of visible-light irradiation.The degradation efficiency decreased by only 21.24%after five cycles.The results of free-radical quenching and electron spin resonance spectroscopy analyses indicated that HTC_(1)achieved efficient degradation of RhB through a direct hole oxidation mechanism.Compared with pure protonated titanate nanotubes(H_(2)Ti_(2)O_(5)·H_(2)O),HTC_(1)had a higher specific surface area,more electron traps,narrower bandgap,longer hole lifetime,and suppressed photogenerated charge recombination rate owing to the Ce single-atom doping.
基金supported by the National Natural Science Foundation of China(22288102)。
文摘The large molecular weight and high hydrophilicity of chloramphenicol(CAP) residuals in wastewater led to severe degradation difficulty,which propelled the development of new wastewater degradation processes and reactors based on process intensification.This study enhanced the CAP degradation by ozone/peroxydisulfate(PDS) advanced oxidation process in a submerged rotating packed bed(SRPB)reactor.Compared the usage of different oxidants,it was indicated that the combination of O_(3) and PDS exhibited a higher degradation efficiency than ozone and PDS alone.The more desired degradation efficiency could be achieved at the operating conditions of ascending PDS concentration,SRPB rotational speed,ozone concentration,reduced initial CAP concentration,and the water qualities of ascended pH,lower Cl^(-)and initial CO_(3)^(2-) concentrations.Under the optimized conditions of C_(CAP)=20 mg·L^(-1),C_(O3)=30 mg·L^(-1),C_(PDS)=100 mg·L^(-1),and N=400 r·min^(-1),and water qualities of pH=10,the maximum chloramphenicol degradation efficiency of 97% and kinetic constant of 0.23 min^(-1) were achieved after treating 16 min.A comparison of the results with previously reported advanced oxidation processes of CAP indicated that the enhanced O^(3)/PDS advanced oxidation system using the SRPB can significantly improve the degradation efficiency of CAP.
基金supported by the Natural Science Foundation of Inner Mongolia Autonomous Region of China(Grant No.2024LHMS05048).
文摘Addressing the growing challenge of water contamination,this study comparatively evaluated a persulfate(PDS)system activated by nonradical nitrogen-doped carbon nanotubes(N-CNTs)versus a PDS system activated by radical-based iron(Fe^(2+)),both used for the degradation of bisphenol A(BPA).The N-CNTs/PDS system,driven by the electron transfer mechanism,achieved remarkable 90.9%BPA removal within 30 min at high BPA concentrations,significantly outperforming the Fe^(2+)/PDS system,which attained only 38.9%removal.The N-CNTs/PDS system maintained robust degradation efficiency across a wide range of BPA concentrations and exhibited a high degree of resilience in diverse water matrices.By directly abstracting electrons from BPA molecules,the N-CNTs/PDS system effectively minimised oxidant wastage and mitigated the risk of secondary pollution,ensuring efficient utilisation of active sites on N-CNTs and sustaining a high catalytic rate.The formation of the N-CNTs-PDS^(*)complex significantly enhanced BPA degradation and mineralisation,thereby optimising PDS consumption.These findings highlight the unparalleled advantages of the N-CNTs/PDS system in managing complex wastewater,offering a promising and innovative solution for treating complex industrial wastewater and advancing environmental remediation efforts.
基金supported by the Fundamental Research Funds for the Central Universities(Nos.KYCYXT2023001,and XUEKEN2022034).
文摘Currently,ferrate(VI)oxidation technology(FOT)has been regarded as one of the most promising options for the degradation of emerging organic pollutants.However,the role and transformation of chloride ions(Cl^(−))in FOT have not been well explored.The current study aims to investigate the formation of chlorinated phenolic byproducts upon ferrate(VI)oxidation processes.The obtained results indicate that chlorides suffering ferrate(VI)attack will be transformed to active chlorine species(ACS),which will subsequently lead to the formation of highly toxic aromatic chlorinated byproducts.The identified byproducts include common chlorinated phenolic derivatives,as well as complex chlorinated oligomer byproducts with ether structures(mainly dimers and trimers).While the formation of common chlorophenols can be ascribed to the electrophilic substitution reactions mediated by ACS,the oligomer byproducts are generated via coupling reactions between chlorinated phenoxy radicals.ECOSAR software predicts that the generated chlorinated oligomer byproducts exhibit high ecotoxicological effects.As a whole,the above findings shed light on the potential risk of FOT in real practice.
基金The Key Project of Chinese Ministry of Education (No.108601)Major Projects of National Water Pollution Control and Management Technology (No.2009ZX07101-011)Specialized Research Fund for the Doctoral Program of Higher Education (No.20060286010)
文摘Boron-doped diamond （BDD） electrocatalysis is combined with photocatalysis using titanium dioxide （TiO2） as a catalyst to improve pollutant-oxidation efficiency. Phenol solution is chosen as model wastewater. Different methods involving BDD and/or TiO2 during the degradation processes are compared. Parameters such as the currency density and initial concentration are varied in order to determine their effects on the oxidation process. Moreover, the degradation kinetics of phenol is experimentally studied. The results reveal the superiority of series combination of BDD and TiO2, especially the treatment process of electrocatalysis and succedent photocatalysis, and the optimum working currency density for electrocatalysis is 25.48 mA/cm2. The removal rate decreases with the increase in the initial phenol concentration and the degradation reaction follows quasi-first-order kinetics equation.
基金National Natural Science Foundation of China(52071274)Key Research and Development Projects of Shaanxi Province(2023-YBGY-442)Science and Technology Nova Project-Innovative Talent Promotion Program of Shaanxi Province(2020KJXX-062)。
文摘To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.
基金supported by the Bingtuan Industrial Technology Research Institute,Bingtuan New materials Research Institute innovation platform project,Research initiation project of Shihezi University(No.RCZK202330)the Science and Technology Program-Regional Innovation Guidance Program(No.2023ZD080)Tianchi Talent Project(No.CZ002735).
文摘The microbial degradation of aromatic organic pollutants is incomplete due to their metabolic characteristics,which can easily produce certain highly toxic intermediates.Therefore,this article designs a dual template molec-ularly imprinted sensor(DTMIP/Fe-Mn@C)for iron manganese metal nanomaterials,prepared Fe-Mn@C com-posite materials by a one pot method were coated on the surface of glassy carbon electrodes and covered with molecularly imprinted membranes through electropolymerization and elution methods,achieving real-time de-tection of specific intermediate products 2-methylbutyric acid(2-MBA)and 3-methylbutyric acid(3-MBA)de-graded by azo dyes.In order to determine the detection sensitivity and intensity range of the sensor,optimization experiments were conducted on various parameters that affect the detection performance,such as the type of func-tional monomer and its composition ratio with the template molecule,detection time window,environmental pH value,etc.Finally,o-Phenylenediamine was determined as the functional monomer,with a molar ratio of 1:1:6 to the template molecules 2-MBA and 3-MBA.Electrochemical testing was conducted in a neutral environment with an incubation time of 5 min and pH=7.The results indicate that the sensor has a relatively wide detection range,high sensitivity,obvious recognition features,and excellent stability for 2-MBA and 3-MBA.This new dual template molecularly imprinted sensor can quickly and accurately determine the safety of highly toxic interme-diates in the degradation process of aromatic organic pollutants,providing a theoretical basis and application potential for trace detection and real-time monitoring.
基金supported by the grants PID2020-113371RA-C22 and TED2021-130845A-C32,funded by MCIN/AEI/10.13039/501100011033.M.Marín-García,R.González-OlmosC.Gómez-Canela are members of the GESPA group(Grup d’Enginyeria i Simulacióde Processos Ambientals)at IQS-URL,which has been acknowledged as a Consolidated Research Group by the Government of Catalonia(No.2021-SGR-00321)+1 种基金In addition,M.Marín-García has been awarded a public grant for the Investigo Programme,aimed at hiring young job seekers to undertake research and innovation projects under the Recovery,Transformation,and Resilience Plan(PRTR),European Union Next Generation,for the year 2022,through the Government of Catalonia and the Spanish Ministry for Work and Social Economy(No.100045ID16)Ana Belén Cuenca for her support and expertise,which helped to confirm the proposed reaction mechanism involved in the UV photolysis of cloperastine.
文摘The increasing production and release of synthetic organic chemicals,including pharmaceuticals,into our envi-ronment has allowed these substances to accumulate in our surface water systems.Current purification technolo-gies have been unable to eliminate these pollutants,resulting in their ongoing release into aquatic ecosystems.This study focuses on cloperastine(CPS),a cough suppressant and antihistamine medication.The environmental impact of CPS usage has become a concern,mainly due to its increased detection during the COVID-19 pandemic.CPS has been found in wastewater treatment facilities,effluents from senior living residences,river waters,and sewage sludge.However,the photosensitivity of CPS and its photodegradation profile remain largely unknown.This study investigates the photodegradation process of CPS under simulated tertiary treatment conditions using UV photolysis,a method commonly applied in some wastewater treatment plants.Several transformation prod-ucts were identified,evaluating their kinetic profiles using chemometric approaches(i.e.,curve fitting and the hard-soft multivariate curve resolution-alternating least squares(HS-MCR-ALS)algorithm)and calculating the reaction quantum yield.As a result,three different transformation products have been detected and correctly identified.In addition,a comprehensive description of the kinetic pathway involved in the photodegradation process of the CPS drug has been provided,including observed kinetic rate constants.
基金supported by the National Natural Sci-ence Foundation of China(No.40830527,40771102)the New Century Excellent Talents in University of China(No.NCET-09-0399)
文摘Manganese oxides are known as one type of semiconductors,but their photocatalysis characteristics have not been deeply explored.In this study,photocatalytic degradation of phenol using several synthesized manganese oxides,i.e,acidic birnessite （BIR-H）,alkaline birnessite （BIR-OH）,cryptomelane （CRY） and todorokite （TOD）,were comparatively investigated.To elucidate phenol degradation mechanisms,X-ray diffraction （XRD）,ICP-AES （inductively coupled plasma-atomic emission spectroscopy）,TEM （transmission electronic microscope）,N 2 physisorption at 77 K and UV-visible diffuse reflectance spectroscopy （UV-Vis DRS） were employed to characterize the structural,compositional,morphological,specific surface area and optical absorption properties of the manganese oxides.After 12 hr of UV-Vis irradiation,the total organic carbon （TOC） removal rate reached 62.1%,43.1%,25.4%,and 22.5% for cryptomelane,acidic birnessite,todorokite and alkaline birnessite,respectively.Compared to the reactions in the dark condition,UV- Vis exposure improved the TOC removal rates by 55.8%,31.9%,23.4% and 17.9%.This suggests a weak ability of manganese oxides to degrade phenol in the dark condition,while UV-Vis light irradiation could significantly enhance phenol degradation.The manganese minerals exhibited photocatalytic activities in the order of：CRY BIR-H TOD BIR-OH.There may be three possible mechanisms for photochemical degradation：（1） direct photolysis of phenol;（2） direct oxidation of phenol by manganese oxides;（3） photocatalytic oxidation of phenol by manganese oxides.Photocatalytic oxidation of phenol appeared to be the dominant mechanism.
基金supported by the Original Exploratory Program of the National Natural Science Foundation of China(No.52450012)。
文摘TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing TiB_(2)coatings have disadvantages such as high equipment costs,complicated processes,and highly toxic gas emissions.This paper proposes an environmentally friendly method,which requires inexpensive equipment and simple processing,for preparing TiB_(2)coating on molybdenum via electrophoretic deposition within Na3AlF6-based molten salts.The produced TiB_(2)layer had an approximate thickness of 60μm and exhibited high density,outstanding hardness(38.2 GPa)and robust adhesion strength(51 N).Additionally,high-temperature oxidation experiments revealed that,at900℃,the TiB_(2)coating provided effective protection to the molybdenum substrate against oxidation for 3 h.This result indicates that the TiB_(2)coating prepared on molybdenum using molten salt electrophoretic deposition possesses good high-temperature oxidation resistance.
基金Project supported by the Science Technology Foundation of Educational Department(No.204020).
文摘The 2,4,6-trinitrotoluene （TNT） is a potential carcinogens and TNT contaminated wastewater, which could not be effectively disposed with conventional treatments. The supercritical water oxidation （SCWO） to treat TNT contaminated wastewater was studied in this article, The TNT concentration in wastewater was measured by high-performance liquid chromatograph （HPLC） and the degraded intermediates were analyzed using GC-MS. The results showed that SCWO could degrade TNT efficiently in the presence of oxygen. The reaction temperature, pressure, residence time and oxygen excess were the main contributing factors in the process. The decomposition of TNT was accelerated as the temperature or residence time increased. At 550℃, 24 MPa, 120 s and oxygen excess 300%, TNT removal rate could exceed 99.9%. Partial oxidation occured in SCWO without oxygen. It was concluded that supercritical water was a good solvent and had excellent oxidation capability in the existence of oxygen. The main intermediates of TNT during SCWO included toluene, 1,3,5-trinitrobenzene, nitrophenol, naphthalene, fluorenone, dibutyl phthalate, alkanes and several dimers based on the intermediate analysis. Some side reactions, such as coupled reaction, hydrolysis reaction and isomerization reaction may take place simultaneously when TNT was oxidized by SCWO.
基金The Hi Tech Research and Development Program(863) of China(No. 2002AA649090) and the National Basic Research Program(973) of China(No.2003CB415006)
文摘A novel process, microwave assisted catalytic wet air oxidation(MW-CWO), was applied for the degradation of H-acid(1-amino-8-naphthol-3, 6-disulfonic acid) in aqueous solution. Ni-loaded granular activated carbon(GAC), prepared by immersion-calcination method, was used as catalyst. The results showed that the MW-CWO process was very effective for the degradation of H-acid in aqueous solution under atmospheric pressure with 87.4% TOC (total organic carbon) reduction in 20 min. Ni on GAC existed in the form of NiO as specified by XRD. Loss of Ni was significant in the initial stage, and then remained almost constant after 20 min reaction. BET surface area results showed that the surface property of GAC after MW-CWO process was superior to that of blank GAC.
基金supported by the National Natural Science Foundation of China(Grant No.W2412060,22325902 and 52171215)the State Key Laboratory of Clean Energy Utilization(Open Fund Project No.ZJUCEU2023002)。
文摘Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising as SIBs cathodes due to their high theoretical capacities and facile synthesis.However,their practical applications are hindered by the limitations in energy density and cycling stability.The comprehensive understanding of failure mechanisms within bulk structure and at the cathode/electrolyte interface of cathodes is still lacking.In this review,the issues related to bulk phase degradation and surface degradation,such as irreversible phase transitions,cation migration,transition metal dissolution,air/moisture instability,intergranular cracking,interfacial reactions,and reactive oxygen loss,are discussed.The latest advances and strategies to improve the stability of layered oxide cathodes and full cells are provided,as well as our perspectives on the future development of SIBs.
基金Supported by the Key Technologies R&D Program of China(2011BAE111300)
文摘The degradation capacity of advanced oxidants generated from oxygen reduction was investigated in model effluent containing chlorobenzene, aniline and benzene through the advanced oxidation processes(AOPs). Intermediate products of the degradation process were determined by GC–MS, and they contributed to specify the degradation pathways of monoaromatic compounds. The study particularly focused on the influence of the dosage of the oxidant, pH and the initial concentration of organic compounds on the degradation effectiveness.When the dosage of oxidant was 4 wt% and the pH was 7, the maximum degradation rates of 74.83% chlorobenzene, 70.32% aniline and 37.69% benzene were achieved. Furthermore, microwave was applied to intensify the oxidation process under optimal operation conditions, and the degradation rates were increased to 87.85% chlorobenzene, 89.11% aniline and 39.03% benzene, respectively.
基金the National Natural Science Foundation of China(Nos.51878325,51868050,51622806,51378246 and 51720105001)the Natural Science Foundation of Jiangxi Province(Nos.20162BCB22017,20165BCB18008,20171ACB20017,20133ACB21001 and 20171BAB206049)the Graduate Innovation Fund of Jiangxi Province(No.YC2018-S360)。
文摘Herein,we prepa red novel three-dimensional(3D)gear-s haped Co3O4@C(Co3O4 modified by amorphous carbon)and sheet-like SnO2/CC(SnO2 grow on the carbon cloth)as anode and cathode to achieve efficient removal of 4-nitrophenol(4-NP)in the presence of peroxymonosulfate(PMS)and simultaneous electrocatalytic reduction of CO2,respectively.In this process,4-NP was mineralized into CO2 by the Co3O4@C,and the generated CO2 was reduced into HCOOH by the sheet-like SnO2/CC cathode.Compared with the pure Co0.5(Co3O4 was prepared using 0.5 g urea)with PMS(30 mg,0.5 g/L),the degradation efficiency of 4-NP(60 mL,10 mg/L)increased from 74.5%-85.1%in 60 min using the Co0.5 modified by amorphous carbon(Co0.5@C).Furthermore,when the voltage of 1.0 V was added in the anodic system of Co0.5@C with PMS(30 mg,0.5 g/L),the degradation efficiency of 4-NP increased from 85.1%-99.1%when Pt was used as cathode.In the experiments of 4-NP degradation coupled with simultaneous electrocatalytic CO2 reduction,the degradation efficiency of 4-NP was 99.0%in the anodic system of Co0.5@C with addition of PMS(30 mg,0.5 g/L),while the Faraday efficiency(FE)of HCOOH was 24.1%at voltage of-1.3 V using the SnO2/CC as cathode.The results showed that the anode of Co3O4 modified by amorphous carbon can markedly improve the degradation efficiency of 4-NP,while the cathode of SnO2/CC can greatly improve the FE and selectivity of CO2 reduction to HCOOH and the stability of cathode.Finally,the promotion mechanism was proposed to explain the degradation of organic pollutants and reduction of CO2 into HCOOH in the process of electrocatalysis coupled with advanced oxidation processes(AOPs)and simultaneous CO2 reduction.
基金supported by the Foundation of Science and Technology Planning Project of Guangdong Province(No. 2010B050200007)the Fundamental Research Funds for the Central Universities (No. 2011ZM0054)the Research Fund Program of Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (China) (No. 2011K0013)
文摘Oxidation of aniline by persulfate in aqueous solutions was investigated and the reaction kinetic rates under different temperature, persulfate concentration and pH conditions were examined in batch experiments. The results showed that, the aniline degradation followed pseudo first-order reaction model. Aniline degradation rate increased with increasing temperature or persulfate concentration. In the pH range of 3 to 11, a low aniline degradation rate was obtained at strong acid system （pH 3）, while a high degradation rate was achieved at strong alkalinity （pH 11）. Maximum aniline degradation occurred at pH 7 when the solution was in a weak level of acid and alkalinity （pH 5, 7 and 9）. Produced intermediates during the oxidation process were identified using liquid chromatography-mass spectrometry technology. And nitrobenzene, 4-4’-diaminodiphenyl and 1-hydroxy-1,2-diphenylhydrazine have been identified as the major intermediates of aniline oxidation by persulfate and the degradation mechanism of aniline was also tentatively proposed.
基金the financial support from the National Natural Science Foundation of China(No. 51878423)Graduate Student’s Research and Innovation Fund of Sichuan University(No.2018YJSY075)
文摘The electrochemical advanced oxidation processes(EAOPs) have been extensively applied in the treatment of organic pollutants degradation.Herein,the mini review provides the coupling systems about EAOPs and different oxidants(e.g.,persulfate(PS),peroxymonosulfate(PMS),and ozone(O3)),including EAOPs-PS systems,EAOPs-PMS systems,EAOPs-peroxone systems,and photoelectro-oxidants systems,for the organic compounds degradation.The coupling system of EAOPs with oxidants is an effective way to improve the generated free radicals(e.g.,HO^·and SO4^·-) concentration and to accelerate pollutant degradation.In this review,we make a summary of the homogeneous and heterogeneous EAOPs-oxidant processes.The reaction mechanisms of EAOPs combined with different oxidants are elucidated in detail,as well as the synergistic effect for improving the degradation and mineralization efficiency.
基金the financial support from the National Natural Science Foundation of China(52172110,52472231,52311530113)Shanghai"Science and Technology Innovation Action Plan"intergovernmental international science and technology cooperation project(23520710600)+1 种基金Science and Technology Commission of Shanghai Municipality(22DZ1205600)the Central Guidance on Science and Technology Development Fund of Zhejiang Province(2024ZY01011)。
文摘Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts.
基金financially supported by the Nature Science Foundation of China (Grant No.U1610106)the Nature Science Foundation of China (Grant No.21703208)
文摘A novel high gravity multi-concentric cylinder electrodes-rotating bed(MCCE-RB) was developed for the electrocatalytic degradation of phenol wastewater in order to enhance the mass transfer with the self-made RuO_2-IrO_2-SnO_2/Ti anodes. The influences of electric current density, inlet liquid circulation flowrate, high gravity factor, sodium chloride concentration,and initial pH value on phenol degradation efficiency were investigated, with the optimal operating conditions determined. The results showed that under the optimal operating conditions covering a current density of 35 mA/cm^2, an inlet liquid circulation flowrate of 48 L/h, a high gravity factor of 20, a sodium chloride concentration of 8.5 g/L, an initial pH value of 6.5, a reaction time of 100 min, and an initial phenol concentration of 500 mg/L, the efficiency for removal of phenol reached 99.7%, which was improved by 10.4% as compared to that achieved in the normal gravity field. The tendency regarding the change in efficiency for removal of phenol, total organic carbon(TOC), and chemical oxygen demand(COD)over time was studied. The intermediates and degradation pathway of phenol were deduced by high performance liquid chromatography(HPLC).
