In this paper,the recent progress of simultaneous removal of SO_2 and NO_x process at home and abroad is reviewed.We mainly introduced calcium based absorbent catalytic oxidation method,complexation absorption process...In this paper,the recent progress of simultaneous removal of SO_2 and NO_x process at home and abroad is reviewed.We mainly introduced calcium based absorbent catalytic oxidation method,complexation absorption process,Electron beam method et al,principle of each technology are described,and the development direction was put forward in the future.展开更多
The coexistence of emerging containments,such as antibiotic resistant bacteria(ARB),antibiotic-resistant genes(ARGs)and antibiotics,potentially influence elimination efficiencies in UV light-emitting diode(UV-LED)alon...The coexistence of emerging containments,such as antibiotic resistant bacteria(ARB),antibiotic-resistant genes(ARGs)and antibiotics,potentially influence elimination efficiencies in UV light-emitting diode(UV-LED)alone and UV-LED/H_(2)O_(2) system as their complex interactions.Tetracycline(TC)degradation efficiency(kF)correlated closely with its UV molar absorbance(R^(2)=0.831)in UV-LED alone system and with·OH yield(R^(2)=0.999)in UV-LED/H_(2)O_(2) system across studied wavelengths(265,280 and 310 nm).The kF values for intracellular DNA(i-ARGs)also exhibited a high correlation with UV-LED wavelengths in both systems(R^(2)=0.997-0.999).The coexistence of TC and ARB/ARGs resulted in a mutual inhibition of their degradation efficiencies due to competition for photons and·OH,along with the consequent reduction in intracellular ROS within ARB,with their degradation efficiencies exhibiting marked dependence on wavelength in both systems.Notably,the UV-LED/H_(2)O_(2) system at 265 nm effectively achieved the simultaneous removal of TC,ARB and ARGs with minimal energy consumption,and successfully fragmented ARGs.The degradation pathway of TC was analyzed,and the biotoxicity of its degradation intermediates demonstrated the environmental friendliness and safety of UV-LED/H_(2)O_(2) technology.This study elucidated the competitive interactions between antibiotics and ARB/ARGs within UV-LED/H_(2)O_(2) system,providing a promising approach for their simultaneous removal while ensuring energy efficiency.展开更多
Nitric oxide （NO） removal and sulfur dioxide （SO2） removal by sodium persulfate （Na2S2O8） were studied in a Bubble Column Reactor. The proposed reaction pathways of NO and SO2 removal are discussed. The effects ...Nitric oxide （NO） removal and sulfur dioxide （SO2） removal by sodium persulfate （Na2S2O8） were studied in a Bubble Column Reactor. The proposed reaction pathways of NO and SO2 removal are discussed. The effects of temperatures （35-90℃）, Na25208 （0.05-0.5 mol·L-1）, FeSO4 （0.5-5.0 m mol·L-1） and H2O2 （0.25 mol·L-1） on NO and SO2 removal were investigated. The results indicated that increased persulfate concentration led to increase in NO removal at various temperatures. SO2 was almost completely removed in the temperature range of 55-85 ℃. Fe2 ＋ accelerated persulfate activation and enhanced NO removal efficiency. At 0.2 mol· L- 1 Na2S2O8 and 0.5-1.0 mmol· L-1Fe2 ＋, NO removal of 93.5%-99% was obtained at 75-90 ℃, SO2 removal was higher than 99% at all temperatures. The addition of 0.25 mol. L i H202 into 0.2 mol·L-1· Na2S2O8 solution promoted NO removal efficiency apparently until utterly decomposition of H2O2, the SO2 removal was as high as 98.4% separately at 35 ℃ and 80 ℃.展开更多
The removal of harmful cyanobacterial blooms(HCBs)and reuse of the resulting algal sludge are pressing issues in current environmental governance and ecological conservation.Aiming at tackling the abovementioned chall...The removal of harmful cyanobacterial blooms(HCBs)and reuse of the resulting algal sludge are pressing issues in current environmental governance and ecological conservation.Aiming at tackling the abovementioned challenges,titanium(Ti)-based coagulants are promising candidates.However,most of them suffer from poor stability and weak actual algal removal ability,and recycling of the algal sludge usually produces titanium dioxide(TiO_(2))with low photocatalytic ability.In this work,a lanthanum(La)-modified polytitanium chloride(La-PTC)coagulant is reported.La in the La-PTC coagulant serves a"kill two birds with one stone"strategy in algae removal and algae sludge reuse.Owing to the introduction of La ions,the La-PTC coagulant exhibits ultra-high stability and excellent algae removal capability with an efficiency of 98.71%,which is 7.25%higher than that of PTC coagulant.Moreover,recycling algae sludge can prepare high catalytic(2.45 times the commercial P25 TiO_(2))La/C-TiO_(2),where the presence of La enhances its visible light response range and inhibits electron hole recombination.The strategy of this La modified coagulant can not only achieve efficient re moval of HCBs,but also transfo rm the recovered algal sludge into photocatalysts with higher catalytic capacity.展开更多
The application of photocatalytic technology in algae killing is limited by the non-floatability and difficulty in recycling of the photocatalysts.Loading photocatalyst on magnetic or floatable carriers is the most po...The application of photocatalytic technology in algae killing is limited by the non-floatability and difficulty in recycling of the photocatalysts.Loading photocatalyst on magnetic or floatable carriers is the most popular method for overcoming the above inadequacies.In this work,a CdZnS/TiO_(2) membrane photocatalyst with adjustable suspended depth(include floating)and flexible assembly is designed,which is less prone to dislodgement due to in situ synthesis and has a wider range of applicability than previously reported photocatalysts.The photocatalytic removal of Microcystis aeruginosa revealed that the suspended depth and distribution format of the CdZnS/TiO_(2) membrane photocatalysts have striking effects on the photocatalytic removal performance of Microcystis aeruginosa,the photocatalytic removal efficiency of CdZnS/TiO_(2)-2 membrane photocatalysts for Microcystis aeruginosa could reach to 98.6%in 60 min when the photocatalysts assembled in the form of 3×3 arrays suspended at a depth of 2 cm from the liquid surface.A tiny amount of TiO_(2) loading allows the formation of Z-Scheme heterojunction,resulting in accelerating the separation efficiency of photogenerated carriers,preserving the photogenerated electrons and holes with stronger reduction and oxidation ability and inhabiting the photo-corrosion of CdZnS.展开更多
Heterotrophic denitrification based on polylactic acid(PLAHD)can remove nitrate effectively,but it is expensive and can't remove phosphate.Autotrophic denitrification based on iron sulfide(ISAD)can simultaneously ...Heterotrophic denitrification based on polylactic acid(PLAHD)can remove nitrate effectively,but it is expensive and can't remove phosphate.Autotrophic denitrification based on iron sulfide(ISAD)can simultaneously remove nitrate and phosphate cost-effectively,but its nitrate rate is slow.So,iron sulfide mineral/polylactic acid mixotrophic biofilter(ISPLAB)was constructed to combine advantages of ISAD and PLAHD.ISPLAB achieved nitrogen and phosphorus removal rates of 98.04%and 94.12%,respectively,at a hydraulic retention time(HRT)of 24 h.The study also revealed that controlling molecular weight(MW)of PLA improved the release of soluble organic matter;adding iron sulfide enhanced the hydrolysis of PLA and precipitated PO_(4)^(3-) of Fe^(2+)/Fe^(3+),thereby facilitated simultaneous nitrogen and phosphorus removal.Microbial community analysis resulted that denitrifying bacterias(Phaeodactylibacter and Methylotenera),sulfur-reducing bacterias(Hyphomicrobium),sulfur-oxidizing bacteria(Denitratisoma),iron-reducing bacteria(Romboutsia)and hydrolyzed bacterias(norank_f_norank_o_1-20 and norank_f_Caldilineaceae)coexisted in the ISPLAB system.Organics and iron sulfide drived the denitrification process in ISPLAB.展开更多
This study aims to optimize the use of lacquer residue biomass(LBM).We investigated the ability of LBM to remove Pb^(2+)heavy metal ions and the typical cationic dye methylene blue(MB)and anionic dye Congo red(CR)by s...This study aims to optimize the use of lacquer residue biomass(LBM).We investigated the ability of LBM to remove Pb^(2+)heavy metal ions and the typical cationic dye methylene blue(MB)and anionic dye Congo red(CR)by simultaneous adsorption from composite systems,as well as the relevant factors.Scanning electron microscopy(SEM),X-ray diffraction(XRD),and Fourier transform infrared spectroscopy(FTIR)were used to characterize adsorption behavior.The adsorption kinetics of Pb^(2+)-MB/CR composite systems can be effectively characterized by the pseudo-second-order kinetic model(R^(2)>0.97).In the Pb^(2+)-MB composite system,adsorption was antagonistic with similar adsorption sites.However,in the Pb^(2+)-CR composite system,we found that adsorption was synergistic with different adsorption sites,which led to a higher simultaneous adsorption capacity for a higher initial Pb^(2+)-CR concentration,unlike the Pb^(2+)-MB system.In both composite systems,an appropriate increase in LBM dosage and system temperature within a certain range was conducive to simultaneous adsorption and removal of Pb^(2+)-MB/CR composite systems.The optimal solid-liquid ratio and temperature were 1:75 and 30℃,respectively.The adsorption and removal rates of Pb^(2+)and MB were 99.98%and 90.49%,respectively,and those of Pb^(2+)and CR were 93.99%and 77.39%,respectively,in(50,50)mg/L of Pb^(2+)-MB/CR composite systems under these conditions.Adsorption removal of Pb^(2+)and MB improved with higher pH levels,and worsened with the increase of ionic strength in the solution,while the removal rate of CR showed an opposite trend.The coexisting anion and cation types had limited influence on the simultaneous adsorption removal of Pb^(2+),MB,and CR.The results of desorption showed that LBM can be utilized as a disposable material for simultaneously treating Pb^(2+)-MB/CR composite systems.The simultaneous adsorption mechanisms of Pb^(2+)-MB/CR mainly involved hydrogen bonding,π-πbonding interaction,and electrostatic interaction.展开更多
Two-dimensional black phosphorus(2D BP)utilized in flame retardant applications frequently encounters significant challenges,including inadequate ambient stability and elevated carbon monoxide(CO)release rates.To miti...Two-dimensional black phosphorus(2D BP)utilized in flame retardant applications frequently encounters significant challenges,including inadequate ambient stability and elevated carbon monoxide(CO)release rates.To mitigate these issues,an effective approach was proposed for the fabrication of 2D heterostructures comprising copper oxide intercalated with BP in this work.This methodology takes into account both thermodynamic and kinetic factors,resulting in substantial enhancements in the ambient stability of BP and the catalytic performance for CO elimination,achieved through the synergistic interactions between 2D BP and copper oxide,all while preserving the structural integrity of 2D BP.The incorporation of gelatin and kosmotropic anions facilitated the efficient adhesion of the multifunctional heterostructures to the flammable flexible polyurethane foam(FPUF),which not only scavenged free radicals in the gas phase but also catalyzed the formation of a dense carbon layer in the condensed phase.Kosmotropic anions induce a salting-out effect that fosters the development of a chain bundle,a hydrophobic interaction domain,and a potential microphase separation region within the gelatin chains,leading to a marked improvement in the mechanical strength of the heterostructure coatings.The modified FPUF exhibited a high limiting oxygen index(LOI)value of 34%,alongside significantly improved flame resistance:the peak CO release rate was reduced by 78%,the peak heat release rate decreased by 57%,and the fire performance index(FPI)was increased by 40 times compared to untreated FPUF.The 2D heterostructure coatings demonstrated better CO catalytic removal performance relative to previously reported flame retardant products.This research offers a promising design principle for the development of next-generation high-performance flame retardant coatings aimed at enhancing fire protection.展开更多
The Mn-Ce-Nb-O_x/P84 catalytic filter for removal of particulates and NO simultaneous was prepared by a novel method(foam coating method). The process parameters including the concentrations of PTFE emulsion, particle...The Mn-Ce-Nb-O_x/P84 catalytic filter for removal of particulates and NO simultaneous was prepared by a novel method(foam coating method). The process parameters including the concentrations of PTFE emulsion, particle size of catalyst and calcination temperature for preparation of catalytic filters were analyzed. In addition, the physical properties and performance for removal of NO(NH_3-SCR) and particulates of Mn-Ce-Nb-O_x/P84 catalytic filter prepared under the optimized parameters, were also systematic studied. Results show that the process parameters had significant influences on stability and performance of catalytic filter, The Mn-Ce-Nb-O_x/P84 catalytic filter prepared by foam coating method under the optimized parameters, has satisfactory physical properties and catalytic performance for removal of NO and particulates at 140-220 ℃. The NO removal efficiency of catalytic filter can reach95.3% at 200 ℃ as the catalyst loading amount is 450 g/m^2, Moreover,the dust removal efficiency of MnGe-Nb-O_x/P84 catalytic filter reaches as high as 99.98%, and the PM2.5 removal efficiency also reaches99.98%. The anti-sulfur performance of Mn-Ce-Nb-O_x catalytic filter is also attractive, after injecting150 ppm SO_2, the NO removal efficiency still retains up to 85%. It is indicated that the foam coating method can not only make a bond of high strength between catalyst and filter, but also make the catalytic filter possessing an excellent and stable performance for removal of NO and particulates.展开更多
Cadmium(Cd),lead(Pb),and hexavalent chromium(Cr(Ⅵ)) are often found in soils and water affected by metal smelting,chemical manufacturing,and electroplating.In this study,synthetic iron sulfide nanoparticles(FeS NPs) ...Cadmium(Cd),lead(Pb),and hexavalent chromium(Cr(Ⅵ)) are often found in soils and water affected by metal smelting,chemical manufacturing,and electroplating.In this study,synthetic iron sulfide nanoparticles(FeS NPs) were stabilized with carboxymethyl cellulose(CMC) and utilized to remove Cr(Ⅵ),Cd,and Pb from an aqueous solution.Batch experiments,a Visual MINTEQ model,scanning electron microscopy(SEM),X-ray diffraction(XRD),and X-ray photoelectron spectrometer(XPS) analysis were used to determine the removal efficiencies,influencing factors,and mechanisms.The FeS NP suspension simultaneously removed Cr(Ⅵ),Cd,and Pb from an aqueous solution.The concentrations of Cr(Ⅵ),Cd,and Pb decreased from 50,10,and 50 mg·L^(-1) to 2.5,0.1,and 0.1 mg·L^(-1),respectively.The removal capacities were up to 418,96,and 585 mg per gram of stabilized FeS NPs,respectively.The acidic conditions significantly favored the removal of aqueous Cr(Ⅵ) while the alkaline conditions favored the removal of Cd and Pb.Oxygen slightly inhibited the removal of Cr(Ⅵ),but it had no significant influence on the removal of Cd and Pb.A potential mechanism was proposed for the simultaneous removal of Cr(Ⅵ),Cd,and Pb using FeS NPs.The interactions of the three heavy metals involved a cationic bridging effect on Cr(Ⅵ) by Cd,an enhanced adsorption effect on Cd by [Cr,Fe](OH)_3,precipitation of PbCrO_4,and transformation of PbCrO_4 to PbS.Therefore,FeS NPs have a high potential for use in the simultaneous removal of Cr(Ⅵ),Cd,and Pb from contaminated aqueous solutions.展开更多
The simultaneous removal of SO_(2),NO_(x)and Hg^(0)from industrial exhaust flue gas has drawn worldwide attention in recent years.A particularly attractive technique is selective catalytic reduction,which effectively ...The simultaneous removal of SO_(2),NO_(x)and Hg^(0)from industrial exhaust flue gas has drawn worldwide attention in recent years.A particularly attractive technique is selective catalytic reduction,which effectively removes SO_(2),NO_(x)and Hg^(0)at low temperatures.This paper first reviews the simultaneous removal of SO_(2),NO_(x)and Hg^(0)by unsupported and supported catalysts.It then describes and compares the research progress of various carriers,eg.,carbon-based materials,metal oxides,silica,molecular sieves,metal-organic frameworks,and pillared interlayered clays,in the simultaneous removal of SO_(2),NO_(x)and Hg^(0).The effects of flue-gas components(such as O_(2),NH3,HCl,H2 O,SO_(2),NO and Hg^(0))on the removal of SO_(2),NOx,and Hg^(0)are discussed comprehensively and systematically.After summarizing the pollutantremoval mechanism,the review discusses future developments in the simultaneous removal of SO_(2),NOx and Hg^(0)by catalysts.展开更多
In order to investigate the feasibility of sequential removal NO and SO2 using non-thermal plasma and adsorbent simultaneously, the removal of NO and SO2 from dry gas stream （NO/SO2/N2/O2） with very little O2 using ...In order to investigate the feasibility of sequential removal NO and SO2 using non-thermal plasma and adsorbent simultaneously, the removal of NO and SO2 from dry gas stream （NO/SO2/N2/O2） with very little O2 using non-thermal plasma was investigated using a coaxial dielectric barrier discharge. Comparative experiments were carried out in the dry gas stream with and without Ar respectively at O2 concentration of 0.1%. The results showed that NO could be removed remarkably and it would be enhanced in the presence of Ar in the dry gas stream. It seems that SO2 could not be removed unless there is Ar in the dry gas stream. The mechanism of removal of NO and SO2 in the dry gas stream was discussed.展开更多
The simultaneous removal of NOx and particulate matter(PM) from diesel exhaust is investigated over a mixed metal oxide catalyst of La 0.9 K 0.1 CoO 3 loaded on γ-Al 2O 3 spherules with the assistant of pl...The simultaneous removal of NOx and particulate matter(PM) from diesel exhaust is investigated over a mixed metal oxide catalyst of La 0.9 K 0.1 CoO 3 loaded on γ-Al 2O 3 spherules with the assistant of plasma. It was found that NOx was reduced by PM in oxygen rich atmosphere, the CO 2 and N 2 were produced in the same temperature window without considering the N 2 formed by plasma decomposition. As a result, the temperature for the PM combustion decreases and the reduction efficiency of NOx to N 2 increases during the plasma process, which indicated that the activity of the catalyst can be improved by plasma. The NOx is decomposed by plasma at both low temperature and high temperature. Therefore, the whole efficiency of NOx conversion is enhanced.展开更多
Herein,a series of niobium oxide supported cerium nanotubes(Ce NTs)catalysts with different loading amount of Nb_(2)O_(5)(0–10 wt.%)were prepared and used for selective catalytic reduction of NOxwith NH_(3)(NH_(3)-SC...Herein,a series of niobium oxide supported cerium nanotubes(Ce NTs)catalysts with different loading amount of Nb_(2)O_(5)(0–10 wt.%)were prepared and used for selective catalytic reduction of NOxwith NH_(3)(NH_(3)-SCR)in the presence of CH_(2)Cl_(2).Commercial V_(2)O_(5)-WO_(3)-TiO_(2) catalyst was also prepared for comparison.The physcial properties and chemical properties of the Nb_(2)O_(5) loaded cerium nanotubes catalysts were investigated by X-ray diffractometer,Transmission electron microscope,Brunauer-Emmett-Teller specific surface area,H_(2)-temperature programmed reduction,NH_(3)-temperature programmed desorption and Xray photoelectron spectroscopy.The experiment results showed that the loading amount of Nb_(2)O_(5) had a significant effect on the catalytic performance of the catalysts.10 wt.%Nb-Ce NTs catalyst presented the best NH_(3)-SCR performance and degradation efficiency of CH_(2)Cl_(2) among the prepared catalysts,due to its superior redox capability,abundant surface oxygen species and acid sites,the interaction between Nb and Ce,higher ratio of Nb^(4+)/(Nb^(5+)+Nb^(4+))and Ce^(3+)/(Ce^(3+)+Ce^(4+)),as well as the special tubular structure of cerium nanotube.This study may provide a practical approach for the design and synthesis of SCR catalysts for the simultaneously removal NOxand chlorinated volatile organic compounds(CVOCs)emitted from the stationary industrial sources.展开更多
Catalysts using α-FeOOH nanoparticles as the active ingredient were testedby a microreactor-chromatography assessing apparatus at atmospheric pressure between 25 and 60 ℃with a gas hourly space velocity of 10,000 h^...Catalysts using α-FeOOH nanoparticles as the active ingredient were testedby a microreactor-chromatography assessing apparatus at atmospheric pressure between 25 and 60 ℃with a gas hourly space velocity of 10,000 h^(-1), while the removal performance of H_2S withcatalysts was investigated using the thermal gravimetric method. The results show that the catalystsare highly active for COS hydrolysis at low temperatures (≤60 ℃) and high gas hourly spacevelocity, and the highest activity can reach 100%. The catalyst is particularly stable for 12 h, andno deactivation is observed. Nanoparticle α-FeOOH prepared using hydrated iron sulfate showshigher COS hydrolysis activity, and the optimum calcination temperature for the catalyst is 260 ℃.In addition, the catalysts can remove COS and H_2S simultaneously, and 60 ℃ is favorable for theremoval of H_2S. The compensation effect exists in nanoparticle-based catalysts.展开更多
V-Pd/γ-Al2O3-TiO2 catalysts with different vanadium contents were prepared by a combined sol-gel and impregnation method. X-ray diffraction （XRD）, N2 adsorption-desorption （BET）, X-ray photoelectron spectroscopy ...V-Pd/γ-Al2O3-TiO2 catalysts with different vanadium contents were prepared by a combined sol-gel and impregnation method. X-ray diffraction （XRD）, N2 adsorption-desorption （BET）, X-ray photoelectron spectroscopy （XPS） and catalytic removal of ethanol, acetaldehyde and nitrogen oxides at low temperature （〈300 ？C） were used to assess the properties of the catalysts. The results showed that the sample with 1wt% vanadium exhibited an excellent catalytic performance for simultaneous removal of ethanol, acetaldehyde and nitrogen oxides. The conversions of ethanol, acetaldehyde and nitrogen oxides at 250 ？C were 100%, 74.4% and 98.7%, respectively. V-Pd/γ-Al2O3-TiO2 catalyst with 1 wt% vanadium showed the largest surface area and higher dispersion of vanadium oxide on the catalyst surface, and possessed a larger mole fraction of V4＋ species and unique PdO species on the surface, which can be attributed to the strong synergistic effect among palladium, vanadium and the carriers. The higher activity of V-Pd/γ-Al2O3-TiO2 catalyst is related to the V4＋ and Pd2＋ species on the surface, which might be favorable for the formation of active sites.展开更多
The activities of ZrO_2-supported precious metal catalysts for simultaneous removal of soot and NO_x in the presence of rich O_2and H_2O as well as SO_2 have been studied by keeping loose contact between catalyst and ...The activities of ZrO_2-supported precious metal catalysts for simultaneous removal of soot and NO_x in the presence of rich O_2and H_2O as well as SO_2 have been studied by keeping loose contact between catalyst and soot.The results show that only Ru,Ir and Rh have catalytic activity for simultaneous removal of soot and NO_x and the order of catalytic activity is Ru > Ir > Rh.Pt has the catalytic activity only for the removal of soot,and Ag,Pd,and Au have hardly any catalytic activities for the removal of soot and NO_x.The relationships between catalytic activity of precious metal catalysts and various reaction conditions were discussed.展开更多
Diesel engine exhaust comprises nitrogen oxides(NOx)and soot particles,which cause serious air pollution.However,owing to the contradictory nature of NO_(x)reduction and soot oxidation,a trade-off exists in the simult...Diesel engine exhaust comprises nitrogen oxides(NOx)and soot particles,which cause serious air pollution.However,owing to the contradictory nature of NO_(x)reduction and soot oxidation,a trade-off exists in the simultaneous removal of NO_(x)and soot.Consequently,catalytic technology has become a hot research topic.This study prepared MOδ/Fe-Beta(M=Fe,Co,Ni,Mn,Cu)catalysts through incipient wetness impregnation using Fe-Beta as the support and explored the catalytic performance of the above catalysts.The results exhibited the good performance of the prepared catalysts.The introduction of Mn resulted in a lower peak temperature of soot combustion for the catalyst,and slightly decreased deNOx performance of Fe-Beta.The soot combustion temperature was as low as 422℃,and the temperature window for 80%NO conversion was 164-423℃.The interaction between MnOd and zeolite can regulate the acid sites and produce sufficient active oxygen species for the catalyst.The catalytic activity of the MnOδ/Fe-Beta catalyst is due to its strong redox property,the appropriate number of acid sites,and sufficient number of active oxygen species.In addition,the catalyst had good stability and water and sulfur resistance,therefore it had great potential for future application in the simultaneous removal of NO_(x)and soot from diesel engine exhaust.展开更多
Layered manganese dioxide(δ-MnO_(2))is considered a promising ammonium ion capture electrode material for capacitive deionization(CDI)attributed to its high theoretical capacity and cost-effectiveness.Nevertheless,it...Layered manganese dioxide(δ-MnO_(2))is considered a promising ammonium ion capture electrode material for capacitive deionization(CDI)attributed to its high theoretical capacity and cost-effectiveness.Nevertheless,it continues to encounter challenges including rapid capacity degradation,structural instability,and Jahn-Teller effect.Herein,a crystal and electron synergistically regulation engineering strategy is proposed for the suppression of the Jahn-Teller effect and the improvement of ammonium ion storage dynamics in F doped MnO_(2)(MnOF).The induced action of F ions transforms the MnO_(2)structure from the original cubic[MnO_(6)]octahedron into an asymmetric[Mn(OF)_(6)]octahedron with electron redistribution,and generates a localized charge imbalance along the O-Mn-F pathway,which promotes electron transfer from Mn to F direction,accelerates electron transfer,and reduces the energy barrier of ammonium ion diffusion.As a result,the prepared MnOF exhibited a maximum salt adsorption capacity of 144.3 mg g^(−1)and an exceptionally high salt adsorption rate of 18.25 mg g^(−1)min^(-1),along with outstanding cycling stability.Besides,ex/in situ characterizations reveal that in MnOF,the formation/breaking of hydrogen bond is accompanied by the insertion/deinsertion of NH_(4)^(+).Therefore,the rational introduction of highly electronegative anions provides a new direction for the development of advanced CDI electrode materials.展开更多
MnO2-10aded D301 weak basic anion exchange resin has been used as adsorbent to simultaneously remove lead and cadmium ions from aqueous solution.The effects of adsorbent dosage,solution pH and the coexistent ions on t...MnO2-10aded D301 weak basic anion exchange resin has been used as adsorbent to simultaneously remove lead and cadmium ions from aqueous solution.The effects of adsorbent dosage,solution pH and the coexistent ions on the adsorption were investigated.Experimental results showed that with the adsorbent dosage more than 0.6 g/L,both Pb^2+and Cd^2+were simultaneously removed at pH range 5-6.Except for HPO4^2-,the high concentration coexistent ions such as Na^+,K^+,Cl^-,NO3^-,SO4^2-and HCO3^-,showed no significant effect on the removal efficiency of both Pb^2+and Cd^2+under the experimental conditions.The coexistence of Mg^2+,Ca^2+caused the reduction of Cd^2+removal,but not for Pb^2+.The adsorption equilibrium for Pb^2+and Cd^2+could be excellently described by the Langmuir isotherm model with R^2〉0.99.The maximum adsorption capacity was calculated as 80.64 mg/g for Pb^2+and 21.45 mg/g for Cd^2+.The adsorption processes followed the pseudo first-order kinetics model.MnO2-loaded D301 resin has been shown to have a potential to be used as an effective adsorbent for simultaneous removal of lead and cadmium ions from aqueous solution.展开更多
文摘In this paper,the recent progress of simultaneous removal of SO_2 and NO_x process at home and abroad is reviewed.We mainly introduced calcium based absorbent catalytic oxidation method,complexation absorption process,Electron beam method et al,principle of each technology are described,and the development direction was put forward in the future.
基金supported by Major Scientific and Technological Innovation Project of Shandong Province(No.2020CXGC011204)Qingdao Natural Science Foundation(No.23-2-1-234-zyyd-jch).
文摘The coexistence of emerging containments,such as antibiotic resistant bacteria(ARB),antibiotic-resistant genes(ARGs)and antibiotics,potentially influence elimination efficiencies in UV light-emitting diode(UV-LED)alone and UV-LED/H_(2)O_(2) system as their complex interactions.Tetracycline(TC)degradation efficiency(kF)correlated closely with its UV molar absorbance(R^(2)=0.831)in UV-LED alone system and with·OH yield(R^(2)=0.999)in UV-LED/H_(2)O_(2) system across studied wavelengths(265,280 and 310 nm).The kF values for intracellular DNA(i-ARGs)also exhibited a high correlation with UV-LED wavelengths in both systems(R^(2)=0.997-0.999).The coexistence of TC and ARB/ARGs resulted in a mutual inhibition of their degradation efficiencies due to competition for photons and·OH,along with the consequent reduction in intracellular ROS within ARB,with their degradation efficiencies exhibiting marked dependence on wavelength in both systems.Notably,the UV-LED/H_(2)O_(2) system at 265 nm effectively achieved the simultaneous removal of TC,ARB and ARGs with minimal energy consumption,and successfully fragmented ARGs.The degradation pathway of TC was analyzed,and the biotoxicity of its degradation intermediates demonstrated the environmental friendliness and safety of UV-LED/H_(2)O_(2) technology.This study elucidated the competitive interactions between antibiotics and ARB/ARGs within UV-LED/H_(2)O_(2) system,providing a promising approach for their simultaneous removal while ensuring energy efficiency.
基金Supported by the National Natural Science Foundation of China(21536009)Science and Technology Plan Projects of Shaanxi Province(2017ZDCXL-GY-10-03)
文摘Nitric oxide （NO） removal and sulfur dioxide （SO2） removal by sodium persulfate （Na2S2O8） were studied in a Bubble Column Reactor. The proposed reaction pathways of NO and SO2 removal are discussed. The effects of temperatures （35-90℃）, Na25208 （0.05-0.5 mol·L-1）, FeSO4 （0.5-5.0 m mol·L-1） and H2O2 （0.25 mol·L-1） on NO and SO2 removal were investigated. The results indicated that increased persulfate concentration led to increase in NO removal at various temperatures. SO2 was almost completely removed in the temperature range of 55-85 ℃. Fe2 ＋ accelerated persulfate activation and enhanced NO removal efficiency. At 0.2 mol· L- 1 Na2S2O8 and 0.5-1.0 mmol· L-1Fe2 ＋, NO removal of 93.5%-99% was obtained at 75-90 ℃, SO2 removal was higher than 99% at all temperatures. The addition of 0.25 mol. L i H202 into 0.2 mol·L-1· Na2S2O8 solution promoted NO removal efficiency apparently until utterly decomposition of H2O2, the SO2 removal was as high as 98.4% separately at 35 ℃ and 80 ℃.
基金Project supported by the National Natural Science Foundation of China(62175266,61775245)。
文摘The removal of harmful cyanobacterial blooms(HCBs)and reuse of the resulting algal sludge are pressing issues in current environmental governance and ecological conservation.Aiming at tackling the abovementioned challenges,titanium(Ti)-based coagulants are promising candidates.However,most of them suffer from poor stability and weak actual algal removal ability,and recycling of the algal sludge usually produces titanium dioxide(TiO_(2))with low photocatalytic ability.In this work,a lanthanum(La)-modified polytitanium chloride(La-PTC)coagulant is reported.La in the La-PTC coagulant serves a"kill two birds with one stone"strategy in algae removal and algae sludge reuse.Owing to the introduction of La ions,the La-PTC coagulant exhibits ultra-high stability and excellent algae removal capability with an efficiency of 98.71%,which is 7.25%higher than that of PTC coagulant.Moreover,recycling algae sludge can prepare high catalytic(2.45 times the commercial P25 TiO_(2))La/C-TiO_(2),where the presence of La enhances its visible light response range and inhibits electron hole recombination.The strategy of this La modified coagulant can not only achieve efficient re moval of HCBs,but also transfo rm the recovered algal sludge into photocatalysts with higher catalytic capacity.
基金financially supported by the Natural Science Foundation of ShanDong(Nos.ZR2023QD152 and ZR2021MD002).
文摘The application of photocatalytic technology in algae killing is limited by the non-floatability and difficulty in recycling of the photocatalysts.Loading photocatalyst on magnetic or floatable carriers is the most popular method for overcoming the above inadequacies.In this work,a CdZnS/TiO_(2) membrane photocatalyst with adjustable suspended depth(include floating)and flexible assembly is designed,which is less prone to dislodgement due to in situ synthesis and has a wider range of applicability than previously reported photocatalysts.The photocatalytic removal of Microcystis aeruginosa revealed that the suspended depth and distribution format of the CdZnS/TiO_(2) membrane photocatalysts have striking effects on the photocatalytic removal performance of Microcystis aeruginosa,the photocatalytic removal efficiency of CdZnS/TiO_(2)-2 membrane photocatalysts for Microcystis aeruginosa could reach to 98.6%in 60 min when the photocatalysts assembled in the form of 3×3 arrays suspended at a depth of 2 cm from the liquid surface.A tiny amount of TiO_(2) loading allows the formation of Z-Scheme heterojunction,resulting in accelerating the separation efficiency of photogenerated carriers,preserving the photogenerated electrons and holes with stronger reduction and oxidation ability and inhabiting the photo-corrosion of CdZnS.
基金supported by the National Key Research and Development Program of China(No.2021YFC3201505-02)Shenzhen Science and Technology Plan Collaborative Innovation Project-Undertake Major National Science and Technology Projects of China(No.CJGJZD2020061710260200).
文摘Heterotrophic denitrification based on polylactic acid(PLAHD)can remove nitrate effectively,but it is expensive and can't remove phosphate.Autotrophic denitrification based on iron sulfide(ISAD)can simultaneously remove nitrate and phosphate cost-effectively,but its nitrate rate is slow.So,iron sulfide mineral/polylactic acid mixotrophic biofilter(ISPLAB)was constructed to combine advantages of ISAD and PLAHD.ISPLAB achieved nitrogen and phosphorus removal rates of 98.04%and 94.12%,respectively,at a hydraulic retention time(HRT)of 24 h.The study also revealed that controlling molecular weight(MW)of PLA improved the release of soluble organic matter;adding iron sulfide enhanced the hydrolysis of PLA and precipitated PO_(4)^(3-) of Fe^(2+)/Fe^(3+),thereby facilitated simultaneous nitrogen and phosphorus removal.Microbial community analysis resulted that denitrifying bacterias(Phaeodactylibacter and Methylotenera),sulfur-reducing bacterias(Hyphomicrobium),sulfur-oxidizing bacteria(Denitratisoma),iron-reducing bacteria(Romboutsia)and hydrolyzed bacterias(norank_f_norank_o_1-20 and norank_f_Caldilineaceae)coexisted in the ISPLAB system.Organics and iron sulfide drived the denitrification process in ISPLAB.
基金National Key Research and Development Program of China(Nos.2023YFD1702003 and 2023YFC3709001).
文摘This study aims to optimize the use of lacquer residue biomass(LBM).We investigated the ability of LBM to remove Pb^(2+)heavy metal ions and the typical cationic dye methylene blue(MB)and anionic dye Congo red(CR)by simultaneous adsorption from composite systems,as well as the relevant factors.Scanning electron microscopy(SEM),X-ray diffraction(XRD),and Fourier transform infrared spectroscopy(FTIR)were used to characterize adsorption behavior.The adsorption kinetics of Pb^(2+)-MB/CR composite systems can be effectively characterized by the pseudo-second-order kinetic model(R^(2)>0.97).In the Pb^(2+)-MB composite system,adsorption was antagonistic with similar adsorption sites.However,in the Pb^(2+)-CR composite system,we found that adsorption was synergistic with different adsorption sites,which led to a higher simultaneous adsorption capacity for a higher initial Pb^(2+)-CR concentration,unlike the Pb^(2+)-MB system.In both composite systems,an appropriate increase in LBM dosage and system temperature within a certain range was conducive to simultaneous adsorption and removal of Pb^(2+)-MB/CR composite systems.The optimal solid-liquid ratio and temperature were 1:75 and 30℃,respectively.The adsorption and removal rates of Pb^(2+)and MB were 99.98%and 90.49%,respectively,and those of Pb^(2+)and CR were 93.99%and 77.39%,respectively,in(50,50)mg/L of Pb^(2+)-MB/CR composite systems under these conditions.Adsorption removal of Pb^(2+)and MB improved with higher pH levels,and worsened with the increase of ionic strength in the solution,while the removal rate of CR showed an opposite trend.The coexisting anion and cation types had limited influence on the simultaneous adsorption removal of Pb^(2+),MB,and CR.The results of desorption showed that LBM can be utilized as a disposable material for simultaneously treating Pb^(2+)-MB/CR composite systems.The simultaneous adsorption mechanisms of Pb^(2+)-MB/CR mainly involved hydrogen bonding,π-πbonding interaction,and electrostatic interaction.
基金supported by the National Natural Science Foundation of China(52404258)Postdoctoral Fellowship Program of CPSF(GZB20230714)+1 种基金Anhui Provincial Natural Science Foundation(2408085QE173)China Postdoctoral Science Foundation funded project(2023M743387)。
文摘Two-dimensional black phosphorus(2D BP)utilized in flame retardant applications frequently encounters significant challenges,including inadequate ambient stability and elevated carbon monoxide(CO)release rates.To mitigate these issues,an effective approach was proposed for the fabrication of 2D heterostructures comprising copper oxide intercalated with BP in this work.This methodology takes into account both thermodynamic and kinetic factors,resulting in substantial enhancements in the ambient stability of BP and the catalytic performance for CO elimination,achieved through the synergistic interactions between 2D BP and copper oxide,all while preserving the structural integrity of 2D BP.The incorporation of gelatin and kosmotropic anions facilitated the efficient adhesion of the multifunctional heterostructures to the flammable flexible polyurethane foam(FPUF),which not only scavenged free radicals in the gas phase but also catalyzed the formation of a dense carbon layer in the condensed phase.Kosmotropic anions induce a salting-out effect that fosters the development of a chain bundle,a hydrophobic interaction domain,and a potential microphase separation region within the gelatin chains,leading to a marked improvement in the mechanical strength of the heterostructure coatings.The modified FPUF exhibited a high limiting oxygen index(LOI)value of 34%,alongside significantly improved flame resistance:the peak CO release rate was reduced by 78%,the peak heat release rate decreased by 57%,and the fire performance index(FPI)was increased by 40 times compared to untreated FPUF.The 2D heterostructure coatings demonstrated better CO catalytic removal performance relative to previously reported flame retardant products.This research offers a promising design principle for the development of next-generation high-performance flame retardant coatings aimed at enhancing fire protection.
基金Project supported by the National Natural Science Foundation of China(21501097,21272118,21577065)the Natural Science Foundation of Jiangsu Province(BK20170954)+2 种基金the Startup Foundation for Introducing Talent of NUIST(2017r073)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China,China(18KJB430019)University Science Research Project of Jiangsu Province(18KJB430019)
文摘The Mn-Ce-Nb-O_x/P84 catalytic filter for removal of particulates and NO simultaneous was prepared by a novel method(foam coating method). The process parameters including the concentrations of PTFE emulsion, particle size of catalyst and calcination temperature for preparation of catalytic filters were analyzed. In addition, the physical properties and performance for removal of NO(NH_3-SCR) and particulates of Mn-Ce-Nb-O_x/P84 catalytic filter prepared under the optimized parameters, were also systematic studied. Results show that the process parameters had significant influences on stability and performance of catalytic filter, The Mn-Ce-Nb-O_x/P84 catalytic filter prepared by foam coating method under the optimized parameters, has satisfactory physical properties and catalytic performance for removal of NO and particulates at 140-220 ℃. The NO removal efficiency of catalytic filter can reach95.3% at 200 ℃ as the catalyst loading amount is 450 g/m^2, Moreover,the dust removal efficiency of MnGe-Nb-O_x/P84 catalytic filter reaches as high as 99.98%, and the PM2.5 removal efficiency also reaches99.98%. The anti-sulfur performance of Mn-Ce-Nb-O_x catalytic filter is also attractive, after injecting150 ppm SO_2, the NO removal efficiency still retains up to 85%. It is indicated that the foam coating method can not only make a bond of high strength between catalyst and filter, but also make the catalytic filter possessing an excellent and stable performance for removal of NO and particulates.
基金supported by the National Natural Science Foundation of China (51778084)the National key Research&Development program of China (2018YFC1800305)+2 种基金the Chongqing Ecology and Environment Bureau (2019-128)the Sichuan Science and Technology Program (2019YFSY0005)the Large Instruments Open Foundation of Chongqing University (201903150051)。
文摘Cadmium(Cd),lead(Pb),and hexavalent chromium(Cr(Ⅵ)) are often found in soils and water affected by metal smelting,chemical manufacturing,and electroplating.In this study,synthetic iron sulfide nanoparticles(FeS NPs) were stabilized with carboxymethyl cellulose(CMC) and utilized to remove Cr(Ⅵ),Cd,and Pb from an aqueous solution.Batch experiments,a Visual MINTEQ model,scanning electron microscopy(SEM),X-ray diffraction(XRD),and X-ray photoelectron spectrometer(XPS) analysis were used to determine the removal efficiencies,influencing factors,and mechanisms.The FeS NP suspension simultaneously removed Cr(Ⅵ),Cd,and Pb from an aqueous solution.The concentrations of Cr(Ⅵ),Cd,and Pb decreased from 50,10,and 50 mg·L^(-1) to 2.5,0.1,and 0.1 mg·L^(-1),respectively.The removal capacities were up to 418,96,and 585 mg per gram of stabilized FeS NPs,respectively.The acidic conditions significantly favored the removal of aqueous Cr(Ⅵ) while the alkaline conditions favored the removal of Cd and Pb.Oxygen slightly inhibited the removal of Cr(Ⅵ),but it had no significant influence on the removal of Cd and Pb.A potential mechanism was proposed for the simultaneous removal of Cr(Ⅵ),Cd,and Pb using FeS NPs.The interactions of the three heavy metals involved a cationic bridging effect on Cr(Ⅵ) by Cd,an enhanced adsorption effect on Cd by [Cr,Fe](OH)_3,precipitation of PbCrO_4,and transformation of PbCrO_4 to PbS.Therefore,FeS NPs have a high potential for use in the simultaneous removal of Cr(Ⅵ),Cd,and Pb from contaminated aqueous solutions.
基金supported by the National Natural Science Foundation of China(Nos.52000093,51968034,41807373 and21667015)National Key R&D Program of China(No.2018YFC0213400)+1 种基金China Postdoctoral Science Foundation(Nos.2020T130271,2019M663911XB)Open Fund of National Engineering Laboratory for Mobile Source Emission Control Technology(No.NELMS2019B03)。
文摘The simultaneous removal of SO_(2),NO_(x)and Hg^(0)from industrial exhaust flue gas has drawn worldwide attention in recent years.A particularly attractive technique is selective catalytic reduction,which effectively removes SO_(2),NO_(x)and Hg^(0)at low temperatures.This paper first reviews the simultaneous removal of SO_(2),NO_(x)and Hg^(0)by unsupported and supported catalysts.It then describes and compares the research progress of various carriers,eg.,carbon-based materials,metal oxides,silica,molecular sieves,metal-organic frameworks,and pillared interlayered clays,in the simultaneous removal of SO_(2),NO_(x)and Hg^(0).The effects of flue-gas components(such as O_(2),NH3,HCl,H2 O,SO_(2),NO and Hg^(0))on the removal of SO_(2),NOx,and Hg^(0)are discussed comprehensively and systematically.After summarizing the pollutantremoval mechanism,the review discusses future developments in the simultaneous removal of SO_(2),NOx and Hg^(0)by catalysts.
基金Project supported by the National Natural Sciences Foundation of China(No.50576037)Natural Science Foundation of Jiangsu Province(No.BK2006198)
文摘In order to investigate the feasibility of sequential removal NO and SO2 using non-thermal plasma and adsorbent simultaneously, the removal of NO and SO2 from dry gas stream （NO/SO2/N2/O2） with very little O2 using non-thermal plasma was investigated using a coaxial dielectric barrier discharge. Comparative experiments were carried out in the dry gas stream with and without Ar respectively at O2 concentration of 0.1%. The results showed that NO could be removed remarkably and it would be enhanced in the presence of Ar in the dry gas stream. It seems that SO2 could not be removed unless there is Ar in the dry gas stream. The mechanism of removal of NO and SO2 in the dry gas stream was discussed.
文摘The simultaneous removal of NOx and particulate matter(PM) from diesel exhaust is investigated over a mixed metal oxide catalyst of La 0.9 K 0.1 CoO 3 loaded on γ-Al 2O 3 spherules with the assistant of plasma. It was found that NOx was reduced by PM in oxygen rich atmosphere, the CO 2 and N 2 were produced in the same temperature window without considering the N 2 formed by plasma decomposition. As a result, the temperature for the PM combustion decreases and the reduction efficiency of NOx to N 2 increases during the plasma process, which indicated that the activity of the catalyst can be improved by plasma. The NOx is decomposed by plasma at both low temperature and high temperature. Therefore, the whole efficiency of NOx conversion is enhanced.
基金financially supported by National Natural Science Foundation of China(Nos.52070168 and 51708492)National Key Research and Development Plan of China(No.2016YFC0204100)+1 种基金Zhejiang Provincial“151 Talents Programthe Program for Zhejiang Leading Team of S&T Innovation(No.2013TD07)。
文摘Herein,a series of niobium oxide supported cerium nanotubes(Ce NTs)catalysts with different loading amount of Nb_(2)O_(5)(0–10 wt.%)were prepared and used for selective catalytic reduction of NOxwith NH_(3)(NH_(3)-SCR)in the presence of CH_(2)Cl_(2).Commercial V_(2)O_(5)-WO_(3)-TiO_(2) catalyst was also prepared for comparison.The physcial properties and chemical properties of the Nb_(2)O_(5) loaded cerium nanotubes catalysts were investigated by X-ray diffractometer,Transmission electron microscope,Brunauer-Emmett-Teller specific surface area,H_(2)-temperature programmed reduction,NH_(3)-temperature programmed desorption and Xray photoelectron spectroscopy.The experiment results showed that the loading amount of Nb_(2)O_(5) had a significant effect on the catalytic performance of the catalysts.10 wt.%Nb-Ce NTs catalyst presented the best NH_(3)-SCR performance and degradation efficiency of CH_(2)Cl_(2) among the prepared catalysts,due to its superior redox capability,abundant surface oxygen species and acid sites,the interaction between Nb and Ce,higher ratio of Nb^(4+)/(Nb^(5+)+Nb^(4+))and Ce^(3+)/(Ce^(3+)+Ce^(4+)),as well as the special tubular structure of cerium nanotube.This study may provide a practical approach for the design and synthesis of SCR catalysts for the simultaneously removal NOxand chlorinated volatile organic compounds(CVOCs)emitted from the stationary industrial sources.
文摘Catalysts using α-FeOOH nanoparticles as the active ingredient were testedby a microreactor-chromatography assessing apparatus at atmospheric pressure between 25 and 60 ℃with a gas hourly space velocity of 10,000 h^(-1), while the removal performance of H_2S withcatalysts was investigated using the thermal gravimetric method. The results show that the catalystsare highly active for COS hydrolysis at low temperatures (≤60 ℃) and high gas hourly spacevelocity, and the highest activity can reach 100%. The catalyst is particularly stable for 12 h, andno deactivation is observed. Nanoparticle α-FeOOH prepared using hydrated iron sulfate showshigher COS hydrolysis activity, and the optimum calcination temperature for the catalyst is 260 ℃.In addition, the catalysts can remove COS and H_2S simultaneously, and 60 ℃ is favorable for theremoval of H_2S. The compensation effect exists in nanoparticle-based catalysts.
基金supported by the National Natural Science Foundation of China (No. 21073131)the Shanxi Natural Science Foundation(No. 2009011011-3)
文摘V-Pd/γ-Al2O3-TiO2 catalysts with different vanadium contents were prepared by a combined sol-gel and impregnation method. X-ray diffraction （XRD）, N2 adsorption-desorption （BET）, X-ray photoelectron spectroscopy （XPS） and catalytic removal of ethanol, acetaldehyde and nitrogen oxides at low temperature （〈300 ？C） were used to assess the properties of the catalysts. The results showed that the sample with 1wt% vanadium exhibited an excellent catalytic performance for simultaneous removal of ethanol, acetaldehyde and nitrogen oxides. The conversions of ethanol, acetaldehyde and nitrogen oxides at 250 ？C were 100%, 74.4% and 98.7%, respectively. V-Pd/γ-Al2O3-TiO2 catalyst with 1 wt% vanadium showed the largest surface area and higher dispersion of vanadium oxide on the catalyst surface, and possessed a larger mole fraction of V4＋ species and unique PdO species on the surface, which can be attributed to the strong synergistic effect among palladium, vanadium and the carriers. The higher activity of V-Pd/γ-Al2O3-TiO2 catalyst is related to the V4＋ and Pd2＋ species on the surface, which might be favorable for the formation of active sites.
基金the Special Fund for the Development of Strategic and New Industry in Shenzhen,China(No.JCYJ20130329162012793)National Natural Science Foundation for Young Scholars,China(Nos.20907012,ZYC201105160189A)the Basic Research Plan in Shenzhen City,China(No.JC201105160593A)
文摘The activities of ZrO_2-supported precious metal catalysts for simultaneous removal of soot and NO_x in the presence of rich O_2and H_2O as well as SO_2 have been studied by keeping loose contact between catalyst and soot.The results show that only Ru,Ir and Rh have catalytic activity for simultaneous removal of soot and NO_x and the order of catalytic activity is Ru > Ir > Rh.Pt has the catalytic activity only for the removal of soot,and Ag,Pd,and Au have hardly any catalytic activities for the removal of soot and NO_x.The relationships between catalytic activity of precious metal catalysts and various reaction conditions were discussed.
基金supported by National Natural Science Foundation of China(22372107,22072095,22202058)Postgraduate Education Reform Project of Liaoning Province(LNYJG2022400,LNYJG2023280)+3 种基金National Key Research and Development Program of China(2022YFB3506200,2022YFB3504100)Excellent Youth Science Foundation of Liaoning Province(2022-YQ-20)Shenyang Science and Technology Planning Project(22-322-3-28)Liaoning Xingliao talented youth Top talent program(XLYC2203007).
文摘Diesel engine exhaust comprises nitrogen oxides(NOx)and soot particles,which cause serious air pollution.However,owing to the contradictory nature of NO_(x)reduction and soot oxidation,a trade-off exists in the simultaneous removal of NO_(x)and soot.Consequently,catalytic technology has become a hot research topic.This study prepared MOδ/Fe-Beta(M=Fe,Co,Ni,Mn,Cu)catalysts through incipient wetness impregnation using Fe-Beta as the support and explored the catalytic performance of the above catalysts.The results exhibited the good performance of the prepared catalysts.The introduction of Mn resulted in a lower peak temperature of soot combustion for the catalyst,and slightly decreased deNOx performance of Fe-Beta.The soot combustion temperature was as low as 422℃,and the temperature window for 80%NO conversion was 164-423℃.The interaction between MnOd and zeolite can regulate the acid sites and produce sufficient active oxygen species for the catalyst.The catalytic activity of the MnOδ/Fe-Beta catalyst is due to its strong redox property,the appropriate number of acid sites,and sufficient number of active oxygen species.In addition,the catalyst had good stability and water and sulfur resistance,therefore it had great potential for future application in the simultaneous removal of NO_(x)and soot from diesel engine exhaust.
基金financial support from the National Natural Science Foundation of China(22108032 and 22178055)the Dongguan Introduction Program of Leading Innovative and Entrepreneurial Talents+1 种基金the support of characterization from the Dongguan University of Technology Analytical and Testing Centerthe Guangdong Provincial Key Laboratory of Intelligent Disaster Prevention and Emergency Technologies for Urban Lifeline Engineering(2022)(Grant No.2022B1212010016).
文摘Layered manganese dioxide(δ-MnO_(2))is considered a promising ammonium ion capture electrode material for capacitive deionization(CDI)attributed to its high theoretical capacity and cost-effectiveness.Nevertheless,it continues to encounter challenges including rapid capacity degradation,structural instability,and Jahn-Teller effect.Herein,a crystal and electron synergistically regulation engineering strategy is proposed for the suppression of the Jahn-Teller effect and the improvement of ammonium ion storage dynamics in F doped MnO_(2)(MnOF).The induced action of F ions transforms the MnO_(2)structure from the original cubic[MnO_(6)]octahedron into an asymmetric[Mn(OF)_(6)]octahedron with electron redistribution,and generates a localized charge imbalance along the O-Mn-F pathway,which promotes electron transfer from Mn to F direction,accelerates electron transfer,and reduces the energy barrier of ammonium ion diffusion.As a result,the prepared MnOF exhibited a maximum salt adsorption capacity of 144.3 mg g^(−1)and an exceptionally high salt adsorption rate of 18.25 mg g^(−1)min^(-1),along with outstanding cycling stability.Besides,ex/in situ characterizations reveal that in MnOF,the formation/breaking of hydrogen bond is accompanied by the insertion/deinsertion of NH_(4)^(+).Therefore,the rational introduction of highly electronegative anions provides a new direction for the development of advanced CDI electrode materials.
基金supported by the National Mega-Project of Science and Technology of China(No.2008ZX07421-002)the International Cooperation Project of Chinese Ministry of Science and Technology(No.2007DFR90050)
文摘MnO2-10aded D301 weak basic anion exchange resin has been used as adsorbent to simultaneously remove lead and cadmium ions from aqueous solution.The effects of adsorbent dosage,solution pH and the coexistent ions on the adsorption were investigated.Experimental results showed that with the adsorbent dosage more than 0.6 g/L,both Pb^2+and Cd^2+were simultaneously removed at pH range 5-6.Except for HPO4^2-,the high concentration coexistent ions such as Na^+,K^+,Cl^-,NO3^-,SO4^2-and HCO3^-,showed no significant effect on the removal efficiency of both Pb^2+and Cd^2+under the experimental conditions.The coexistence of Mg^2+,Ca^2+caused the reduction of Cd^2+removal,but not for Pb^2+.The adsorption equilibrium for Pb^2+and Cd^2+could be excellently described by the Langmuir isotherm model with R^2〉0.99.The maximum adsorption capacity was calculated as 80.64 mg/g for Pb^2+and 21.45 mg/g for Cd^2+.The adsorption processes followed the pseudo first-order kinetics model.MnO2-loaded D301 resin has been shown to have a potential to be used as an effective adsorbent for simultaneous removal of lead and cadmium ions from aqueous solution.
