Bentonite is a kind of natural clay with good exchanging ability. By exchanging its interlamellar cations with various soluble cations, such as quaternary ammonium cations and inorganic metal ions, the properties of n...Bentonite is a kind of natural clay with good exchanging ability. By exchanging its interlamellar cations with various soluble cations, such as quaternary ammonium cations and inorganic metal ions, the properties of natural bentonite can be greatly improved. In this study, hexadecyltrimethylammonium bromide (HDTMA), CaCl2, MgCl2, FeCl3, AlCl3 were used as organic and inorganic pillared materials respectively to produce several kinds of Ca-, Mg-, Fe-, Al-organo pillared bentonites. Sorption of reactive red X-3B on them was studied to determine their potential application as sorbents in wastewater treatment. The results showed that these pillared bentonites had much improved sorption properties, and that the dye solutions’ pH value had some effect on the performance of these inorgano-organo pillared bentonites. Isotherms of reactive X-3B on these pillared bentonites sug-gested a Langmuir-type sorption mechanism.展开更多
The oxidation of 200mg/l reactive red X-3B wastewater was studied by a combination of electrodeless ultraviolet lamp and hydrogen peroxide,hydrogen peroxide alone,microwave alone,electrodeless ultraviolet light（UV）-...The oxidation of 200mg/l reactive red X-3B wastewater was studied by a combination of electrodeless ultraviolet lamp and hydrogen peroxide,hydrogen peroxide alone,microwave alone,electrodeless ultraviolet light（UV）-radiation and microwave irradiation alone,respectively.the results showed that the different oxidation methods were that:MW/UV/H2O2>H2O2 alone>MW/UV>MW alone.when treating time was 60 min,The dye solution was decolored completely,and TOC removal was 52.95%.The mechanism of degradation was explored primarily by GC-MS analysis.展开更多
The（CeO2/C）-β-PbO2-PTFE composite electrodes modified by graphite powder,cerium oxide powder,polytetrafluoroethylene（PTFE）and the homemade β-PbO2 powder were prepared by the high pressure molding technique.The X...The（CeO2/C）-β-PbO2-PTFE composite electrodes modified by graphite powder,cerium oxide powder,polytetrafluoroethylene（PTFE）and the homemade β-PbO2 powder were prepared by the high pressure molding technique.The X-ray diffraction（XRD）was used to test the purity of the homemade β-PbO2 powder.The surface structure and electrical property of electrodes were characterized by using scanning electron microscopy（SEM）and the cyclic voltammetry curves（CV）.Those images indicated that in electrolysis the（CeO2/C）-β-PbO2-PTFE composite electrodes had higher activity than the β-PbO2-PTFE electrodes,as good as the excellent catalytic performance.In the electrode system the composite electrodes were applied to treat reactive brilliant red（RBR）X-3B solution and we studied the degradation influence factors and the reaction mechanism.The results showed that the electrode system was well in treating RBR X-3B solution with the 20%（CeO2/C）-β-PbO2-PTFE composite electrodes at the initial 100 mg/L RBR X-3B concentration,Na2SO4 concentration of 0.35 mol/L,the constant current density of 30 mA/cm~!2 and electrolyte pH =2.After electrolytic time of 90 min,the maximum decolorization and chemical oxygen demand（COD）removal rates reached 88.92% and 54.54%.And the decolorization rate of RBR X-3B was in conformity with pseudo-first-order kinetics equation.The RBR X-3B degradation mechanism in the electrochemical oxidation system was used with LC-MS to analyze the possible intermediates and degradation pathway.展开更多
Catalytic ozonation of Reactive Red X-3B in aqueous solution had been carried out in an ozone oxidation reactor where Mn-Fe-ceramic honeycomb was used as the catalysts. The presence of Mn-Fe-ceramic honeycomb catalyst...Catalytic ozonation of Reactive Red X-3B in aqueous solution had been carried out in an ozone oxidation reactor where Mn-Fe-ceramic honeycomb was used as the catalysts. The presence of Mn-Fe-ceramic honeycomb catalyst could obviously improve the deco- loration efficiency of Reactive Red X-3B and the utilization efficiency of ozone compared to the results from non-catalytic ozonation. Adsorption of Reactive Red X-3B had no obviously influence on the degradation efficiency. Addition of tert-butanol significantly decreased the degradation efficiency, indicating that the degradation of Reactive Red X-3B followed the mechanism of hydroxyl radical （OH.） oxidation. The operating variables such as reaction pressure and ozone supply had a positive influence on the degradation efficiency, mainly attributing to facilitate the ozone decomposition and OH. formation.展开更多
A novel polycyclodextrin-modified magnetic cationic hydrogel(PCD-MCH) was developed and its performance,kinetics and mechanism for the removal of reactive brilliant red X-3B(X-3B) were studied.The results showed that ...A novel polycyclodextrin-modified magnetic cationic hydrogel(PCD-MCH) was developed and its performance,kinetics and mechanism for the removal of reactive brilliant red X-3B(X-3B) were studied.The results showed that the zeta-potential of PCD-MCH was 32.8 to16.7 mV at pH 3.0-10.5.The maximum X-3B adsorption capacity of PCD-MCH was2792.3 mg/g.The adsorption kinetics could be well-described by the Weber-Morris model and the homogeneous surface diffusion model(HSDM).Diffusion stages corresponding to surface or film diffusion,intra-particle or wide mesopore diffusion,and narrow mesopore/micropore diffusion occurred at 0-120,120-480 and 480-1200 min,respectively.The latter two diffusion stages were rate-controlling for X-3B adsorption kinetics.At the initial X-3B concentration of 600 mg/L,the diffusion coefficient(Ds) and external mass transfer coefficient in the liquid phase(kF) were 3x10^-11 cm^2/min and 4.68 x 10^-6 cm/min,respectively.X-3B approaching the center of PCD-MCH particles could be observed at 360 min.At the end of the third diffusion stage,the Cp at q/qe=0 was 45.20 mg/L,which was close to the homogeneous Cp value of 46 mg/L along the radius of PCD-MCH particles.At pH 3.0-10.0,PCD-MCH showed stable X-3B adsorption capacities.After five regeneration-reuse cycles,the residual adsorption capacity of regenerated PCD-MCH was higher than 892.7 mg/g.The corresponding adsorption mechanism was identified as involving electrostatic interactions,cyclodextrin cavities and hydrogen bonds,of which cyclodextrin cavities showed prominent capture performance towards dye molecules through the formation of inclusion complexes.展开更多
The objective of this study was to prepare a new photocatalyst with high activities for degradation of organic pollutants.Coupled ZrO_(2)/ZnO photocatalyst was prepared with a simple precipitation method with cheap ra...The objective of this study was to prepare a new photocatalyst with high activities for degradation of organic pollutants.Coupled ZrO_(2)/ZnO photocatalyst was prepared with a simple precipitation method with cheap raw materials zinc acetate and zirconium oxychloride,and was character-ized by X-ray diffraction(XRD)and transmission electron microscopy(TEM).Reactive brilliant red X-3B was used as a model compound to investigate the photocatalytic activity of synthesized catalysts in water under 254 nm UV irradia-tion.Results show that the optimal calcination temperature and coupling molar ratio of Zr were 350°C and 2.5%,respec-tively.At the calcination temperature of 350°C,ZrO_(2) was dispersed on the surface of hexagonal ZnO in the form of amorphous clusters.The particle size of ZrO_(2)/ZnO decreased with the decrease of calcination temperature and the increase of Zr coupling amount.ZrO_(2)/ZnO has better photocatalytic activity for degradation of reactive brilliant red(RBR)X-3B than pure ZnO and P25-TiO_(2).展开更多
基金Project supported by the Scientific Research Foundation for Re-turned Overseas Scholars and the National Natural Science Founda-tion of China (No. 40576080)
文摘Bentonite is a kind of natural clay with good exchanging ability. By exchanging its interlamellar cations with various soluble cations, such as quaternary ammonium cations and inorganic metal ions, the properties of natural bentonite can be greatly improved. In this study, hexadecyltrimethylammonium bromide (HDTMA), CaCl2, MgCl2, FeCl3, AlCl3 were used as organic and inorganic pillared materials respectively to produce several kinds of Ca-, Mg-, Fe-, Al-organo pillared bentonites. Sorption of reactive red X-3B on them was studied to determine their potential application as sorbents in wastewater treatment. The results showed that these pillared bentonites had much improved sorption properties, and that the dye solutions’ pH value had some effect on the performance of these inorgano-organo pillared bentonites. Isotherms of reactive X-3B on these pillared bentonites sug-gested a Langmuir-type sorption mechanism.
文摘The oxidation of 200mg/l reactive red X-3B wastewater was studied by a combination of electrodeless ultraviolet lamp and hydrogen peroxide,hydrogen peroxide alone,microwave alone,electrodeless ultraviolet light（UV）-radiation and microwave irradiation alone,respectively.the results showed that the different oxidation methods were that:MW/UV/H2O2>H2O2 alone>MW/UV>MW alone.when treating time was 60 min,The dye solution was decolored completely,and TOC removal was 52.95%.The mechanism of degradation was explored primarily by GC-MS analysis.
基金Project supported by the Capacity Building Program of Shanghai Local Universities(12160503600)
文摘The（CeO2/C）-β-PbO2-PTFE composite electrodes modified by graphite powder,cerium oxide powder,polytetrafluoroethylene（PTFE）and the homemade β-PbO2 powder were prepared by the high pressure molding technique.The X-ray diffraction（XRD）was used to test the purity of the homemade β-PbO2 powder.The surface structure and electrical property of electrodes were characterized by using scanning electron microscopy（SEM）and the cyclic voltammetry curves（CV）.Those images indicated that in electrolysis the（CeO2/C）-β-PbO2-PTFE composite electrodes had higher activity than the β-PbO2-PTFE electrodes,as good as the excellent catalytic performance.In the electrode system the composite electrodes were applied to treat reactive brilliant red（RBR）X-3B solution and we studied the degradation influence factors and the reaction mechanism.The results showed that the electrode system was well in treating RBR X-3B solution with the 20%（CeO2/C）-β-PbO2-PTFE composite electrodes at the initial 100 mg/L RBR X-3B concentration,Na2SO4 concentration of 0.35 mol/L,the constant current density of 30 mA/cm~!2 and electrolyte pH =2.After electrolytic time of 90 min,the maximum decolorization and chemical oxygen demand（COD）removal rates reached 88.92% and 54.54%.And the decolorization rate of RBR X-3B was in conformity with pseudo-first-order kinetics equation.The RBR X-3B degradation mechanism in the electrochemical oxidation system was used with LC-MS to analyze the possible intermediates and degradation pathway.
文摘Catalytic ozonation of Reactive Red X-3B in aqueous solution had been carried out in an ozone oxidation reactor where Mn-Fe-ceramic honeycomb was used as the catalysts. The presence of Mn-Fe-ceramic honeycomb catalyst could obviously improve the deco- loration efficiency of Reactive Red X-3B and the utilization efficiency of ozone compared to the results from non-catalytic ozonation. Adsorption of Reactive Red X-3B had no obviously influence on the degradation efficiency. Addition of tert-butanol significantly decreased the degradation efficiency, indicating that the degradation of Reactive Red X-3B followed the mechanism of hydroxyl radical （OH.） oxidation. The operating variables such as reaction pressure and ozone supply had a positive influence on the degradation efficiency, mainly attributing to facilitate the ozone decomposition and OH. formation.
基金supported by the National Key Research and Development Program of China (No.2017YFC0505303)the National Natural Science Foundation of China (Nos.51478041 and 51678053).
文摘A novel polycyclodextrin-modified magnetic cationic hydrogel(PCD-MCH) was developed and its performance,kinetics and mechanism for the removal of reactive brilliant red X-3B(X-3B) were studied.The results showed that the zeta-potential of PCD-MCH was 32.8 to16.7 mV at pH 3.0-10.5.The maximum X-3B adsorption capacity of PCD-MCH was2792.3 mg/g.The adsorption kinetics could be well-described by the Weber-Morris model and the homogeneous surface diffusion model(HSDM).Diffusion stages corresponding to surface or film diffusion,intra-particle or wide mesopore diffusion,and narrow mesopore/micropore diffusion occurred at 0-120,120-480 and 480-1200 min,respectively.The latter two diffusion stages were rate-controlling for X-3B adsorption kinetics.At the initial X-3B concentration of 600 mg/L,the diffusion coefficient(Ds) and external mass transfer coefficient in the liquid phase(kF) were 3x10^-11 cm^2/min and 4.68 x 10^-6 cm/min,respectively.X-3B approaching the center of PCD-MCH particles could be observed at 360 min.At the end of the third diffusion stage,the Cp at q/qe=0 was 45.20 mg/L,which was close to the homogeneous Cp value of 46 mg/L along the radius of PCD-MCH particles.At pH 3.0-10.0,PCD-MCH showed stable X-3B adsorption capacities.After five regeneration-reuse cycles,the residual adsorption capacity of regenerated PCD-MCH was higher than 892.7 mg/g.The corresponding adsorption mechanism was identified as involving electrostatic interactions,cyclodextrin cavities and hydrogen bonds,of which cyclodextrin cavities showed prominent capture performance towards dye molecules through the formation of inclusion complexes.
文摘The objective of this study was to prepare a new photocatalyst with high activities for degradation of organic pollutants.Coupled ZrO_(2)/ZnO photocatalyst was prepared with a simple precipitation method with cheap raw materials zinc acetate and zirconium oxychloride,and was character-ized by X-ray diffraction(XRD)and transmission electron microscopy(TEM).Reactive brilliant red X-3B was used as a model compound to investigate the photocatalytic activity of synthesized catalysts in water under 254 nm UV irradia-tion.Results show that the optimal calcination temperature and coupling molar ratio of Zr were 350°C and 2.5%,respec-tively.At the calcination temperature of 350°C,ZrO_(2) was dispersed on the surface of hexagonal ZnO in the form of amorphous clusters.The particle size of ZrO_(2)/ZnO decreased with the decrease of calcination temperature and the increase of Zr coupling amount.ZrO_(2)/ZnO has better photocatalytic activity for degradation of reactive brilliant red(RBR)X-3B than pure ZnO and P25-TiO_(2).
