Aspergillus ficuum was immobilized with sodium alginate, and decolourization of Reactive Brilliant Blue KN-R was studied on immobilized and free Aspergillus ficuum. The optimal preparation condition of the strain immo...Aspergillus ficuum was immobilized with sodium alginate, and decolourization of Reactive Brilliant Blue KN-R was studied on immobilized and free Aspergillus ficuum. The optimal preparation condition of the strain immobilization was obtained by the orthogonal test, it is sodium alginate 3%, CaCl_2 5%, wet mycelia 30 g/L, calcific time 8 h. It was found that the immobilized cells could effectively decolourize Reactive Brilliant Blue KN-R, the optimum temperature and pH were 33℃ and 5.0, respectively. The kinetics study of decolourization of immobilized cells showed that the decolourization of Aspergillus ficuum immobilized conformed to zero-order reaction model. The decolourization efficiency of immobilized cell compared with that of free cell in different physical conditions. Results showed that the decolourization of immobilized cells with mycelia had the best efficiency. The immobilized cells could be reused after the first decolourization.展开更多
Almost all the studies both domestic and international using white rot fungus for dye wastewater treatment are performed under sterile conditions. However, it is obviously unpractical that wastewater with dyes is trea...Almost all the studies both domestic and international using white rot fungus for dye wastewater treatment are performed under sterile conditions. However, it is obviously unpractical that wastewater with dyes is treated under sterile conditions. A feasible study was made for using white rot fungus Phanerochaete chrysosporium to degrade reactive brilliant red K-2BP dye under non-sterile conditions. The results showed that there was no decolorizing effect under non-sterile condition if white rot fungus was incubated under non-sterile condition, and the decolorization was always near to 0% during decolorizing test for 3 d; in the meantime, a lot of yeast funguses were found in liquid medium when white rot fungus was incubated under non-sterile conditions; however, if white rot fungus was incubated under sterile condition firstly, its decolorization was above 90% under non-sterile condition, which was similar to that of sterile condition. So we point out that the treating process for wastewater with dyes should be divided into two stages. The first stage is that white rot fungus should be incubated under sterile conditions, and the second stage is that reactive brilliant red K-2BP is decolorized under non-sterile conditions. The method not only save the operation cost which decolorizing reactive brilliant red K-2BP under sterile condition, but also provide the feasibility for using white rot fungus to degrade wastewater with dyes under non-sterile conditions.展开更多
In this study,the electrochemical oxidation of reactive brilliant orange X-GN dye with a boron-doped diamond(BDD)anode was investigated.The BDD electrodes were deposited on the niobium(Nb)substrates by the hot filamen...In this study,the electrochemical oxidation of reactive brilliant orange X-GN dye with a boron-doped diamond(BDD)anode was investigated.The BDD electrodes were deposited on the niobium(Nb)substrates by the hot filament chemical vapor deposition method.The effects of processing parameters,such as film thickness,current density,supporting electrolyte concentration,initial solution pH,solution temperature,and initial dye concentration,were evaluated following the variation in the degradation efficiency.The microstructure and the electrochemical property of BDD were characterized by scanning electron microscopy,Raman spectroscopy,and electrochemical workstation;and the degradation of X-GN was estimated using UV-Vis spectrophotometry.Further,the results indicated that the film thickness of BDD had a significant impact on the electrolysis of X-GN.After 3 h of treatment,100%color and 63.2%total organic carbon removal was achieved under optimized experimental conditions:current density of 100 mA/cm2,supporting electrolyte concentration of 0.05 mol/L,initial solution pH 3.08,and solution temperature of 60°C.展开更多
The influence of a Reactive Brilliant Red X-3B (RBR X-3B) dye on the peroxidase isoenzyme ofPhanerochaete chrysosporium was determined, and the biofilm structure in a white rot fungal continuous membrane bioreactor ...The influence of a Reactive Brilliant Red X-3B (RBR X-3B) dye on the peroxidase isoenzyme ofPhanerochaete chrysosporium was determined, and the biofilm structure in a white rot fungal continuous membrane bioreactor (MBR) was also investigated by scanning electron microscope (SEM). The variation of peroxidase isoenzyme and the decolorization rate in the continuous MBR were evaluated. The results showed that the 100 mg/L RBR X-3B could stimulate the production of the peroxidase isoenzyme in the shaking-flask culture. In addition, two new peroxidase isoenzyme bands with relative mobility (Rf) value of 0.27 and 0.28 appeared, but the activity was lower than the blank control of 11 d. In the continuous MBR, the system worked stably during the first 60 d, the main peroxidase isoenzyme bands existed and three new bands with Rf value of 0.10, 0.27, and 0.28 appeared. Meanwhile, the biofilm grew well and the average decolorization rate could reach 90.6%. But the bands of peroxidase isoenzyme decreased rapidly at day 65, only two bands with Rf value 0.24 and 0.26 existed, and the decolorization rate decreased to 78.3%. Therefore, 5 bottles of P. chrysosporium mycelial pellet were added into the MBR, and then the activity of the peroxidase isoenzyme and the decolorization rate had a slight recovery. Finally, the decolorization rate finally decreased to 75.2%. These results contribute to a comprehensive understanding of the variation of peroxidase isoenzyme and biofilm in continuous MBR by white rot fungi.展开更多
A study of the decolorization of reactive brilliant blue in an aqueous solution using Fe-Mn-sepiolite as a heterogeneous Fenton-like catalyst has been performed. The Fourier transform infrared (FTIR) spectra of the ...A study of the decolorization of reactive brilliant blue in an aqueous solution using Fe-Mn-sepiolite as a heterogeneous Fenton-like catalyst has been performed. The Fourier transform infrared (FTIR) spectra of the catalyst showed bending vibrations of the Fe-O. The Xray diffraction (XRD) patterns of the catalyst showed characteristic diffraction peaks of α-Fe203, γ-Fe203 and MnO. A four factor central composite design (CCD) coupled with response surface methodology (RSM) was applied to evaluate and optimize the important variables (catalyst addition, hydrogen peroxide dosage, initial pH value and initial dye concentration). When the reaction conditions were catalyst dosage = 0.4 g, [H202]= 0.3 mL, pH= 2.5, [reactive brilliant blue]o = 50mg·L-1, and volume of solution = 500 mL at room temperature, the decolorization efficiency of reactive brilliant blue was 91.98% within 60min. Moreover, the Fe-Mn-sepiolite catalyst had good stability for the degradation of reactive brilliant blue even after six cycles. Leaching of iron ions ( 〈 0.4 mg·L-l) was observed. The decoloring process was reactive brilliant blue specific via a redox reaction. The benzene ring and naphthalene ring were first oxidized to open ring; these were then oxidized to the alcohol and carboxylic acid. The reactive brilliant blue was decom- posed mainly by the attack of .OH radicals including surface-bound .OH radicals generated on the catalyst surface.展开更多
Titanium dioxide coated on activated carbon(AC) with Fe ions doping(Fe-TiO2/AC) composite was prepared by an improved sol-gel method.The photocatalytic activities were tested by photocatalytic degradation of reactive ...Titanium dioxide coated on activated carbon(AC) with Fe ions doping(Fe-TiO2/AC) composite was prepared by an improved sol-gel method.The photocatalytic activities were tested by photocatalytic degradation of reactive brilliant red K2G in solution.The results show that in comparison with the agglomeration of pure TiO2,the TiO2 nanoparticles are well dispersed in the AC matrix,of which sizes are decreased with Fe ions doping.Additionally,the iron species on TiO2 of composite are Fe2O3 and FeO,which do not affect the crystalline structures of TiO2 nanoparticles.The AC matrix and iron doping content influence the fluorescence intensity of composite due to their effects on recombination probability of hole-electron pairs.Compared with TiO2,0.3% Fe-TiO2,TiO2/AC,0.5% Fe-TiO2/AC and 0.1% Fe-TiO2/AC,the 0.3% Fe-TiO2/AC shows the highest photoactivity with the complete mineralization of K2G for finite time due to the optimum Fe ions content and AC matrix.Furthermore,the kinetic constant(k=0.0229 min-1) of 0.3% Fe-TiO2/AC composite is more than the sum of both TiO2/AC(0.0154 min-1) and 0.3% Fe-TiO2(0.0057 min-1) because coexistence of the AC and Fe ions has an enlarging effect on improving the photoactivity of TiO2.展开更多
本研究通过建立光催化燃料电池/过二硫酸盐(PFC/PS)体系降解活性艳兰染料(KN-R),考察了PFC/PS体系的催化活性及产电效能。结果表明,PFC与PS的耦合可大幅提升KN-R的脱色,处理120 min后,KN-R的脱色率达到99.37%。PFC协同PS体系可以提高电...本研究通过建立光催化燃料电池/过二硫酸盐(PFC/PS)体系降解活性艳兰染料(KN-R),考察了PFC/PS体系的催化活性及产电效能。结果表明,PFC与PS的耦合可大幅提升KN-R的脱色,处理120 min后,KN-R的脱色率达到99.37%。PFC协同PS体系可以提高电池性能,产生更多电能。与单独PFC相比,其最大输出功率密度(Pmax)从0.0003 m W/cm^(2)增加到0.0012 m W/cm^(2)。水中常见无机阴离子对PFC/PS协同体系降解KN-R及产电性能具有一定的促进作用。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
文摘Aspergillus ficuum was immobilized with sodium alginate, and decolourization of Reactive Brilliant Blue KN-R was studied on immobilized and free Aspergillus ficuum. The optimal preparation condition of the strain immobilization was obtained by the orthogonal test, it is sodium alginate 3%, CaCl_2 5%, wet mycelia 30 g/L, calcific time 8 h. It was found that the immobilized cells could effectively decolourize Reactive Brilliant Blue KN-R, the optimum temperature and pH were 33℃ and 5.0, respectively. The kinetics study of decolourization of immobilized cells showed that the decolourization of Aspergillus ficuum immobilized conformed to zero-order reaction model. The decolourization efficiency of immobilized cell compared with that of free cell in different physical conditions. Results showed that the decolourization of immobilized cells with mycelia had the best efficiency. The immobilized cells could be reused after the first decolourization.
基金The National Natural Science Foundation of China (No. 50478010) and the Chinese Postdoctoral Science Foundation (No.20040350022)
文摘Almost all the studies both domestic and international using white rot fungus for dye wastewater treatment are performed under sterile conditions. However, it is obviously unpractical that wastewater with dyes is treated under sterile conditions. A feasible study was made for using white rot fungus Phanerochaete chrysosporium to degrade reactive brilliant red K-2BP dye under non-sterile conditions. The results showed that there was no decolorizing effect under non-sterile condition if white rot fungus was incubated under non-sterile condition, and the decolorization was always near to 0% during decolorizing test for 3 d; in the meantime, a lot of yeast funguses were found in liquid medium when white rot fungus was incubated under non-sterile conditions; however, if white rot fungus was incubated under sterile condition firstly, its decolorization was above 90% under non-sterile condition, which was similar to that of sterile condition. So we point out that the treating process for wastewater with dyes should be divided into two stages. The first stage is that white rot fungus should be incubated under sterile conditions, and the second stage is that reactive brilliant red K-2BP is decolorized under non-sterile conditions. The method not only save the operation cost which decolorizing reactive brilliant red K-2BP under sterile condition, but also provide the feasibility for using white rot fungus to degrade wastewater with dyes under non-sterile conditions.
基金Project(2016YEB0301402) supported by the National Key Research and Development Program of ChinaProject(51601226) supported by the National Natural Science Foundation of China+1 种基金Project supported by the Open-End Fund for the Valuable and Precision Instruments of Central South University,ChinaProject supported by State Key Laboratory of Powder Metallurgy,China
文摘In this study,the electrochemical oxidation of reactive brilliant orange X-GN dye with a boron-doped diamond(BDD)anode was investigated.The BDD electrodes were deposited on the niobium(Nb)substrates by the hot filament chemical vapor deposition method.The effects of processing parameters,such as film thickness,current density,supporting electrolyte concentration,initial solution pH,solution temperature,and initial dye concentration,were evaluated following the variation in the degradation efficiency.The microstructure and the electrochemical property of BDD were characterized by scanning electron microscopy,Raman spectroscopy,and electrochemical workstation;and the degradation of X-GN was estimated using UV-Vis spectrophotometry.Further,the results indicated that the film thickness of BDD had a significant impact on the electrolysis of X-GN.After 3 h of treatment,100%color and 63.2%total organic carbon removal was achieved under optimized experimental conditions:current density of 100 mA/cm2,supporting electrolyte concentration of 0.05 mol/L,initial solution pH 3.08,and solution temperature of 60°C.
基金supported by the National High Technology Research and Development Program (863) of China (No. 2006AA06Z331)the National Natural Science Foundation of China (No. 50278034)
文摘The influence of a Reactive Brilliant Red X-3B (RBR X-3B) dye on the peroxidase isoenzyme ofPhanerochaete chrysosporium was determined, and the biofilm structure in a white rot fungal continuous membrane bioreactor (MBR) was also investigated by scanning electron microscope (SEM). The variation of peroxidase isoenzyme and the decolorization rate in the continuous MBR were evaluated. The results showed that the 100 mg/L RBR X-3B could stimulate the production of the peroxidase isoenzyme in the shaking-flask culture. In addition, two new peroxidase isoenzyme bands with relative mobility (Rf) value of 0.27 and 0.28 appeared, but the activity was lower than the blank control of 11 d. In the continuous MBR, the system worked stably during the first 60 d, the main peroxidase isoenzyme bands existed and three new bands with Rf value of 0.10, 0.27, and 0.28 appeared. Meanwhile, the biofilm grew well and the average decolorization rate could reach 90.6%. But the bands of peroxidase isoenzyme decreased rapidly at day 65, only two bands with Rf value 0.24 and 0.26 existed, and the decolorization rate decreased to 78.3%. Therefore, 5 bottles of P. chrysosporium mycelial pellet were added into the MBR, and then the activity of the peroxidase isoenzyme and the decolorization rate had a slight recovery. Finally, the decolorization rate finally decreased to 75.2%. These results contribute to a comprehensive understanding of the variation of peroxidase isoenzyme and biofilm in continuous MBR by white rot fungi.
文摘A study of the decolorization of reactive brilliant blue in an aqueous solution using Fe-Mn-sepiolite as a heterogeneous Fenton-like catalyst has been performed. The Fourier transform infrared (FTIR) spectra of the catalyst showed bending vibrations of the Fe-O. The Xray diffraction (XRD) patterns of the catalyst showed characteristic diffraction peaks of α-Fe203, γ-Fe203 and MnO. A four factor central composite design (CCD) coupled with response surface methodology (RSM) was applied to evaluate and optimize the important variables (catalyst addition, hydrogen peroxide dosage, initial pH value and initial dye concentration). When the reaction conditions were catalyst dosage = 0.4 g, [H202]= 0.3 mL, pH= 2.5, [reactive brilliant blue]o = 50mg·L-1, and volume of solution = 500 mL at room temperature, the decolorization efficiency of reactive brilliant blue was 91.98% within 60min. Moreover, the Fe-Mn-sepiolite catalyst had good stability for the degradation of reactive brilliant blue even after six cycles. Leaching of iron ions ( 〈 0.4 mg·L-l) was observed. The decoloring process was reactive brilliant blue specific via a redox reaction. The benzene ring and naphthalene ring were first oxidized to open ring; these were then oxidized to the alcohol and carboxylic acid. The reactive brilliant blue was decom- posed mainly by the attack of .OH radicals including surface-bound .OH radicals generated on the catalyst surface.
基金Supported by the Education Department Foundation of Hunan Province (Grant No. 08B063)Science and Natural Science Foundation of Hunan Province (Grant No. 09JJ6101)
文摘Titanium dioxide coated on activated carbon(AC) with Fe ions doping(Fe-TiO2/AC) composite was prepared by an improved sol-gel method.The photocatalytic activities were tested by photocatalytic degradation of reactive brilliant red K2G in solution.The results show that in comparison with the agglomeration of pure TiO2,the TiO2 nanoparticles are well dispersed in the AC matrix,of which sizes are decreased with Fe ions doping.Additionally,the iron species on TiO2 of composite are Fe2O3 and FeO,which do not affect the crystalline structures of TiO2 nanoparticles.The AC matrix and iron doping content influence the fluorescence intensity of composite due to their effects on recombination probability of hole-electron pairs.Compared with TiO2,0.3% Fe-TiO2,TiO2/AC,0.5% Fe-TiO2/AC and 0.1% Fe-TiO2/AC,the 0.3% Fe-TiO2/AC shows the highest photoactivity with the complete mineralization of K2G for finite time due to the optimum Fe ions content and AC matrix.Furthermore,the kinetic constant(k=0.0229 min-1) of 0.3% Fe-TiO2/AC composite is more than the sum of both TiO2/AC(0.0154 min-1) and 0.3% Fe-TiO2(0.0057 min-1) because coexistence of the AC and Fe ions has an enlarging effect on improving the photoactivity of TiO2.
文摘本研究通过建立光催化燃料电池/过二硫酸盐(PFC/PS)体系降解活性艳兰染料(KN-R),考察了PFC/PS体系的催化活性及产电效能。结果表明,PFC与PS的耦合可大幅提升KN-R的脱色,处理120 min后,KN-R的脱色率达到99.37%。PFC协同PS体系可以提高电池性能,产生更多电能。与单独PFC相比,其最大输出功率密度(Pmax)从0.0003 m W/cm^(2)增加到0.0012 m W/cm^(2)。水中常见无机阴离子对PFC/PS协同体系降解KN-R及产电性能具有一定的促进作用。
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.