粉煤灰制沸石负载氧化铜处理活性艳红X-3B废水

以粉煤灰作原材料制备沸石负载氧化铜处理活性艳红X-3B废水。采用正交试验法考察了灰/碱比、煅烧温度、晶化时间和灰/水比对出水COD和色度指标的影响,确定了沸石制备最佳工艺条件为灰/碱质量比1.2∶1、焙烧温度600℃、晶化时间6 h和灰/水质量比1∶11,制备的沸石负载氧化铜催化剂与过氧化氢联合催化氧化处理活性艳红X-3B废水,可使出水中COD和色度的指标由原水中的450 mg.L-1和10 240降至90 mg.L-1和3倍(稀释倍数),相应的去除率分别为80.02%和99.97%。

Electrochemical degradation of reactive brilliant red X-3B with the(CeO_2/C)-β-PbO_2-PTFE composite electrode

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.

Brilliant red X-3B uptake by a novel polycyclodextrin-modified magnetic cationic hydrogel:Performance,kinetics and mechanism

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.

A simple and cheap method for preparation of coupled ZrO_(2)/ZnO with high photocatalytic activities

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).