Characterization of suspended solids and particle-bound heavy metals in a first flush of highway runoff

To investigate the dynamic characteristics of total suspended solids (TSS) and their particle-bound heavy metals in a first flush, the runoff sampling together with its flow rate measuring was conducted for three rainfall events at outfalls of highway in Shanghai from June to September 2007. Field samples were analyzed to determine the concentrations of TSS and particle-bound heavy metals, such as Zn, Pb, and Cu. Results show that the wash off behavior of TSS under varying runoff rate condition can be explained by different antecedent dry weather period (ADWP). Contribution of fine fraction (<45 μm) to TSS was generally higher than that of coarse fraction (>45 μm). When the runoff flow increased obviously, a significant contribution of the coarse fraction was observed for a certain rainfall events with long antecedent dry weather condition. The changes of total metals concentration and particle-bound metal concentrations were strongly dependent on the TSS variation. TSS was generally well correlated with most particulate-bound heavy metals. Of the heavy metals, the concentration of Zn was found considerably high and that of Pb was significantly low at North Zhongshan 2 Road, in Shanghai, China, but they are still within the range reported in the literature. Fluctuation of heavy metal contents in the coarse fraction during a first flush period was more significant compared with that in the fine fraction. The results will assist in the development of effective control strategies to minimize heavy metals and solids in highway runoff.

Photon-Ion Catalysis Synergy Material and Its Application

The co-operation action mechanism and model of photon-ion catalysis synergy material composed of thallium and valency-variable rare earth elements and semiconductor oxide were proposed. The radiation catalysis reactions of water and oxygen assisted by the synergy material that could largely increase electron, free radical and negative ion products were discussed. The applications of photon-ion catalysis synergy material in areas of air cleaning material, antibacterial material , healthy material and energy resource material were suggested.

冶金企业污泥的特征及对环境的影响

1.前言就对环境造成的污染而言,钢铁厂仅次于化工厂和电站,它所产生的废物(固体和液体)多达一百种以上。在某些情况下,由于这些废物的物理化学成分不同,造成工艺处理上的困难和环境公害。本文作者根据已完成的研究,介绍了这些废物的特点并且提出了对他们的处理看法。

Photoassisted Fenton degradation of phthalocyanine dyes from wastewater of printing industry using Fe(Ⅱ)/γ-Al_2O_3 catalyst in up-flow fluidized-bed

Fe（II）/γ-Al2O3 powders synthesized using the dipping method were produced from a mixed aqueous solution containing aluminium oxide （γ-Al2O3） and iron（II）-precursor （FeSO4）, and used for photoFenton degradation of phthalocyanine dyes （PCs） under ultraviolet （UV） irradiation in an up-flow fluidized bed. The catalysts were characterized by XRD, ESCA, BET, EDS and SEM. The results showed that Fe2＋ ion was compounded on the γ-Al2O3 carder. The effects of different reaction parameters such as catalyst activity, dosage and solution pH on the decolorization of PCs were assessed. Results indicated that maximum decolorization （more than 95%） of PCs occurred with 20 wt% Fe（II）/γ-Al2O3 catalyst （dosage of 60 g/L） using a combination of UV irradiation and heterogeneous Fenton system. The degradation efficiency of PCs increases as pH decreases, exhibiting a maximum efficiency at pH 3.5. The recycled catalyst was capable of repeating three runs without a significant decrease in treatment efficiency, and this demonstrated the stability and reusability of catalyst.

Theoretical study on magneto-structural correlation of trinuclear copper (II) complex with the hydroxo bridge and bidentate syn-syn carboxylate group

The theoretical study on magneto- structural correlation in linear trinuclear Cu (II) com- plex bridged by hydroxo group and bidentate formato group has been performed using the broken symme- try approach with the framework of density functional theory (DFT-BS). The magnetic coupling constant for the model complex is 70.97 cm?1, comparable with the experimentally measured J value (77 cm?1). The calculated results show that the magnetic coupling interaction firstly slightly increases with the changes of the coordination environment around the terminal Cu atoms from a distorted square pyramid to a trigonal bi-pyramid, and decreases subsequently. In the course of changes, the sign of J value shifts from positive to negative. The magnetic coupling interac- tion is sensitive to coordination environment of the terminal Cu. The calculated results also reveal that the ferromagnetic coupling arises from the counter- complementarity of the hydroxo and formato bridges. Molecular orbital analysis validates the conclusion.

Energy-efficient removal of carbamazepine in solution by electrocoagulation-electrofenton using a novel P-rGO cathode

In this study,carbamazepine(CBZ)decay in solution has been studied by coupling electro-coagulation with electro-Fenton(EC-EF)with a novel P-rGO/carbon felt(CF)cathode,aiming to accelerate the in-situ generation of·OH,instead of adding Fe2+and H2O2.Firstly,the fabri-cated P-rGO and its derived cathode were characterized by XRD,SEM,AFM,XPS and electro-chemical test(EIS,CV and LSV).Secondly,it was confirmed that the performance in removal efficiency and electric energy consumption(EEC)by EC-EF(kobs=0.124 min^(-1),EEC=43.98 kWh/kg CBZ)was better than EF(kobs=0.069 min^(-1),EEC=61.04 kWh/kg CBZ).Then,P-rGO/CF(kobs=0.248 min^(-1),EEC=29.47 kWh/kg CBZ,CE=61.04%)showed the best performance in EC-EF,among all studied heteroatom-doped graphene/CF.This superior performance may be associated with its largest layer spacing and richest C=C,which can promote the electron transfer rate and conductivity of the cathode.Thus,more H2O2 and·OH could be produced to degrade CBZ,and almost 100%CBZ was removed with kobs being 0.337 min^(-1) and the EEC was only 24.18 kWh/kg CBZ,under the optimal conditions(P-rGO loading was 6.0 mg/cm^(2),the current density was 10.0 mA/cm^(2),the gap between electrode was 2.0 cm).Additionally,no matter the influent is acidic,neutral or alkaline,no additional pH adjustment is required for the effluent of EC-EF.At last,an inconsecutive empirical kinetic model was firstly estab-lished to predict the effect of operating parameters on CBZ removal.

A novel insight of degradation ibuprofen in aqueous by catalytic ozonation with supported catalyst:Supports effect on ozone mass transfer

Catalytic ozonation is an effective wastewater purification process.However,the low ozone mass transfer in packed bubble columns leads to low ozone utilization efficiency(OUE),poor organic degradation performance,and high energy consumption.Therefore,there is an urgent need to develop efficient supported catalysts that can enhancemass transfer and performance.However,the reaction mechanism of the support on ozone mass transfer remains unclear,which hinders the development of catalytic ozonation applications.In this study,lava rocks(LR)-supported catalysts,specifically CuMn_(2)O_(4)@LR and MnO_(2)–Co_(3)O_(4)@LR,were proposed for catalytic ozonation of IBP degradation due to their superior catalytic activity,stability,and high OUE.Addition of CuMn_(2)O_(4)@LR or MnO_(2)–Co_(3)O_(4)@LR increased IBP removal efficiency from 85%to 91%or 88%,and reduced energy consumption from 2.86 to 2.14 kWh/m^(3)or 2.60 kWh/m^(3),respectively.This improvement was attributed to LRsupported catalysts enhancing mass transfer and promoting O3 decomposition to generate•OH and•O_(2)^(−),leading to IBP degradation.Furthermore,this study investigated the effects of ozone dose,supporter sizes,and catalyst components on ozone-liquid mass transfer.The results revealed that the size of the supporter influenced stacked porosity and consequently affected ozone mass transfer.Larger-sized LR(kLa=0.172 min^(−1))exhibited better mass transfer compared to smaller-sized supports.Based on these findings,it was concluded that both CuMn_(2)O_(4)@LR and MnO_(2)–Co_(3)O_(4)@LR are potential catalysts for catalytic ozonation in residual IBP degradation of pharmaceutical wastewater,and LR showed good credibility as a catalyst supporter.Understanding the effects of supporters and active components on ozone mass transfer provides a fundamental principle for designing supported catalysts in catalytic ozonation applications.