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The surface properties and performance of activated carbon (AC) used for catalytic ozonation were investigated after nitric acid modification (N-AC) and Cu (II)-loaded (N-Cu-AC). The results showed that the nitric acid modification could increase the amount of surface functional groups of AC. As a result, the adsorption capacity and catalytic activity of AC could be improved. The surface functional groups and Cu (II)-loaded of N-Cu-AC showed a synergistic effect on catalytic ozonation, where the catalytic activity of Cu (II)-loaded was more stable. N-Cu-AC was an effective and reusable catalyst for catalytic ozonation. The highest TOC removal efficiency of 58.0% could be achieved when N-Cu-AC was used for 60 min-catalytic ozonation treatment of acid red 3R.

The structure and surface chemical properties of activated carbon after nitric acid modification and their influences on adsorption and catalytic ozonation of acid red 3R were investigated. The results showed that both specific surface area and micropore volume of activated carbon decreased, but mesopore volume increased after nitric acid modification. The adsorption capacity and catalytic ozonation performance of modified activated carbon were influenced due to the increased surface acidic functional groups. The adsorption capacity of modified activated carbon was enhanced under acidic condition due to dispersion interaction between increased surface acidic functional groups and acid red 3R. The increase in surface acidic functional groups of activated carbon was also considered to be responsible for improvement of the catalytic ozonation of acid red 3R under alkaline condition, because of their participation in the ozone decomposition and OH generation.

Using granular activated carbon (GAC) as electric particle electrode and heterogeneous catalyst loaded metal oxide to replace insulated particle in bipolar packing bed cell (BPBC), the electro-heterogeneous catalytic oxidation system was constructed. Adopting impregnation method to prepare γ-Al2O3 supported catalysts containing Cu and Ce, it was evenly mixed with GAC to construct packing materials. Using stainless steel as anode, porous graphite as cathode and packing materials between them, landfill leachate was treated by an electro-catalytic oxidation process and COD removal efficiency was studied. The activity of catalysts was explored, and using scanning electron microscope (SEM) and X-ray diffraction (XRD), the microstructure and morphology were characterized. The operating parameters such as cell voltage, initial pH, airflow and inter-electrode distance were also investigated. The results showed that when the metal ion concentration in soaking solution was 2% for Cu, 9% for Ce, the activity of prepared catalyst was the highest. Under the conditions of an applied voltage of 15.0 V, pH of 7.0, airflow of 0.08 m3/h, and an inter-electrode distance of 3.0 cm, the removal efficiencies of COD reached 92.9%. Qualitative analysis of the interim products was carried out, adopting ultraviolet-visible spectrum, and the mechanism of electro-heterogeneous catalytic oxidation reaction was discussed. The whole degradation involves two main processes: electro-oxidation and electro-coagulation.

Methanogens play an important role in the anaerobic digestion and production of methane, and show significant influence on the performance of anaerobic wastewater treatment process. Then the methanogens in anaerobic granular sludge samples from full-scale UASB bioreactors treating avermectin or starch wastewater were detected by FISH using 16S rRNA gene-based probe and functional gene-based probes. The results showed that the hybridization of methanogens in simultaneous FISH with mcrA gene-based and 16S rRNA gene-based probes was high coincident and the coincidence degree was about 60%-80%, implying the preferable hybridization consistency between functional gene-based probe and 16S rRNA gene-based probe. The relative abundance of methanogens obtained in FISH analysis using 16S rRNA gene-based probe seemed higher than that using functional gene-based probes, indicating that functional gene could provide more specific detection of methanogens than 16S rRNA gene probably. For functional gene-based probes, the methanogen-specificity was in the following order: mcrA＜F420＜mtr. During the development process of both granular sludge samples, the maximum relative abundance of methanogens was obtained at its mature phase using all probes. The relative abundance of methanogens in the sludge sample treating avermectin wastewater was lower than that treating starch wastewater, indicating smaller methanogenic population in the sludge sample treating avermectin wastewater due to inhibitory effect of antibiotic residue on methanogens probably.

In order to investigate ecotoxicity effect of 2,4-dinitrotoluene (2,4-DNT) to freshwater fish(Brocarded carp), the acute toxicity test and the sub-lethal expriment were conducted in lab. The acute toxicity test show that 96h LC50 value of 2,4-DNT to Brocarded carp is 19.67 mg/L. Its toxicity rating is moderately toxic to fish. Based on the result of the acute toxicity test, fish was exposed to different concentrations (1/2LC50, 1/4LC50, 1/16LC50, 1/256LC50, surface water standard concentration) and killed at 3, 7, 10 and 14 day after exposure. The activities of Superoxide Dismutase (SOD) and Catalase (CAT) in liver tissue were analyzed. The results indicated the activities of SOD and CAT were inhibited from the third day in all treatment groups at post-exposure, they were lower than those of the control group (p＜0.01). The SOD and CAT activities of the control group were stable during 14-days. The CAT and SOD activities had the same changing trend and they were unstable under the pollution stress. The CAT enzyme was more sensitive than SOD enzyme under pollution stress. The results demonstrate that the SOD and CAT activities of liver in Brocarded Carp might be the promising biomarker of 2,4-DNT exposure to freshwater fish. Therefore it is suggested that the couple index of SOD and CAT could be used as biomarker of nitroaromatics compounds, when their pollutions affected living beings in aquatic environment.