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Surrogate measurements based on excitation-emission matrix fluorescence spectra (EEMs) and ultraviolet-visible absorption spectra (UV-vis) were used to monitor the evolution of dissolved organic matter (DOM) in landfill leachate during a combination of biological and physical-chemical treatment consisting of partial nitritation-anammox (PN-Anammox) or nitrification-denitrification (N-DN) combined with granular active carbon adsorption (GAC). PN-Anammox resulted in higher nitrogen removal (81%), whereas N-DN required addition of an external carbon source to increase nitrogen removal from 24% to 56%. Four DOM components (C1 to C4) were identified by excitation-emission matrix-parallel factor analysis (EEM-PARAFAC). N-DN showed a greater ability to remove humic-like components (C1 and C3), while the protein-like component (C4) was better removed by PN-Anammox. Both biological treatment processes showed limited removal of the medium molecular humic-like component (C2). In addition, the synergistic effect of biological treatments and adsorption was studied. The combination of PN-Anammox and GAC adsorption could remove C4 completely and also showed a good removal efficiency for C1 and C2. The Thomas model of adsorption revealed that GAC had the maximum adsorption capacity for PN-Anammox treated leachate. Salinomycin This study demonstrated better removal of nitrogen and fluorescence DOM by a combination of PN-Anammox and GAC adsorption, and provides practical and technical support for improved landfill leachate treatment.In this paper, the effectiveness of the composite photocatalyst was studied by using manganese dioxide (MnO2)/zirconium dioxide (ZrO2) to degrade diesel pollutants in seawater under visible light.The MnO2/ZrO2 photocatalyst was prepared by co-precipitation and characterized by scanning electron microscopy, X-ray powder diffraction, energy-dispersive spectroscopy and UV-Vis diffuse reflectance spectroscopy analysis. This is the first report on a comprehensive analytical study on the effect of various physio-chemical parameters on diesel degradation using the synthesized MnO2/ZrO2 photocatalysts. The effects of doping ratio of MnO2/ZrO2, dosage, initial diesel concentration, calcination temperature, concentration of H2O2 solutions and illumination time on the diesel degradation were investigated. The degradation of diesel pollution in seawater was optimized by orthogonal experiment. According to the results, the prepared samples were monoclinic form and the MnO2 was successfully doped into the bulk ZrO2. The absorption edge of the MnO2/ZrO2 photocatalysts exhibited red shift, and this red shifts imply enhanced photon absorption under visible light compared with the pure ZrO2. The results showed that under optimum reaction conditions, the degradation rate can reach 92.92%. The result of this study will enable ZrO2 to make more effective use of sunlight and improve the actual value of photocatalytic technology in the field of contaminant treatment.Bioleaching, a technologically and economically feasible technology, is considered as the high efficiency method to improve dewaterability in sewage sludge. The objective of this study was to investigate the effect of different sludge concentrations on bioleaching dewaterability and understand the mechanism of the effect of bioleaching on sludge dewaterability. Variation in pH, oxidation-reduction potential (ORP), capillary suction time (CST), specific resistance to filtration (SRF) and different fractions of extracellular polymeric substances (EPS) including slime EPS (S-EPS), loosely bound EPS (LB-EPS), and tightly bound EPS (TB-EPS) were determined. Different sludge concentrations (5, 10, 15, 20 and 30 g·L-1) were selected to investigate during bioleaching. Results indicated that sludge buffering capacity significantly inhibited bioleaching efficiency as sludge concentrations increased. Optimum enhancements in sludge dewaterability were observed during the 10 g·L-1 sludge concentration treatment, and reached a maximum when the pH was 2.11. The variation of different fractions of EPS revealed that the ratio of S-EPS/TB-EPS significantly affected sludge dewaterability. Principal component analysis and Pearson’s correlation analysis both provided evidence that the higher TB-EPS followed by a very large reduction was positively correlated with sludge dewaterability. However, the increase of protein and DNA in S-EPS content was negatively correlated with sludge dewaterability.Iron (Fe), zirconium (Zr) and titanium (Ti) oxides nanoparticles were each embedded onto a weak acid chelating resin for support using the precipitation method to generate three hybrid adsorbents of hydrated Fe oxide (HFO-P), hydrated Zr oxide (HZO-P) and hydrated Ti oxide (HTO-P). This paper reports on the characterization, performance and potential of these generated nanoadsorbents in the removal of toxic metal ions from acid mine drainage (AMD). The optimum contact time, adsorbent dose and pH for aluminium (Al) (III) adsorption were established using the batch equilibrium technique. The metal levels were measured using inductively coupled plasma-optical emission spectrometry. The scanning electron microscopy-energy dispersive X-ray spectroscopy results confirmed the presence of the metal oxides within the hybrid resin beads. HFO-P, HZO-P and HTO-P adsorbed Al(III) rapidly from synthetic water with maximum adsorption capacities of 54.04, 58.36 and 40.10 mg/g, respectively, at initial pH 1.80 ± 0.02. The adsorption of Al(III) is of the second-order in nature (R2 > 0.98). The nanosorbents removed ten selected metals from environmental AMD and the metal removal efficiency was in the order HTO-P > HZO-P > HFO-P. All three hybrid nanosorbents can be used to remove metals from AMD; the choice would be dependent on the pH of the water to be treated.In environmental biotechnology applications for wastewater treatment, bacterial-based bioprocesses are mostly implemented; on the contrary, the application of fungal-based bioprocesses, is still challenging under non-sterile conditions. In a previous laboratory-scale study, we showed that when specific tannins are used as the sole carbon source, fungi can play a key role in the microbial community, under non-sterile conditions and in the long term. In a previous study, an engineered ecosystem, based on fungal tannin biodegradation, was successfully tested in a laboratory-scale bioreactor under non-sterile conditions. In the present study, a kinetic and stoichiometric characterisation of the biomass developed therein was performed through the application of respirometric techniques applied to the biomass collected from the above-mentioned reactor. To this aim, a respirometric set-up was specifically adapted to obtain valuable information from tannin-degrading fungal biofilms. A mathematical model was also developed and applied to describe both the respirometric profiles and the experimental data collected from the laboratory-scale tests performed in the bioreactor.