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Persulfate (PS)-based technologies have been demonstrated as efficient methods for enhancing the performance of waste activated sludge (WAS) anaerobic fermentation. Except for volatile fatty acids (VFAs), however, some exogenous substances would be also released during this process, which might affect its application as a carbon source for sewage treatment. To fill this knowledge gap, the feasibility of sludge fermentation liquid regulated by Fe/persulfate (PS) (PS-FL) as a carbon source for sewage treatment was investigated in this study. Results indicated that PS-FL exhibits distinct effects on the pollutants removal compared with commercial sodium acetate. It facilitates PO

Sludge-based activated carbon (ZAC) was successfully employed as both adsorbent and catalyst for the oxidation process of reactive yellow 86 (RY86) and reactive black 5 (RB5). Physicochemical prope...

In this work, we adopted the impregnating-baking method to prepare CuOx/granular activated carbon (GAC), CuOx/activated carbon fiber (ACF), and CuOx/powdery activated carbon (PAC) catalysts...

The catalyst of CuOx/granular activated carbon (GAC) was prepared and used as a heterogeneous Fenton-like catalyst for degradation of phenol in the microwave (MW)-induced H2O2 catalytic oxidation process. The prepared catalysts were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), X-ray diffraction (XRD), and N2 adsorption–desorption techniques. Results showed that CuO and Cu2O were loaded on the surface of GAC. Effects of catalyst dosage, H2O2 dosage, pH, MW power, and MW irradiation time on the degradation efficiency were studied. The phenol degradation efficiency reached 99.96%, corresponding to 88.6% chemical oxygen demand (COD) removal under optimal conditions with MW power of 400 W, CuOx/GAC dosage of 3 g/L, H2O2 dosage of 2 mL/L, reaction time 4 min, and pH 4. The combined method of MW/catalyst/H2O2 has been proven to be much more effective toward phenol degradation than using MW alone, catalyst alone, MW/catalyst, MW/H2O2, and catalyst/H2O2 methods. In the presence of CuOx/GAC catalyst, the mechanism of phenol degradation under MW irradiation combined with H2O2 was suggested. A synergistic effect of catalyst, MW, and H2O2 contributes to the high degradation efficiency of phenol. The obtained kinetic equation for MW catalytic oxidation degradation of phenol was in line with first-order kinetic model.

Degradation of humic acid (HA) in heterogeneous electro-Fenton/chlorine processes was investigated using a catalyst of Mn-Cu bimetallic oxides supported on Al-containing MCM-41. The catalyst was synthesized by co-precipitation method and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption–desorption, and X-ray photoelectron spectroscopy (XPS) techniques. The bimetallic oxide catalyst exhibited a higher activity compared to monometallic one. Adding Al in the bimetallic oxide catalyst enhanced the stability of the catalyst, reduced metal ion leaching, increased the initial ratio of Mn3+/Mn4+ and Cu+/Cu2+, and slightly enhanced the degradation efficiency of HA and corresponding chemical oxygen demand (COD). The effect of Mn and Cu content in MCM-41, catalyst dosage, pH value, and initial concentration of HA and salinity on degradation efficiency were investigated. A high COD reduction about 91.5% and general current efficiency (GCE) about 41.7% have been achieved under the optimal conditions of pH 6, salinity 1000 mg/L, catalyst dosage 0.5 g/L, HA sodium salt concentration 200 mg/L, and reaction time 60 min. A possible mechanism for the reaction was suggested. Kinetic analysis showed that HA degradation in the electro-Fenton/chlorine processes was fit with first-order kinetics.

Sludge-based activated carbon (ZAC) was successfully employed as both adsorbent and catalyst for the oxidation process of reactive yellow 86 (RY86) and reactive black 5 (RB5). Physicochemical properties of the prepared sewage sludge-derived activated carbon were evaluated by N

China is one of the large coal mining countries in the world. Coal mining accelerates economic prosperity, as well as engenders a series of environment problems either. One of the most obvious problems is that coal mining changes the landforms around the mining areas. Abundant arable area, garden area, forest area and construction area have been changed under the drive of this dynamic landform. The law that other environment elements change resulting from transformation of one element can be analysed by location theory---Concentric-Circle Mode (or Circle Layer Mode) proposed by professor E. W. Burgess of Chicago University. For the case of Longkou coal mining subsidence area in Shandong province, based on the ground measurement elevation data of the years of 1978, 1989, 1995 and 2004, firstly, this paper considers the DEM data of 1978 before subsidence as standard elevation, and calculates the difference value DEM data of three periods through the difference operation of the other later three-period DEM data and the standard elevation. The coal mining subsidence region and area can be figured out, which is grid region and the overall sum of the grid area with z