Preparation of Ni/GO 0.2 -PAC 0.8 particle electrode and its degradation performance of Cu-EDTA complex

A three-dimensional particle electrode loaded with α-Fe2O3 on powdered activated carbon (PAC) (α-Fe2O3/PAC) was synthesized by the microwave method for removing ammonium nitrogen from wastewater in a three-dimensional electrode system. The α-Fe2O3/PAC electrode was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The effect of the added α-Fe2O3/PAC on the removal of ammonium nitrogen from simulated wastewater was studied by changing the cell voltage, particle dosage, and particle electrode synthesis conditions. Simulated experiments were also carried out on different pollutants under the best experimental conditions and the actual domestic sewage was tested. The results show that the optimal synthesis conditions of the particle electrode are as follows: the ratio of PAC to anhydrous FeCl3 is 1 : 2, and the microwave power is 1000 W for 60 s. After 20 min of electrolysis at 20 V, the ammonium nitrogen removal rate can reach 95.30%.

Electrocatalytic decomplexation of Cu-EDTA and simultaneous recovery of Cu with Ni/GO-PAC particle electrode

This study demonstrates that silver (Ag+) impregnated graphene oxide (GO) reduces anion and natural organic matter (NOM) competition for bromide (Br−) adsorption sites compared with Ag+ impregnated powdered activated carbon (PAC). We impregnated two GO (Tour and Modifier Hummers [MH] method) and one PAC with silver ions. Batch studies were conducted to assess Br− removal in model waters with Br−, chloride (Cl−), bicarbonate (HCO3−), and/or NOM and natural surface waters. In buffered ultrapure water, Tour-Ag, MH-Ag, and PAC-Ag all removed >85% of Br−, while sorbents without Ag+ removed 75% of Br−, MH-Ag removed >50%, and PAC-Ag removed >30%, highlighting that GO-Ag is more effective at removing Br− from water than PAC-Ag (p < 0.05). Scanning electron microscopy and energy dispersive X-ray spectroscopy analysis show that Br− is evenly dispersed on the surface of GO-Ag, indicating possible attachment to oxygen groups and silver on the GO surface. A...

With the development of modern chemical synthesis technology, toxic and harmful compounds increase sharply. In order to improve the removal efficiency of refractory organic matter in waste water, the method of adding powdered activated carbon (PAC) to the system for adsorption was adopted. Through the analysis of organic matter removal rule before and after waste water treatment, it can be found that PAC is easy to adsorb hydrophobic organic matter, while activated sludge is easy to remove hydrophilic and weakly hydrophobic neutral organic matter. Powdered activated carbon-activated sludge SBR system (PAC-AS) system is obviously superior to AS and PAC system in removing organic matter of hydrophilic and hydrophobic components, that is, biodegradation and PAC adsorption are additive. Compared with the control system, the Chemical Oxygen Demand (COD) removal rate of refractory substances increased by 8.36%, and PAC had a good adsorption effect on small molecular weight organic compounds, but with the increase of molecular weight of organic compounds, the adsorption effect of PAC gradually weakened, and it had no adsorption effect on macromolecular organic compounds. Based on the research of fuzzy control theory, an Agent control system for ozone oxidation process of industrial waste water based on Mobile Agent Server (MAS) theory was established, which was realized by fuzzy control method. The simulation results showed strong stability and verified the feasibility and adaptability of the distributed intelligent waste water treatment system based on MAS theory in the actual control process.

Graphene oxide (GO) membranes become emerging efficient filters for molecular or ionic separation due to their well-defined two-dimensional nanochannels formed by closely spaced GO sheets and tunable physicochemical properties. The stability of GO membranes in aqueous solutions is a prerequisite for their applications. Here we show a novel and easy strategy for fabricating GO membranes with strong stability in aqueous solutions and controllable lamellar spacing by simply doping with partially reduced graphene oxide (prGO) sheets. With our prGO-doping strategy, the interlayer stabilizing force in GO membranes is enhanced due to the weakened repulsive hydration and enhanced π-π attraction between GO sheets; as a result, the fabricated GO membranes are featured with controllable lamellar spacing and extraordinary stability in water or even strong acid and base solutions as well as strong mechanical properties, which will expand the application scope of GO membranes and provide ever better performances in their applications with aqueous solution environments.

Highly effective degradation of 2,4-Dichlorophenoxyacetic acid herbicide in a three-dimensional sono-electro-Fenton (3D/SEF) system using powder activated carbon (PAC)/Fe3O4 as magnetic particle electrode

Three-dimensional electro-Fenton degradation of ciprofloxacin catalyzed by CuO doped red mud particle electrodes: Electrodes preparation, kinetics and mechanism

Due to the intricate composition and recalcitrant nature of coking wastewater, the biochemical effluent often fails to meet standards. This study explored the preparation of particle electrodes, utilizing activated carbon powder (PAC) loading single-element Fe, Co, and Ni, as well as dual-element Ni–Fe and Co–Fe as catalyst. The particle electrode system was integrated with persulphate (PS) activation to enhance its performance. The effects of potassium persulphate (KPS) dosages, currents, and Ni:Fe ratios were investigated. The results showed that bimetallic particle electrodes outperformed their monometallic particle electrodes. Among the five electrode materials, Ni–Fe/PAC achieved the best degradation efficiency of 84.4% and the lowest energy consumption of 19.73 kW·h·kg−1 COD. When the initial concentrations of TOC and COD were set at 300 and 280 mg L−1, the Ni–Fe/PAC with 5 mmol L−1 KPS achieved removal efficiencies of 61.7 and 84.4%, respectively. The metals on Ni/PAC and Co/PAC existed in the zero-valent state, while Fe on Fe/PAC was present as Fe2O3. Co–Fe/PAC exhibited the formation of CoFe2O4 oxides. Ni–Fe/PAC possessed the lowest hydrogen evolution reaction potential (−0.28 V), and the highest oxygen evolution potential (2.4 V), and reached an electrochemical active surface area (ECSA) of 236.3 cm2. Cyclic voltammetry (CV) curves indicated that the direct redox reactions and indirect oxidation of pollutants occurred concurrently. Both •OH and ⋅ SO 4 − radicals played crucial roles during the degradation processes. The degradation efficiency of organic matter was as follows: benzene compounds (88.4%) >heterocyclic compounds (75.3%) >polycyclic aromatic hydrocarbons (53.9%).

Inhibition of bromate formation in the O3/PMS process by adding low dosage of carbon materials: Efficiency and mechanism

Fabrication and electrochemical characterization of graphene-oxide supercapacitor electrodes with activated carbon current collectors on graphite substrates

Effective column adsorption of triclosan from pure water and wastewater treatment plant effluent by using magnetic porous reduced graphene oxide

Preparation of Fe-loaded needle coke particle electrodes and utilisation in three-dimensional electro-Fenton oxidation of coking wastewater

Electrocatalytic degradation of nitrogenous heterocycles on confined particle electrodes derived from ZIF-67

Three-dimensional electrochemical oxidation (3D-ECO) technology is considered as one of the most promising advanced oxidation processes for degrading refractory organic pollutants. However, the preparation of the particle electrodes (PEs) is a key factor for industrial applications. In this study, a new Al2O3-based PE was proposed for 3D-ECO system. The prepared PEs were characterized by scanning electron microscopy, energy-dispersive X-ray microscopy, and X-ray diffraction to examine their morphology, elementary composition, and amount of CuFe2O4 respectively. Experiments comparing different conditions showed that 3D-ECO system equipped with prepared PEs and persulphate (PS) was more efficient in degradingp-nitrophenol (PNP). Based on these results, the critical process parameters of the dosage of the PEs, initial PS concentration, and current density for 3D-ECO using the proposed PEs were examined. Under the optimized operations, the PNP removal rate reached 80.23% with a low electrical energy consumption of 3.97 kW h/mg PNP, which was significantly better than the 69.16% and 9.50 kW·h/mg PNP under conventional ECO process. Moreover, cycling experimental results indicated that the performance of the PEs had no declining trend during the 5 h test period, suggesting acceptable stability of the particles without particle damage or mass loss. These investigations provide a novel route for preparing high-efficiency PEs.

Bisphenol A (BPA) is a commonly used plasticizer incorporated into the parent plastics during manufacturing. It is classified as an emerging contaminant that is continually detected in aquatic environments and is listed as an endocrine disrupting chemical confirmed to be associated with cardiovascular disease and reproductive disorder. The hazardous aspects of BPA require the development of innovative methods for its degradation. Among these techniques, adsorption and electrochemical degradation are considered to be particularly attractive due to their high efficiency, versatility and environmental friendliness, since they do not require any other chemicals. The use of graphene oxide (GO) was investigated as an adsorbent and as a particle electrode for the removal of BPA from aqueous solutions. The adsorptive behaviors of GO toward BPA were investigated in batch mode under darkness, visible light and UV light conditions. GO was used as particle electrode in a three-dimensional electro-oxidation (3D-EO) process established by an Ru/TiO2 anode and the effects of current density values ranging from 10 to 50 mA/cm2 were investigated. The obtained results revealed that the 3D electrochemical degradation process achieved a higher BPA removal efficiency than adsorption, showing that 3D-EO with a graphene oxide particle electrode may significantly improve BPA removal efficiency.