Effect of Operating Conditions and Water Matrix on the Performance of UV Combined Electrochemical Process for Treating Chloride-containing Solution and its Reaction Mechanism

2022 ◽  
pp. 120465
Author(s):  
Jia-Ying Li ◽  
Rui Hu ◽  
Lili Shan ◽  
Zheng-Qian Liu ◽  
Sui-Qin Yang ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Electrochemical Process ◽  
Operating Conditions ◽  
Water Matrix

scholarly journals Performance of Iron-Functionalized Activated Carbon Catalysts (Fe/AC-f) on CWPO Wastewater Treatment

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 337
Author(s):  
Sara Mesa Medina ◽  
Ana Rey ◽  
Carlos Durán-Valle ◽  
Ana Bahamonde ◽  
Marisol Faraldos
Keyword(s):  
Wastewater Treatment ◽  
Activated Carbon ◽  
Landfill Leachate ◽  
Surface Composition ◽  
Treatment Plant ◽  
Reaction Medium ◽  
Pollutant Removal ◽  
Operating Conditions ◽  
Water Matrix ◽  
The Stability

Two commercial activated carbon were functionalized with nitric acid, sulfuric acid, and ethylenediamine to induce the modification of their surface functional groups and facilitate the stability of corresponding AC-supported iron catalysts (Fe/AC-f). Synthetized Fe/AC-f catalysts were characterized to determine bulk and surface composition (elemental analysis, emission spectroscopy, XPS), textural (N2 isotherms), and structural characteristics (XRD). All the Fe/AC-f catalysts were evaluated in the degradation of phenol in ultrapure water matrix by catalytic wet peroxide oxidation (CWPO). Complete pollutant removal at short reaction times (30–60 min) and high TOC reduction (XTOC = 80 % at ≤ 120 min) were always achieved at the conditions tested (500 mg·L−1 catalyst loading, 100 mg·L−1 phenol concentration, stoichiometric H2O2 dose, pH 3, 50 °C and 200 rpm), improving the results found with bare activated carbon supports. The lability of the interactions of iron with functionalized carbon support jeopardizes the stability of some catalysts. This fact could be associated to modifications of the induced surface chemistry after functionalization as a consequence of the iron immobilization procedure. The reusability was demonstrated by four consecutive CWPO cycles where the activity decreased from 1st to 3rd, to become recovered in the 4th run. Fe/AC-f catalysts were applied to treat two real water matrices: the effluent of a wastewater treatment plant with a membrane biological reactor (WWTP-MBR) and a landfill leachate, opening the opportunity to extend the use of these Fe/AC-f catalysts for complex wastewater matrices remediation. The degradation of phenol spiked WWTP-MBR effluent by CWPO using Fe/AC-f catalysts revealed pH of the reaction medium as a critical parameter to obtain complete elimination of the pollutant, only reached at pH 3. On the contrary, significant TOC removal, naturally found in complex landfill leachate, was obtained at natural pH 9 and half stoichiometric H2O2 dose. This highlights the importance of the water matrix in the optimization of the CWPO operating conditions.

scholarly journals Chemical–Electrochemical Process Concept for Lead Recovery from Waste Cathode Ray Tube Glass

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1546
Author(s):  
Árpád Imre-Lucaci ◽  
Melinda Fogarasi ◽  
Florica Imre-Lucaci ◽  
Szabolcs Fogarasi
Keyword(s):  
Flow Rate ◽  
Current Density ◽  
Complete Recovery ◽  
Electrochemical Process ◽  
Operating Conditions ◽  
General Effect ◽  
Optimal Operating ◽  
Recirculation Flow ◽  
Lead Recovery ◽  
Cathode Ray Tube

This paper presents a novel approach for the recovery of lead from waste cathode-ray tube (CRT) glass by applying a combined chemical-electrochemical process which allows the simultaneous recovery of Pb from waste CRT glass and electrochemical regeneration of the leaching agent. The optimal operating conditions were identified based on the influence of leaching agent concentration, recirculation flow rate and current density on the main technical performance indicators. The experimental results demonstrate that the process is the most efficient at 0.6 M acetic acid concentration, flow rate of 45 mL/min and current density of 4 mA/cm2. The mass balance data corresponding to the recycling of 10 kg/h waste CRT glass in the identified optimal operating conditions was used for the environmental assessment of the process. The General Effect Indices (GEIs), obtained through the Biwer Heinzle method for the input and output streams of the process, indicate that the developed recovery process not only achieve a complete recovery of lead but it is eco-friendly as well.

Electrochemical Disintegration of Activated Sludge Using Ti/RuO2 Anode

2014 ◽  
Vol 567 ◽  
pp. 44-49 ◽  
Author(s):  
Gan Chin Heng ◽  
Mohamed Hasnain Isa
Keyword(s):  
Current Density ◽  
Biological Treatment ◽  
Ph Value ◽  
Electrochemical Process ◽  
Operating Conditions ◽  
Electrolysis Time ◽  
Initial Ph ◽  
Electrode Surface Morphology ◽  
Alkaline Range ◽  
Sludge Concentration

Electrochemical process is one of the most effective methods to enhance sludge disintegration. In this study, Ti/RuO2 anodes were prepared by Pechini’s method and the electrode surface morphology was characterized by FESEM and EDAX. The effects of various operating conditions were investigated including initial pH value of sludge, sludge concentration, electrolysis time and current density. The study showed that the removal efficiencies of TS, VS, TSS and VSS increased with the increase of pH in the alkaline range, electrolysis time and current density but decreased with the increase of initial sludge concentration. The application of electrochemical process using Ti/RuO2 electrodes enhanced the sludge disintegration for possible subsequent biological treatment.

scholarly journals Towards molecular control of elementary reactions in zeolite catalysis by advanced molecular simulations mimicking operating conditions

2016 ◽  
Vol 6 (8) ◽  
pp. 2686-2705 ◽  
Author(s):  
Kristof De Wispelaere ◽  
Simon Bailleul ◽  
Veronique Van Speybroeck
Keyword(s):  
Reaction Mechanism ◽  
Reaction Temperature ◽  
Guest Molecule ◽  
Molecular Simulations ◽  
Operating Conditions ◽  
Molecular Control ◽  
Elementary Reactions ◽  
Zeolite Catalysis

Ingeniously selecting zeolite topology and acidity, reaction temperature and guest molecule loading enables tuning the reaction mechanism of zeolite-catalyzed methylation reactions.

scholarly journals Experimental and Modeling Investigation of CO3=/OH– Equilibrium Effects on Molten Carbonate Fuel Cell Performance in Carbon Capture Applications

2021 ◽  
Vol 9 ◽  
Author(s):  
Timothy A. Barckholtz ◽  
Heather Elsen ◽  
Patricia H. Kalamaras ◽  
Gabor Kiss ◽  
Jon Rosen ◽  
...  
Keyword(s):  
Carbon Capture ◽  
High Current Density ◽  
Electrochemical Process ◽  
Operating Conditions ◽  
Cell Performance ◽  
Molten Carbonate Fuel Cell ◽  
Average Error ◽  
Molten Carbonate ◽  
Fuel Cell Performance ◽  
Electrochemical Model

Molten Carbonate Fuel Cells (MCFCs) are used today commercially for power production. More recently they have also been considered for carbon capture from industrial and power generation CO2 sources. In this newer application context, our recent studies have shown that at low CO2/H2O cathode gas ratios, water supplements CO2 in the electrochemical process to generate power but not capture CO2. We now report the direct Raman observation of the underlying carbonate-hydroxide equilibrium in an alkali carbonate eutectic near MCFC operating conditions. Our improved electrochemical model built on the experimental equilibrium data adjusts the internal resistance terms and has improved the representation of the MCFC performance. This fundamentally improved model now also includes the temperature dependence of cell performance. It has been validated on experimental data collected in single cell tests. The average error in the simulated voltage is less than 4% even when extreme operating conditions of low CO2 concentration and high current density data are included. With the improvements, this electrochemical model is suitable for simulating industrial cells and stacks employed in a wide variety of carbon capture applications.

Degradation of Landfill Leachate by Combined Three-Dimensional Electrode and Electro-Fenton

2011 ◽  
Vol 347-353 ◽  
pp. 440-443 ◽  
Author(s):  
Yan Shi ◽  
Hai Chen Yu ◽  
Dan Yu Xu ◽  
Xian Qiang Zheng
Keyword(s):  
Reaction Mechanism ◽  
Electrochemical Oxidation ◽  
Landfill Leachate ◽  
Three Dimensional ◽  
Operating Conditions ◽  
Optimal Operating ◽  
Oxidation Technology ◽  
Iron Anode ◽  
Removal Efficiencies

Three-dimensional-electrode electro-Fenton is a newly electrochemical oxidation technology to treat landfill leachate. In contrast, the removal efficiencies of COD and color in DSA system are obviously higher than those in iron anode system and the organics can be degraded more thoroughly. Under the optimal operating conditions, the removal efficiencies of COD, NH3-N and color in landfill leachate by DSA system are up to 80.8% ,55.2% and 98.6％. Besides, the reaction mechanism of three-dimensional-electrode electro-Fenton is also discussed.

scholarly journals Solar Photocatalytic Degradation of Bisphenol A on Immobilized ZnO or TiO2

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Andreas Zacharakis ◽  
Efthalia Chatzisymeon ◽  
Vassilios Binas ◽  
Zacharias Frontistis ◽  
Danae Venieri ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Endocrine Disruptors ◽  
Treatment Time ◽  
Pure Water ◽  
Operating Conditions ◽  
Solar Irradiation ◽  
Water Matrix ◽  
Immobilized Catalyst ◽  
Low Concentrations ◽  
Simulated Solar Irradiation

The removal of bisphenol A (BPA) under simulated solar irradiation and in the presence of either TiO2or ZnO catalysts immobilized onto glass plates was investigated. The effect of various operating conditions on degradation was assessed including the amount of the immobilized catalyst (36.1–150.7 mg/cm2for TiO2and 0.5–6.8 mg/cm2for ZnO), initial BPA concentration (50–200 μg/L), treatment time (up to 90 min), water matrix (wastewater, drinking water, and pure water), the addition of H2O2(25–100 mg/L), and the presence of other endocrine disruptors in the reaction mixture. Specifically, it was observed that increasing the amount of immobilized catalyst increases BPA conversion and so does the addition of H2O2up to 100 mg/L. Moreover, BPA degradation follows first-order reaction kinetics indicating that the final removal is not practically affected by the initial BPA concentration. Degradation in wastewater is slower than that in pure water up to five times, implying the scavenging behavior of effluent’s constituents against hydroxyl radicals. Finally, the presence of other endocrine disruptors, such as 17α-ethynylestradiol, spiked in the reaction mixture at low concentrations usually found in environmental samples (i.e., 100 μg/L), neither affects BPA degradation nor alters its kinetics to a considerable extent.

A Novel Approach to Mechanism Reduction Optimization for an Aviation Fuel/Air Reaction Mechanism Using a Genetic Algorithm

2004 ◽  
Vol 128 (2) ◽  
pp. 255-263 ◽  
Author(s):  
L. Elliott ◽  
D. B. Ingham ◽  
A. G. Kyne ◽  
N. S. Mera ◽  
M. Pourkashanian ◽  
...  
Keyword(s):  
Genetic Algorithm ◽  
Reaction Mechanism ◽  
Reaction Rate ◽  
Flame Structure ◽  
Chemical Kinetic ◽  
Reaction Scheme ◽  
Operating Conditions ◽  
Aviation Fuel ◽  
Reduced Mechanism ◽  
Genetic Algorithm Approach

This study presents a novel multiobjective genetic-algorithm approach to produce a new reduced chemical kinetic reaction mechanism to simulate aviation fuel combustion under various operating conditions. The mechanism is used to predict the flame structure of an aviation fuel/O2∕N2 flame in both spatially homogeneous and one-dimensional premixed combustion. Complex hydrocarbon fuels, such as aviation fuel, involve large numbers of reaction steps with many species. As all the reaction rate data are not well known, there is a high degree of uncertainty in the results obtained using these large detailed reaction mechanisms. In this study a genetic algorithm approach is employed for determining new reaction rate parameters for a reduced reaction mechanism for the combustion of aviation fuel-air mixtures. The genetic algorithm employed incorporates both perfectly stirred reactor and laminar premixed flame data in the inversion process, thus producing an efficient reaction mechanism. This study provides an optimized reduced aviation fuel-air reaction scheme whose performance in predicting experimental major species profiles and ignition delay times is not only an improvement on the starting reduced mechanism but also on the full mechanism.

Sign in / Sign up

Export Citation Format

Share Document