Degradation of thiocyanate by electrochemical oxidation process in coke oven wastewater: Role of operative parameters and mechanistic study

Chemosphere ◽  
2020 ◽  
Vol 255 ◽  
pp. 127014 ◽  
Author(s):  
Ayşenur Turan ◽  
Ramazan Keyikoglu ◽  
Mehmet Kobya ◽  
Alireza Khataee
Keyword(s):  
Electrochemical Oxidation ◽  
Oxidation Process ◽  
Coke Oven ◽  
Mechanistic Study

scholarly journals Electrochemical oxidation induced intermolecular aromatic C-H imidation

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Xia Hu ◽  
Guoting Zhang ◽  
Lei Nie ◽  
Taige Kong ◽  
Aiwen Lei
Keyword(s):  
Electrochemical Oxidation ◽  
Aromatic Compounds ◽  
Oxidation Process ◽  
Cross Coupling ◽  
Radical Addition ◽  
Mechanistic Study ◽  
Transfer Event ◽  
Proton Coupled Electron Transfer ◽  
Anode Oxidation ◽  
Addition Pathway

AbstractThe dehydrogenative aryl C-H/N-H cross-coupling is a powerful synthetic methodology to install nitrogen functionalities into aromatic compounds. Herein, we report an electrochemical oxidation induced intermolecular cross-coupling between aromatics and sulfonimides with high regioselectivity through N-radical addition pathway under external-oxidant-free and catalyst-free conditions. A wide variety of arenes, heteroarenes, alkenes and sulfonimides are applicable scaffolds in this transformation. In addition, aryl sulfonamides or amines (aniline derivatives) can be obtained through different deprotection process. The cyclic voltammetry mechanistic study indicates that the N-centered imidyl radicals are generated via proton-coupled electron transfer event jointly mediated by tetrabutylammonium acetate and anode oxidation process.

scholarly journals Dynamics of Oxidation of Reduced Forms of CO2 under Electrochemical and Open-Сircuit Conditions on Polycrystalline Pt in H2CO3

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 274
Author(s):  
Alexander V. Smolin ◽  
Мikhail N. Mikhailov ◽  
Aleksey F. Gadzaov ◽  
Leonid M. Kustov
Keyword(s):  
Quantum Chemical ◽  
Preliminary Analysis ◽  
Oxidation Reaction ◽  
Density Functional ◽  
Oxidation Process ◽  
Open Circuit ◽  
Organic Substances ◽  
Oxidation Of Co ◽  
Reduced Forms

The problem of identifying correlations between catalytic and electrocatalytic processes is one of the fundamental problems of catalysis among “simple” organic substances, and the oxidation of CO and rCO2 is of great interest, since CO and CO2 are considered in pairs both during catalytic and electrocatalytic transformations. In the case of electrocatalysis, this analysis is important in the study of fuel cells. In this paper, we studied the correlation between the oxidation of reduced forms of CO2 (rCO2) under potentiodynamic-galvanoctatic electrochemical and open-circuit conditions of measurements on polycrystalline (pc)Pt in H2CO3. Periodic oscillations are revealed at the oxidation of Had and rCO2 on (pc)Pt. Quantum chemical calculations were carried out on the Pt13 cluster in order to identify the mechanisms of the rCO2 oxidation reaction. The correspondence in the energy parameters of the oxidation process of rCO2 under open-circuit conditions and electrochemical conditions is shown. The preliminary analysis of the system using density functional (DFT) calculations is carried out and the most stable systems that are based on Pt13 are found, namely rOH-Pt13-(CO)n, rOH-Pt13-(COH) and rOH-Pt13-(rCOOH). OH• species was chosen as the most likely candidate for the role of the oxidant for rCO2. Preliminary calculations for the expected reactions were carried out, and the optimal PES is revealed.

MECHANISTIC STUDY OF COLCHICINE’s ELECTROCHEMICAL OXIDATION

2015 ◽  
Vol 178 ◽  
pp. 624-630 ◽  
Author(s):  
Ede Bodoki ◽  
Ruxandra Chira ◽  
Valentin Zaharia ◽  
Robert Săndulescu
Keyword(s):  
Electrochemical Oxidation ◽  
Mechanistic Study

scholarly journals The role of a chemical loop in removal of hazardous contaminants from coke oven wastewater during its treatment

2019 ◽  
Vol 17 (1) ◽  
pp. 1288-1300
Author(s):  
Anna Kwiecińska-Mydlak ◽  
Marcin Sajdak ◽  
Katarzyna Rychlewska ◽  
Jan Figa
Keyword(s):  
Chemical Treatment ◽  
Treatment Process ◽  
Oxygen Demand ◽  
Coke Oven ◽  
Main Role ◽  
Biological Processes ◽  
Coal Processing ◽  
Wastewater Treatment Process ◽  
Iron Based

AbstractCoke oven liquor is one of the most contaminated liquid streams generated by the coal processing industry, thus its proper treatment and utilization is crucial for sustainable and environmentally neutral plant operation. The conventional wastewater treatment process comprises of chemical and biological processes. Within the current research the detailed role of chemical treatment is described. Commercially available iron-based coagulants (PIX100, PIX100COP, PIX113, PIX116) were tested to understand their removal efficiency and impact on the stream parameters. The influence of iron dose in the range of 300-500 mgFe/L on the process performance was also examined.It was found that the main role of chemical treatment was to bind toxicants harmful to activated sludge microorganisms, i.e. free and complex cyanides and sulphides. Among the tested iron-based conventional coagulants ferrous salts were more efficient than ferric salts. It was also observed that efficiency of the process strongly depended on wastewater properties (especially in regard to pH, which should be in the range of 9-10) and the coagulant selection needed to be done individually for a given wastewater type. The removal rates of particular contaminants were diversified and for free cyanides, complex cyanides and sulphides they were in the range of 23-91%, -156-77% and -357-98%, respectively. The expected, simultaneous removal of chemical oxygen demand (COD) during the treatment was not observed and even the parameter value increased after the process due to probable formation of compounds less vulnerable to oxidation.

Mechanistic Study of the Role of One-Component Resins in Rubber-to-Brass Bonding in Tires

2004 ◽  
Vol 77 (5) ◽  
pp. 891-913 ◽  
Author(s):  
Pankaj Y. Patil ◽  
William J. van Ooij
Keyword(s):  
Reaction Time ◽  
Secondary Ion Mass Spectrometry ◽  
Gel Permeation Chromatography ◽  
Mechanistic Study ◽  
Coated Steel ◽  
Adhesion Promoters ◽  
Steel Cords ◽  
Adhesion Performance ◽  
Secondary Ion

Abstract Adhesion between rubber and brass-coated steel cords is enhanced by using resins as adhesion promoters. Experiments were carried out using a squalene liquid rubber modeling approach to study the effect of resins on the chemistry of the vulcanization reaction. The formation of new intermediates during vulcanization and changes in chemical concentrations with reaction time was studied using Gel Permeation Chromatography (GPC) analysis of the reacted squalene mixtures. Also, the effect of presence of resins on the surface of sulfidized brass cords was studied by analyzing the adhesion layer's elemental composition using the Electron Dispersive X-ray Spectroscopy (EDX) and Secondary Ion Mass Spectrometry (SIMS) characterization techniques. The changes in surface morphology of the adhesion layer with reaction time was noted by taking micrographs using the Scanning Electron Microscopy (SEM) technique. In this paper, a new mechanism is proposed for the role of resins in the improvement of initial and aged adhesion performance between rubber and brass-coated steel tire cords.

scholarly journals The simultaneous removal of bisphenol A, manganese and ammonium from groundwater by MeOx: The role of chemical catalytic oxidation for bisphenol A

2021 ◽  
Author(s):  
Yingming Guo ◽  
Ben Ma ◽  
Jianxiong Huang ◽  
Jing Yang ◽  
Ruifeng Zhang
Keyword(s):  
Oxide Film ◽  
Bisphenol A ◽  
Dissolved Oxygen ◽  
Oxidation Process ◽  
Pilot Scale ◽  
Simultaneous Removal ◽  
Chemical Forms ◽  
Synergy Effect ◽  
Iron And Manganese

Abstract The iron and manganese oxide filter film (MeOx) were used to research the simultaneous removal of bisphenol A (BPA), manganese (Mn2+) and ammonium (NH4+) in a pilot-scale filter system. We found that 0.52 mg/L of BPA could be removed while consuming 5.44 mg/L of dissolved oxygen (DO). Since the oxidation process of NH4+ and BPA both consume the DO in water, the presence of NH4+ can hinder the removal of BPA. The presence of Mn2+ in water had a synergy effect on the BPA removal. The filter film was characterized by SEM, XRD and XPS. Some substances were generated to block the pores of the oxide film, and a small amount of film was found to crack and fall off. The elemental composition of C and O were both increased by about 9%, the composition of Mn was decreased from 63.48% to 44.55%, and the reduced manganese substance might affect the activity of the oxide film. The main chemical forms of MeOx are Mn6O12·3H2O, MnFe2O4 or Mn3O4. The decrease in the removal efficiency of BPA was mainly due to the C-containing intermediate [−CH2C − H(OH)]n covering the surface of the oxide film and blocking the pore size of the film.

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