The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
P.h. Pfromm - One of the best experts on this subject based on the ideXlab platform.
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Recycling wood Pulping chemicals by molten salt electrolysis: cyclic voltammetry of mixtures containing Na_2CO_3 and Na_2SO_4
Journal of Applied Electrochemistry, 2002Co-Authors: R. Wartena, J. Winnick, P.h. PfrommAbstract:We are investigating a novel electrochemical pathway for efficient recycling of inorganic chemicals from the Kraft Pulping Process. To analyse this Process, cyclic voltammetry was conducted on molten salts containing sodium carbonate, or sodium carbonate and sodium sulfate on gold and nickel/nickel oxide electrodes. Pure sodium carbonate at 860 °C was determined to exhibit oxidation to carbon dioxide and oxygen. Electrochemical reduction proceeded to both sodium metal and to sodium oxide and either carbon or carbon monoxide. A mixture with a 2.36:1 molar ratio of sodium carbonate to sodium sulfate at 860 °C was investigated where the anode again displayed carbonate oxidation. The cathode reactions are the reduction of sulfate ions to form sulfide and oxide ions and carbonate reduction to oxide ions and carbon monoxide. Separated cell operation to avoid oxide ion oxidation appears necessary according to the cyclic voltammetry. Nickel oxide was found to be a stable anode material in a sodium carbonate molten salt. This paper, based on cyclic voltammetry results of oxide ion production, is the first step towards a technical electrolysis Process for recausticizing of molten smelt for the Kraft Pulping Process.
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Recycling wood Pulping chemicals by molten salt electrolysis: cyclic voltammetry of mixtures containing Na2CO3 and Na2SO4
Journal of Applied Electrochemistry, 2002Co-Authors: R. Wartena, J. Winnick, P.h. PfrommAbstract:We are investigating a novel electrochemical pathway for efficient recycling of inorganic chemicals from the Kraft Pulping Process. To analyse this Process, cyclic voltammetry was conducted on molten salts containing sodium carbonate, or sodium carbonate and sodium sulfate on gold and nickel/nickel oxide electrodes. Pure sodium carbonate at 860 °C was determined to exhibit oxidation to carbon dioxide and oxygen. Electrochemical reduction proceeded to both sodium metal and to sodium oxide and either carbon or carbon monoxide. A mixture with a 2.36:1 molar ratio of sodium carbonate to sodium sulfate at 860 °C was investigated where the anode again displayed carbonate oxidation. The cathode reactions are the reduction of sulfate ions to form sulfide and oxide ions and carbonate reduction to oxide ions and carbon monoxide. Separated cell operation to avoid oxide ion oxidation appears necessary according to the cyclic voltammetry. Nickel oxide was found to be a stable anode material in a sodium carbonate molten salt. This paper, based on cyclic voltammetry results of oxide ion production, is the first step towards a technical electrolysis Process for recausticizing of molten smelt for the Kraft Pulping Process.
R. Wartena - One of the best experts on this subject based on the ideXlab platform.
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Recycling wood Pulping chemicals by molten salt electrolysis: cyclic voltammetry of mixtures containing Na_2CO_3 and Na_2SO_4
Journal of Applied Electrochemistry, 2002Co-Authors: R. Wartena, J. Winnick, P.h. PfrommAbstract:We are investigating a novel electrochemical pathway for efficient recycling of inorganic chemicals from the Kraft Pulping Process. To analyse this Process, cyclic voltammetry was conducted on molten salts containing sodium carbonate, or sodium carbonate and sodium sulfate on gold and nickel/nickel oxide electrodes. Pure sodium carbonate at 860 °C was determined to exhibit oxidation to carbon dioxide and oxygen. Electrochemical reduction proceeded to both sodium metal and to sodium oxide and either carbon or carbon monoxide. A mixture with a 2.36:1 molar ratio of sodium carbonate to sodium sulfate at 860 °C was investigated where the anode again displayed carbonate oxidation. The cathode reactions are the reduction of sulfate ions to form sulfide and oxide ions and carbonate reduction to oxide ions and carbon monoxide. Separated cell operation to avoid oxide ion oxidation appears necessary according to the cyclic voltammetry. Nickel oxide was found to be a stable anode material in a sodium carbonate molten salt. This paper, based on cyclic voltammetry results of oxide ion production, is the first step towards a technical electrolysis Process for recausticizing of molten smelt for the Kraft Pulping Process.
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Recycling wood Pulping chemicals by molten salt electrolysis: cyclic voltammetry of mixtures containing Na2CO3 and Na2SO4
Journal of Applied Electrochemistry, 2002Co-Authors: R. Wartena, J. Winnick, P.h. PfrommAbstract:We are investigating a novel electrochemical pathway for efficient recycling of inorganic chemicals from the Kraft Pulping Process. To analyse this Process, cyclic voltammetry was conducted on molten salts containing sodium carbonate, or sodium carbonate and sodium sulfate on gold and nickel/nickel oxide electrodes. Pure sodium carbonate at 860 °C was determined to exhibit oxidation to carbon dioxide and oxygen. Electrochemical reduction proceeded to both sodium metal and to sodium oxide and either carbon or carbon monoxide. A mixture with a 2.36:1 molar ratio of sodium carbonate to sodium sulfate at 860 °C was investigated where the anode again displayed carbonate oxidation. The cathode reactions are the reduction of sulfate ions to form sulfide and oxide ions and carbonate reduction to oxide ions and carbon monoxide. Separated cell operation to avoid oxide ion oxidation appears necessary according to the cyclic voltammetry. Nickel oxide was found to be a stable anode material in a sodium carbonate molten salt. This paper, based on cyclic voltammetry results of oxide ion production, is the first step towards a technical electrolysis Process for recausticizing of molten smelt for the Kraft Pulping Process.
Pedram Fatehi - One of the best experts on this subject based on the ideXlab platform.
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fly ash based adsorbent for treating bleaching effluent of Kraft Pulping Process
Separation and Purification Technology, 2018Co-Authors: Pedram FatehiAbstract:Abstract The bleaching operation of a Kraft Pulping Process generates a large amount of effluents with high organic loads. The affinity of biomass-based fly ash as a low-cost adsorbent for reducing lignin concentration, chemical oxygen demand (COD) and turbidity of the bleaching effluents prior to a biological treatment Process was studied in this work. The results showed that the optimized conditions for obtaining the maximum removals of lignin (81.6%) and COD (67.9%) were the fly ash dosage of 6 wt% in the effluent and the treatment time of 30 min and temperature of 30 °C. The results also showed that the settling rate of the fly ash in fly ash/effluent suspension systems increased as fly ash dosage increased. Charge neutralization played a key role at a low fly ash dosage (less than 2 wt%) for removing lignocellulosic flocs smaller than 10 µm, while complexion of small flocs to larger ones (with the size of 30–500 µm) occurred at the higher fly ash dosage in the effluent. Coagulation and adsorption were the main phenomena for the removals of COD, lignin and turbidity at a higher fly ash dosage and a prolonged treatment time.
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a Process for isolating lignin of pre hydrolysis liquor of Kraft Pulping Process based on surfactant and calcium oxide treatments
Biochemical Engineering Journal, 2012Co-Authors: Pedram Fatehi, Huining Xiao, Yonghao NiAbstract:Abstract Hemicelluloses present in the pre-hydrolysis liquor (PHL) of the Kraft-based dissolving pulp production Process can potentially be converted into value-added products such as ethanol and xylitol. However, the lignin present in the PHL is an inhibitor of fermentation Processes, and thus should be isolated from the PHL prior to fermentation. In this study, a new Process was proposed for isolating the lignin of PHL by overliming and surfactant treatment. The fundamentals associated with the interactions of lignin, surfactants and calcium hydroxide were discussed. In the experimental part of this work, three different cationic surfactants were applied to industrially produced PHL, and the most effective one, dodecyltrimethyl ammonium chloride (DTAC), was selected for further analysis. The optimum dosage of 0.3% DTAC/PHL was identified via turbidity and particle size analyses. Additionally, overliming via CaO treatment resulted in removing 36.1% lignin and 23% hemicelluloses. Overliming followed by the DTAC treatment was more effective than the DTAC treatment followed by overliming in removing lignin. In the former, the maximum removals of 43.6% lignin and 27% hemicelluloses were obtained. The formation of lignocelluloses/surfactant complexes was confirmed by means of a Fourier transform infrared spectroscopy (FTIR) and thermo gravimetric analyzer (TGA).
Ana Lea Cukierman - One of the best experts on this subject based on the ideXlab platform.
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potentiality of lignin from the Kraft Pulping Process for removal of trace nickel from wastewater effect of demineralisation
Bioresource Technology, 2009Co-Authors: M Betancur, P R Bonelli, Jorge A Velasquez, Ana Lea CukiermanAbstract:Abstract An industrial raw Kraft lignin was investigated to ascertain its potential use for removal of trace Ni(II) ion from wastewater by using dilute solutions (0.34–1.7 mM) as models. The effect of demineralisation on its metal sorption ability was examined by employing acid pre-treated samples. Under fixed pre-established equilibrium conditions, the raw lignin exhibited a lower effectiveness than the demineralised one, with the latter attaining an almost complete removal of Ni(II) ions. For both lignins, sorption kinetics was properly described by a pseudo-second order rate model. Equilibrium isotherms were also determined and adequately represented by conventional two-parameter models. The higher nickel sorption capacity for the demineralised lignin compared to the raw sample was consistent with enhancements in the negative magnitude of zeta potential, sodium sorption capacity, and content of phenolic hydroxyl groups occasioned by the acid pre-treatment. Accordingly, demineralisation appears as a readily convenient strategy to improve the behaviour of industrial Kraft lignin for potential use as a biosorbent of trace nickel from polluted water.
J. Winnick - One of the best experts on this subject based on the ideXlab platform.
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Recycling wood Pulping chemicals by molten salt electrolysis: cyclic voltammetry of mixtures containing Na_2CO_3 and Na_2SO_4
Journal of Applied Electrochemistry, 2002Co-Authors: R. Wartena, J. Winnick, P.h. PfrommAbstract:We are investigating a novel electrochemical pathway for efficient recycling of inorganic chemicals from the Kraft Pulping Process. To analyse this Process, cyclic voltammetry was conducted on molten salts containing sodium carbonate, or sodium carbonate and sodium sulfate on gold and nickel/nickel oxide electrodes. Pure sodium carbonate at 860 °C was determined to exhibit oxidation to carbon dioxide and oxygen. Electrochemical reduction proceeded to both sodium metal and to sodium oxide and either carbon or carbon monoxide. A mixture with a 2.36:1 molar ratio of sodium carbonate to sodium sulfate at 860 °C was investigated where the anode again displayed carbonate oxidation. The cathode reactions are the reduction of sulfate ions to form sulfide and oxide ions and carbonate reduction to oxide ions and carbon monoxide. Separated cell operation to avoid oxide ion oxidation appears necessary according to the cyclic voltammetry. Nickel oxide was found to be a stable anode material in a sodium carbonate molten salt. This paper, based on cyclic voltammetry results of oxide ion production, is the first step towards a technical electrolysis Process for recausticizing of molten smelt for the Kraft Pulping Process.
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Recycling wood Pulping chemicals by molten salt electrolysis: cyclic voltammetry of mixtures containing Na2CO3 and Na2SO4
Journal of Applied Electrochemistry, 2002Co-Authors: R. Wartena, J. Winnick, P.h. PfrommAbstract:We are investigating a novel electrochemical pathway for efficient recycling of inorganic chemicals from the Kraft Pulping Process. To analyse this Process, cyclic voltammetry was conducted on molten salts containing sodium carbonate, or sodium carbonate and sodium sulfate on gold and nickel/nickel oxide electrodes. Pure sodium carbonate at 860 °C was determined to exhibit oxidation to carbon dioxide and oxygen. Electrochemical reduction proceeded to both sodium metal and to sodium oxide and either carbon or carbon monoxide. A mixture with a 2.36:1 molar ratio of sodium carbonate to sodium sulfate at 860 °C was investigated where the anode again displayed carbonate oxidation. The cathode reactions are the reduction of sulfate ions to form sulfide and oxide ions and carbonate reduction to oxide ions and carbon monoxide. Separated cell operation to avoid oxide ion oxidation appears necessary according to the cyclic voltammetry. Nickel oxide was found to be a stable anode material in a sodium carbonate molten salt. This paper, based on cyclic voltammetry results of oxide ion production, is the first step towards a technical electrolysis Process for recausticizing of molten smelt for the Kraft Pulping Process.
