A model for electrochemical insertion limited by a phase transition process - eilpt

This paper deals with electrochemical insertion into a cathodic material. New results on modeling of the influence of a solid phase transformation on the shape of voltamograms are presented. The original experiments concern the insertion of sodium into carbon during the cathodic reduction of molten NaF at 1020 °C, but in the present manuscript emphasis on the theoretical aspects of the work is put. Phase transformations during electrochemical insertion are taken into account, with various values for parameters such as the thermodynamic biphase equilibrium potential, the compared diffusion and phase transformation kinetics, and the electrode thickness. The voltamograms calculated present very specific features; some of them have already been observed experimentally in literature

Slaughterhouse Wastewater Treatment by Combined Chemical Coagulation and Electrocoagulation Process

Slaughterhouse wastewater contains various and high amounts of organic matter (e.g., proteins, blood, fat and lard). In order to produce an effluent suitable for stream discharge, chemical coagulation and electrocoagulation techniques have been particularly explored at the laboratory pilot scale for organic compounds removal from slaughterhouse effluent. The purpose of this work was to investigate the feasibility of treating cattle-slaughterhouse wastewater by combined chemical coagulation and electrocoagulation process to achieve the required standards. The influence of the operating variables such as coagulant dose, electrical potential and reaction time on the removal efficiencies of major pollutants was determined. The rate of removal of pollutants linearly increased with increasing doses of PACl and applied voltage. COD and BOD5 removal of more than 99% was obtained by adding 100 mg/L PACl and applied voltage 40 V. The experiments demonstrated the effectiveness of chemical and electrochemical techniques for the treatment of slaughterhouse wastewaters. Consequently, combined processes are inferred to be superior to electrocoagulation alone for the removal of both organic and inorganic compounds from cattle-slaughterhouse wastewater

Electro-Fenton catalyzed with magnetic chitosan beads for the removal of Chlordimeform insecticide

International audienceThe degradation of chlordimeform (CDM) has been investigated by a heterogeneous electro-Fenton process involving magnetite supported chitosan beads (Fe3O4-Cs) as catalyst. The catalyst was prepared by dropwise addition of an acidic chitosan-metal salts solution into sodium hydroxide precipitation bath. SEM, XRD and FTIR analysis were used to characterize the catalysts. The effect of experimental parameters, such as the current intensity, the amount of iron on chitosan beads, the concentration of the catalyst and the initial pH on the pollutant removal rate was investigated. The optimal conditions for the degradation of 37.5 mg L−1 initial CDM concentration were achieved at an applied cathodic current of −5 mA, using 0.5 g L−1 of magnetic chitosan beads (with an average iron amount of 0.104 mmol) and at pH = 3. Under these conditions, CDM was effectively removed within 30 min with 80% of NPOC removal after 6 h of treatment. The reaction followed a pseudo-first order kinetic equation. The adsorption test on the chitosan beads (with and without iron) demonstrated that the insecticide removal was solely induced by heterogeneous electro-Fenton treatment with Fe3O4-CS beads. In addition, the reusability of this catalyst was effectively demonstrated. Finally, LC–MS analysis allowed the proposal of a plausible degradation route