The Box-Benkhen experimental design for the optimization of the electrocatalytic treatment of wastewaters with high concentrations of phenol and organic matter.


In this work, the Box-Benkhen experimental Design (BBD) was applied for the optimization of the parameters of the electrocatalytic degradation of wastewaters resulting from a phenolic resins industry placed in the suburbs of Medellin (Colombia). The direct and the oxidant assisted electro-oxidation experiments were carried out in a laboratory scale batch cell reactor, with monopolar configuration, and electrodes made of graphite (anode) and titanium (cathode). A multifactorial experimental design was proposed, including the following experimental variables: initial phenol concentration, conductivity, and pH. The direct electro-oxidation process allowed to reach ca. 88% of phenol degradation, 38% of mineralization (TOC), 52% of Chemical Oxygen Demand (COD) degradation, and an increase in water biodegradability of 13%. The synergetic effect of the electro-oxidation process and the respective oxidant agent (Fenton reactant, potassium permanganate, or sodium persulfate) let to a significant increase in the rate of the degradation process. At the optimized variables values, it was possible to reach ca. 99% of phenol degradation, 80% of TOC and 88% of COD degradation. A kinetic study was accomplished, which included the identification of the intermediate compounds generated during the oxidation process.


Palabras clave

Biodegradation, Chemical oxygen demand, Chemicals removal (water treatment), Degradation, Design, Graphite electrodes, Optimization, Oxidants, Oxidation resistance, Oxygen, Phenolic resins, Phenols, Potassium, Reaction intermediates, Resins, Sodium, Statistics, Titanium, Wastewater, Wastewater treatment, Batch cells, Colombia, Degradation process, Electro-oxidation process, Electrocatalytic, Experimental design, High concentration, Intermediate compound, Kinetic study, Laboratory scale, Organic matter, Oxidation process, Phenol concentration, Phenol degradation, Potassium permanganate, Sodium persulfate, Synergetic effect, Anodic oxidation, graphite, organic matter, permanganate potassium, phenol, resin, titanium, biodegradation, catalysis, chemical oxygen demand, electrode, experimental design, mineralization, optimization, organic matter, oxidant, oxidation, pH, phenol, reaction kinetics, resin, suburban area, titanium, wastewater, water treatment, biodegradability, chemical oxygen d