title: The Box-Benkhen experimental design for the optimization of the electrocatalytic treatment of wastewaters with high concentrations of phenol and organic matter.
abstract: 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.
authors.affiliation: GIPAB: Grupo de Investigación en Procesos Ambientales y Biotecnológicos, Departamento de Ingeniería de Procesos, Universidad EAFIT, Carrera 49 #7 sur 50, Medellín, Colombia. egil@eafit.edu.co
authors.forename: Edison
authors.initials: E
authors.lastname: GilPavas
authors.forename: Alejandra
authors.initials: A
authors.lastname: Betancourt
authors.forename: Mónica
authors.initials: M
authors.lastname: Angulo
authors.forename: Izabela
authors.initials: I
authors.lastname: Dobrosz-Gómez
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: Gómez-García
mesh_terms: D002384:Catalysis; D004563:Electrochemistry; D004566:Electrodes; D004867:Equipment Design; D006108:Graphite; D007700:Kinetics; D009930:Organic Chemicals / Q000032:analysis*; D010084:Oxidation-Reduction; D010636:Phenols / Q000032:analysis*; D014025:Titanium; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*
chemical_list: D009930:Organic Chemicals; D010636:Phenols; D006108:Graphite; D014025:Titanium