Izabela Dobrosz-Gómez, Harold N. Ibarra-Taquez, Miguel-Ángel Gómez-García
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引用次数: 0
Abstract
In this study, an industrial wastewater from instant coffee production was treated by electrocoagulation (EC). The effect of various EC operating parameters, such as electrode type, current density, support electrolyte concentration and stirring velocity, were investigated to determine the optimal operating EC conditions. The scope of electrocoagulation (EC) was assessed, in environmental and economic terms, for the treatment of industrial wastewater originated from the production of instant coffee. The evaluation included the effect of EC operating factors (electrode type, current density, supporting electrolyte concentration and stirring velocity) on Color removal, COD and TOC degradation, toxicity, molecular weight distribution, as well as the total operating cost. The following optimal operating conditions were established through a series of preliminary experiments, a Box-Behnken design of experiments, Response Surface Methodology application, and multi-objective optimization analysis: the pair of Fe (anode)-stainless steel (cathode) electrodes, supporting electrolyte = 1.78 g of NaCl/L; current density = 150 A/m2; electrode gap = 3 mm; stirring velocity = 350 RPM; and pH0 = 4.7 (that of raw industrial effluent). Finally, the kinetic study allowed defining the electrolysis operation time of ca. 180 min required to comply with the maximum permissible discharge limits for the production of instant coffee the discharge of soluble coffee effluents, in terms of COD concentration, established by current Colombian legislation. The EC reached ca. 97% decolorization, as well as 72% and 65% of COD and TOC removal degradation, respectively, with total operating costs of 6.26 USD/m3. This yielded an oxidized (COS = 2.87), biocompatible (BOD5/COD = 0.437) and non-toxic effluent, free of contaminants with molecular weight > 30 kDa. The EC appeared as an effective alternative for the treatment of industrial wastewater from the production of instant coffee within the framework of different Sustainable Development Goals (number 6 (Clean water and sanitation), number 7 (Clean and affordable energy), number 9 (Industry, innovation and infrastructure) and 13 (Climate action)).
期刊介绍:
The Journal of Solid State Electrochemistry is devoted to all aspects of solid-state chemistry and solid-state physics in electrochemistry.
The Journal of Solid State Electrochemistry publishes papers on all aspects of electrochemistry of solid compounds, including experimental and theoretical, basic and applied work. It equally publishes papers on the thermodynamics and kinetics of electrochemical reactions if at least one actively participating phase is solid. Also of interest are articles on the transport of ions and electrons in solids whenever these processes are relevant to electrochemical reactions and on the use of solid-state electrochemical reactions in the analysis of solids and their surfaces.
The journal covers solid-state electrochemistry and focusses on the following fields: mechanisms of solid-state electrochemical reactions, semiconductor electrochemistry, electrochemical batteries, accumulators and fuel cells, electrochemical mineral leaching, galvanic metal plating, electrochemical potential memory devices, solid-state electrochemical sensors, ion and electron transport in solid materials and polymers, electrocatalysis, photoelectrochemistry, corrosion of solid materials, solid-state electroanalysis, electrochemical machining of materials, electrochromism and electrochromic devices, new electrochemical solid-state synthesis.
The Journal of Solid State Electrochemistry makes the professional in research and industry aware of this swift progress and its importance for future developments and success in the above-mentioned fields.