Wastewater Treatment Using a Photoelectrochemical Oxidation Process for the Coffee Processing Industry Optimization of Chemical Oxygen Demand (COD) Removal Using Response Surface Methodology

Abstract

e elimination of organic compounds in co ee processing e uent utilizing electrochemical oxidation (ECO) as well as a combination of electrochemical oxidation (ECO) and ultraviolet and hydrogen peroxide (UV/H2O2) was explored. en, the percentage reduction of chemical oxygen demand (COD) was investigated. e e ect of di erent experimental factors such as solution pH, sodium chloride (NaCl) concentration, calcium chloride (CaCl2) concentration, electric current, electrolysis du ration, and hydrogen peroxide dosage on the percent removal e ciency of the hybrid electrochemical oxidation (ECO) with the ultraviolet and hydrogen peroxide (UV/H2O2) process has been investigated. e response surface methodology (RSM) based on central composite design (CCD) was used to organize the trial runs and optimize the results. e hybrid electrochemical oxidation (ECO) with the ultraviolet and hydrogen peroxide (UV/H2O2) process removed 99.61% of the chemical oxygen demand (COD) with a low power usage of 1.12 kWh/m3 compared to the other procedures, according to the experimental data analysis. ese ndings were obtained with a pH of 7, a current of 0.40 A, 1.5 g of CaCl2, and a total electrolysis period of 40 minutes. When it came to eliminating organic compounds from co ee manufacturing e uent, CaCl2 outperformed NaCl. Analysis of variance (ANOVA) with 95% con dence limits was used to examine the signi cance of independent variables and their interactions.