This study employed an electrochemical process to eliminate formaldehyde from contaminated air streams. Various factors that influence the process, including electrode material, inter-electrode distance, air injection site, applied voltage, electrical power, current density, pH, reaction time, electrolyte type, concentration, and formaldehyde's initial concentration were investigated. Findings revealed optimal percentage decrease in concentration (χ), reaching 100 %, using aluminum (Al) electrodes with a 1 cm gap between them. Potassium Persulfate (PP) was found to have superior χ compared to sodium thiosulfate (STH). Regarding the air injection site, the higher χ was noted at the cathode (98.9 ± 0.85 %) than at the anode (95.2 ± 0.99 %). Efficiency escalated from 85.1 % at 7.5 volts to 100 % at 15 volts and, for current density, from 89.18 % at 0.042 amps to 100 % at 0.159 amps. Conversely, efficiency for air flow diminished from 100 % at 0.1 l/min to 27.32 ± 2.7 % at 4.4 l/min. Additional factors were also explored, including removing formaldehyde in the reactor's liquid phase and mineralization. Outcomes suggest that formaldehyde reacts with water, eventually transforming into carbon dioxide. Moreover, the reaction kinetics for both electrolytes demonstrated a tendency toward a second-order kinetic model.
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