Electrochemical and sonochemical advanced oxidation processes applied to tartrazine removal. Influence of operational conditions and aqueous matrix

Tartrazine degradation was investigated by electrochemical and sonochemical oxidation processes. Anodic carried out using boron-doped diamond (BDD) electrodes. The influence of current density dye initial concentration on the removal tartrazine from water analyzed. experimental results indicate that total obtained, Chemical Oxygen Demand (COD) Total Organic Carbon (TOC) removals up to 94.4% 72.8% were achieved, respectively. To optimize process, pollutant percentage, kinetic rate constant, TOC efficiency chosen as target variables. Moreover, experiments at a high-frequency range cavitation (up 1 MHz) performed establish three different operating variables, namely ultrasound frequency (0.5–1.1 MHz), power (2.0–26.6 W ⋅L−1), pulse-stop ratio (5:1–1:1). process also analyzed in terms kinetics energy costs. resulted be times faster for process. However, calculated costs very similar, least long treatment times. Finally, aqueous matrices investigated. According results, natural occurrence chloride and/or nitrate ions strongly conditions although 90% achieved within first 50 min treatment.