Efficient degradation of phenol by electrooxidation process at boron-doped diamond anode system

Abstract

The rapid increase in global population and industrialization has led to increased environmental pollution, primarily due to insufficient treatment technologies and the depletion of freshwater resources. This research investigates the impact of the electrooxidation (EO) process using Boron Doped Diamond (BDD) anode on phenol degradation, energy consumption, total operating costs, and anode efficiency. The study was carried out on different current densities (j = 50-200 A/m2), initial pH (3.6-9.6), initial phenol concentration (Ci = 100-800 mg/L), and supporting electrolyte concentration (SEc = 2-6 g NaCl/L). The phenol removal efficiency under optimum conditions (anode = BDD, j = 200 A/m2, initial pH = 7.6, Cphenol = 100 mg/L, and SEc = 4 g NaCl/L) was determined to be 100% after 50 min of EO reaction time. However, the energy consumption and total operating cost under these conditions were 12.7 kWh/m3 (420 kWh/kg phenol) and 0.99 $/m3 (7.88 $/kg phenol), respectively. Moreover, BDD anode efficiencies were calculated as 6.39, 3.47, and 1.74 g phenol/Ahm2 at current densities of 50, 100, and 200 A/m2, respectively. Consequently, the EO process is a more cost-effective treatment approach for efficient phenol removal from an aqueous solution.