Degradation of acetaminophen by Fenton and electro-Fenton processes in aerator reactor

This study investigated the degradation of acetaminophen (ACTP) in the Fenton and electro-Fenton processes in an aerator reactor. The influences of important parameters on acetaminophen degradation were studied and described in details. The experimental results show that the Fenton and electro-Fenton processes had maximum ACTP degradation efficiencies of 99% and 100%, respectively. The ACTP degradation efficiency of Fenton process and electro-Fenton process were apparently increased at pH 2 and 4, respectively; ACTP degradation efficiency increased 72% at pH 2 in the Fenton process and 74% at pH 4 in the electro-Fenton process when fixed H2O2 dosage (15 mM) and Fe2+ dosage was increased from 0.01 to 0.1 mM. The Box–Behnken design results indicated that the relative effects of the studied parameters on ACTP degradation in Fenton and electro-Fenton processes were Fe2+ > H2O2 > pH. The initial rate of ACTP degradation (r) and ACTP degradation efficiency in the electro-Fenton process were apparently higher than those in the Fenton process at pH 2, as a high H2O2-to-Fe2+ molar ratio (1500) was used. The COD and TOC obtained by electro-Fenton process were 12% and 65% higher, respectively, than those in the Fenton process.

► An electro-Fenton reactor with an aerator and a sludge outlet was used.
► The effects of the studied parameters on ACTP degradation were Fe2+ > H2O2 > pH.
► The COD and TOC obtained by electro-Fenton process were 12% and 65% higher, respectively, than those in Fenton process.