Use of a pulsed high-voltage discharge for removal of organic compounds in aqueous solution

TLDR

The study used a pulsed‑streamer corona discharge to investigate phenol removal, examining parameter effects, intermediate and final byproducts, and measuring CO₂ emission to elucidate the reaction mechanism. The pulsed‑streamer corona discharge effectively destroyed phenol, achieving 83 % TOC removal without oxygen bubbling and 86 % with bubbling, with intermediate products (hydroquinone, pyrocatechol, 1,4‑benzoquinone) disappearing at longer residence times.

Abstract

Results obtained using a pulsed-streamer corona discharge for organic compound removal are reported in this investigation. The removal of phenol and the effects of various parameters on the removal efficiency were studied. The intermediate products and final byproducts were also studied. It was found that the organic contaminants in aqueous solution could be destroyed effectively by the pulsed-streamer corona discharge and that the organic compound removal was greatly influenced by gas injection (bubbling). In addition, a preliminary study of the reaction mechanism was performed. Byproducts were determined for phenol removal. The main intermediate products produced by the pulsed-voltage discharge during the treatment process were hydroquinone, pyrocatechol and 1,4-benzoquinone. These intermediate products disappeared when the residence time was increased. By analysing the total carbon content of the treated phenol solution, it was found that 83% of the total organic carbon was removed without oxygen bubbling and 86% was removed with oxygen bubbling. Carbon dioxide emitted in the gas phase was measured by an absorption method.