Steam plasma jet treatment of phenol in aqueous solution at atmospheric pressure

Abstract

Summary form only given. Steam plasma jet (SPJ) was generated by phenol aqueous solution introduced into an original water plasma torch as plasma forming gas, which outflowed into phenol aqueous solution to conduct oxidation degradation of organic pollutants in aqueous solutions. The experimental results indicated that the phenol was not only rapidly decomposed in thermal plasma jet, but also degraded in phenol aqueous solution due to high concentration hydroxyl radicals. In addition, the outflow of high-velocity jet with dissociated aqueous phenol solution into the treated aqueous solution results in high rates of mass transfer processes, which were beneficial to the active species to liquid and their subsequent participation in chemical reactions with the liquid-phase organic pollutants. The main intermediates of phenol decomposition were pyrocatechol, hydroquinone, maleic acid, butanedioic acid and muconic acid in liquid, which were eventually degraded into CO 2 and H 2 O. The major gaseous effluence products were H 2 , CO and CO 2 . As a result, phenol was not only decomposed by the active hybrid modes, but also converted into resource (syngas), and the energy efficiencies significantly increased from (1.6–1.8)×10−10 to (4.8–8.0)×10−8 mol J−1 with the initial concentration of phenol increased from 0.5 to 50.0 g L−1. This paper highlighted the application of SPJ technology in high concentration of organic polluted wastewater treatment in environmental pollution management.