Removal of Carbon Monoxide from Simulated Flue Gas Using Two New Fenton Systems: Mechanism and Kinetics

摘要

Two novel removal processes of carbon monoxide using two new Fenton systems (i.e., Cu2+/Fe2+ and Mn2+/Fe2+ coactivated H2O2 systems) were developed. The effect of several process parameters (concentrations of H2O2, Fe2+, Cu2+, and Mn2+, reagent pH value, solution temperature, and simulated flue gas components) on CO removal was studied in a bubbling reactor. The mechanism and kinetics of CO removal were also revealed. Results show that adding Cu2+ or Mn2+ obviously enhances the removal process of CO in new Fenton systems. The measured results of free radical yield demonstrate' that the enhancing role is derived from producing more-OH (they are produced due to the synergistic activation role of Cu2+/Fe2+ or Mn2+/Fe2+ in new Fenton systems. The removal efficiency of CO is raised by increasing concentrations of Fe2+, Cu2+, and Mn2+ and is reduced by raising concentrations of CO, NO, and SO2. Increasing H2O2 concentration, reagent pH, and solution temperature demonstrates a dual impact on CO absorption. Three oxidation pathways are found to be responsible for CO removal in new Fenton systems. Results of mass-transfer reaction kinetics reveal that CO removal processes are located in a fast-speed reaction kinetics region (the CO removal process is controlled by the mass transfer rate).