Optimization of NO oxidation by H(2)O(2) thermal decomposition at moderate temperatures

H(2)O(2) was adopted to oxidize NO in simulated flue gas at 100–500°C. The effects of the H(2)O(2) evaporation conditions, gas temperature, initial NO concentration, H(2)O(2) concentration, and H(2)O(2):NO molar ratio on the oxidation efficiency of NO were investigated. The reason for the narrow NO oxidation temperature range near 500°C was determined. The NO oxidation products were analyzed. The removal of NOx using NaOH solution at a moderate oxidation ratio was studied. It was proven that rapid evaporation of the H(2)O(2) solution was critical to increase the NO oxidation efficiency and broaden the oxidation temperature range. the NO oxidation efficiency was above 50% at 300–500°C by contacting the outlet of the syringe needle and the stainless-steel gas pipe together to spread H(2)O(2) solution into a thin film on the surface of the stainless-steel gas pipe, which greatly accelerated the evaporation of H(2)O(2). The NO oxidation efficiency and the NO oxidation rate increased with increasing initial NO concentration. This method was more effective for the oxidation of NO at high concentrations. H(2)O(2) solution with a concentration higher than 15% was more efficient in oxidizing NO. High temperatures decreased the influence of the H(2)O(2) concentration on the NO oxidation efficiency. The oxidation efficiency of NO increased with an increase in the H(2)O(2):NO molar ratio, but the ratio of H(2)O(2) to oxidized NO decreased. Over 80% of the NO oxidation product was NO(2), which indicated that the oxidation ratio of NO did not need to be very high. An 86.7% NO removal efficiency was obtained at an oxidation ratio of only 53.8% when combined with alkali absorption.