Reaction performance study on denitration in aqueous solution of the dual oxidant (H₂O₂/S₂)

Abstract

The reaction performance study on NO removal by using the dual oxidant (H 2 O 2 /S 2 O 22 8 ) solution was carried out in self-designed bubbling reactor. The experimental results showed that NO removal efficiency was up to 92.9% at pH 11. The results of the thermodynamics calculation verified that NO removal by using strong alkaline dual oxidant (H 2 O 2 /S 2 O 22 8 ) solution was feasible. The results of the kinetic study showed that the reaction between NO and dual oxidant (H 2 O 2 /S 2 O 22 8 ) in strong alkaline condition was found to be 1.5-order with respect to NO, and the average activation energy of this reaction was 26.32 kJ mol 21 in the quickreaction zone. The ion chromatography (IC) analysis results in strong alkaline condition showed that NO 2 3 and SO 22 4 were the final ionic product in spent reaction solution. This dual oxidant (H 2 O 2 /S 2 O 22 8 ) was a promising oxidant for the simultaneous wet removal of NO and SO 2 with high efficiency, no secondary pollution and low cost.

A wet process for oxidation-absorption of nitric oxide by persulfate/calcium peroxide

“…1-2), which is an oxidant with a similar function to • OH. Adewuyi et al [5,12] studied the In our previous studies [22,23] , we also showed that the combination of S 2 O 8 2and H 2 O 2 had a significant synergistic effect on NO removal. In addition, the NO removal efficiency under alkaline conditions was much higher than that under acidic or neutral conditions, reaching 80 % or higher for a long period of time under strongly alkaline conditions adjusted by the addition of sodium hydroxide (NaOH).…”

“…While the free radicals might be captured by O 2 [33] , the oxidation and absorption of NO was also promoted by O 2 (See Eqs. [22][23]. The effect of O 2 concentration on NO removal efficiency was less obvious.…”

Thermodynamic and kinetic performance of an S2O82‐/CaO2 solution for NO removal

“…It can be seen from Figure that the apparent activation energy of the NO removal by wet scrubbing using the oxidative absorbent S 2 O 8 2‐ /CaO 2 is 53.0 kJ/mol based on Equation . In previous research, the apparent activation energies of the NO removal using a NaClO 2 solution, an H 2 O 2 /Na 2 S 2 O 8 strong alkali solution, and an H 2 O 2 /NaOH solution were 42.5, 26.3, and 27.8 kJ/mol, respectively . These results show that the apparent activation energy of the NO removal by wet scrubbing using the oxidative absorbent S 2 O 8 2‐ /CaO 2 is higher than that of other oxidants and absorbents.…”

“…In previous research, the apparent activation energies of the NO removal using a NaClO 2 solution, an H 2 O 2 /Na 2 S 2 O 8 strong alkali solution, and an H 2 O 2 /NaOH solution were 42.5, 26.3, and 27.8 kJ/mol, respectively. [21][22][23] These results show that the apparent activation energy of the NO removal by wet scrubbing using the oxidative absorbent S 2 O 8 2-/CaO 2 is higher than that of other oxidants and absorbents. It is likely that the NO removal reactions of the gas-liquid-solid phases coexisted in the oxidative absorbent (S 2 O 8 2-/CaO 2 ) system.…”