Enhancing denitration with sulfite solution by confinement effect of tetrahexylammonium bromide: Mechanism and kinetics

Abstract

This study proposes a novel method of using the surfactant tetrahexylammonium bromide (THABr) to enhance the denitration performance of sulfite solution. Experiments and quantum‐chemical calculations demonstrate that THABr captures free radicals, aggregates into micelles that promote radical self‐annihilation, suppress the undesired oxidation of SO ₃ ²⁻ , and markedly enhances NO ₂ absorption. Consequently, denitration efficiency rose from 82.72% to 95.51%, effective absorption duration extended from 0 to 79 min, and absorption capacity increased from 0.026 to 0.104 NO ₂ /Na ₂ SO ₃ . THABr remains non‐consumptive during the process, and cyclic stability tests have demonstrated its potential for long‐term application. Influences of key operating parameters were evaluated and a macroscopic kinetic model is provided for industrial scale‐up.