Abstract
Performance of simultaneous desulfurization and dinitration using the solution of NaClO2 and NaClO as new-style complex absorbent was investigated experimentally in self-designed bench scale bubbling reactor. The effects of main parameters, such as the concentrations of NaClO2 and of NaClO, solution pH and reaction temperature and so on, on removal efficiencies of SO2 and NOx, were examined, then the optimal conditions were established, in which the molar ratio of NaClO to NaClO2 was 1:1, the reaction temperature was 50°C and the solution pH was 5.5. The removal efficiencies of SO2 and NO under the optimal conditions were 100% and 89.2%, respectively. The mechanism of simultaneous removal based on complex absorbent was proposed by analyzing the removal products and the electrode potentials of related species, namely SO2 and NO are oxidized by chlorite anion, hypochlorite, chlorine dioxide and chlorine contained in complex absorbent. In thermodynamic aspect, simultaneous desulfurization and denitration reactions in liquid phase can happen spontaneously and completely, and are all exothermic reactions. It was confirmed by kinetics that for simultaneous desulfurization and dinitration, the reaction order and average activation energy of SO2 were 1 and 21.6 kJ·mol−1, respectively, and those of NO were 1 and 8.2 kJ·mol−1, respectively.
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Zhao, Y., Guo, T., Liu, F. et al. Performance of simultaneous desulfurization and denitration in liquid phase with new-style complex absorbent. Sci. China Technol. Sci. 54, 3009–3016 (2011). https://doi.org/10.1007/s11431-011-4529-3
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DOI: https://doi.org/10.1007/s11431-011-4529-3