Development of nitric oxide removal and regeneration system using Fe(II)(DMPS)2

Abstract

Fe(II)(DMPS)2 was used as an absorbent for removing nitric oxide(NO) in impeller-based wet scrubber. NO must be removed because it is not only a precursor of secondary particulate matter, but also has a harmful effect on the environment and human body. To this end, selective catalytic reduction (SCR) has been applied in most industries where nitric oxide emitted for removing nitric oxide because of its high efficiency and easy operation. On the other hand, SCR has fatal issues such as the driving cost is too high and ammonia slip phenomenon that ammonia escapes without responding. For this reason, the development of new technology to overcome the limitations of SCR. To this end, Fe(II) chelate absorbent based wet scrubber was studied. The most well-known absorbent for NO treatment is Fe(II)EDTA due to the its high NO removal efficiency and economical price, however, Fe(II)EDTA easily oxidized to Fe(III)EDTA which lead to lose its NO absorption capacity. To overcome the efficiency dropped, Fe(II)(DMPS)2 which has superior anti-oxidation capacity was used high NO removal and durability of the process. Also, the response surface methodology (RSM) was applied to determine the optimizing condition for NO absorption, which affected by pH, molar ratio of Fe(II) to DMPS and liquid to gas ratio. In addition, the physical regeneration method and the electrochemical regeneration method were performed and compared to regenerate absorbent for continuous operation.