EARTH

[3913-23-11] Regeneration of Complexing Absorbent and Selective Reduction of NO in NOx Scrubber Solution

○Kaisong Xiang¹, Dongli Wang¹, Xiaofeng Xie¹, Cong Zhang¹, Shu Yang¹, Hui Liu^1,2 (1. Central South University, 2. Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution)

司会（Chairman）：Carlito Tabelin （Hokkaido University）

キーワード：Fe(III)EDTA reduction, phase transfer catalysis, Fe(II)EDTA-NO, selective eletro-reduction

Fe(II)EDTA is one of highly effective denitrification (De-NOx) absorbent, however, can be easily oxidized to ineffective Fe(III)EDTA, which need to be reduced into Fe(II)EDTA. On the other, the absorbent combined with NO, as form of Fe(II)EDTA-NO, need to be converted into other harmless products and release Fe(II)EDTA at the same time. Therefore, the effective regeneration of Fe(II)-EDTA and the selective reduction of Fe(II)EDTA-NO are two critical parts for practical De-NOx application. To accelerate the regeneration of Fe(II)EDTA, Se (Selenium) was first used as catalyst to intensify the reduction of Fe(III)EDTA by Na₂SO₃ solution. The regeneration rate of Fe(II)-EDTA was greatly enhanced by 4 folds after adding Se into Fe(III)EDTA/SO₃^2- system. We characterized this process as a reaction-controlled phase transfer catalysis and proposed the possible mechanism. To convert the adsorbed NO into harmless products. We developed a highly selective and stable catalyst CoSe₂ nanoparticle hybridized with carbon nanotubes (CoSe₂@CNTs). The CoSe₂@CNTs hybrid catalysts performed an extraordinary high selectivity for NH₄⁺ formation in NO electroreduction with minimal N₂O production and H₂ evolution. The above mentioned researches provide a potential approach for simultaneous desulfurization and denitrification and utilization of nitrogen resources.