Removal of NO from Flue Gas by a Heterogeneous Fenton-Like Process

An iron-containing polyoxometalates (POMs) complex (Fe(III)AspPW) was synthesized from ferric chloride, aspartic acid, and phosphotungstic acid for developing a novel method based on a Fenton-like process using Fe-containing POMs as heterogeneous catalyst to remove NO from flue gas. The effects of various experimental parameters on NO removal efficiency were evaluated in a self-made bubbling reactor. Under optimized conditions, an average removal efficiency of >90% was obtained. The dominant reactive species generated in the system was suggested to be (OH)-O-center dot by adding the (OH)-O-center dot quenching agent of tert-butanol and the main reaction product was identified as nitrate. A possible catalytic mechanism was proposed on the basis of experimental results and references. The catalysis might result from the redox cycles of (FeFeII)-Fe-III and POMPOM- on the surface of Fe(III)AspPW, and the high catalytic activity of Fe(III)AspPW might be attributed to the chemisorption of H2O2 on its surface by hydrogen bonding.