| 초록 |
Mercury (Hg), which is emitted from fossil fuel consumption, has become one of the hazardous issues. The elemental form of Hg (Hg0) is very difficult to remove because of its insolubility and volatility, therefore, it is needed to oxidize Hg0 into Hg2+ which is soluble and easily removed. Among various types of mercury removal catalysts, VOx/TiO2, which control NOx emissions in SCR (Selective Catalytic Reduction) unit, can oxidize Hg0. However, in mercury oxidation, there is no case where the activity is increased by changing the catalyst support. Herein, using density functional theory (DFT) calculations, pure and reduced TiO2 with anatase and rutile phase were used to investigate the effects of crystal phase and reduction treatment on the catalytic activity. We revealed that the oxygen vacancy on the reduced TiO2 led to structural transformation of V2O5, thus changing the oxidation state of V from 5+ to 4+. Consequently, thermodynamic, kinetic and electronic analyses showed that manipulating support structure can change vanadium state of active site which resulted in enhancement of mercury oxidation activity. |
