A study on the kinetics of the gas–liquid reaction between nitric oxide and [Fe( <scp>II</scp> ) <scp>NTA</scp> ] ⁻

Abstract Iron nitrilotriacetic acid ([Fe(II)NTA] − ) solution is able to absorb NO from flue gases. In this study, the kinetics of the gas–liquid reaction between NO and [Fe(II)NTA] − has been determined using a double stirred cell. The study indicates that the reaction between NO and [Fe(II)NTA] − is turned into gas film controlling as the [Fe(II)NTA] − concentration is over 0.03 mol L −1 . The reaction rate between NO and [Fe(II)NTA] − is in proportion to the inlet nitric oxide concentration. 50°C is considered to be the best temperature for [Fe(II)NTA] − solution absorbing nitric oxide. The reaction rate between NO and [Fe(II)NTA] − decreases as pH drops below 5.5. The negative effect of pH may be reduced as the [Fe(II)NTA] − concentration increases. The reaction rate between NO and [Fe(II)NTA] − varies little in the pH range from 5.5 to 8.0. The kinetic equation for the gas–liquid reaction between NO and [Fe(II)NTA] − under the controlling of both liquid film and gas film has been obtained as follows: The activation energy E a for the gas–liquid reaction between NO and [Fe(II)NTA] − is 13.06 KJ/mol. stands for the rate of chemisorptions, mol/(m 2 · s); for the NO concentration in the interface, mol L −1 ; and for [Fe(II)NTA] − concentration in the liquid, mol L −1 .