ABSORPTION OF NO AND SO₂ IN FE(II)-EDTA SOLUTIONS I. ABSORPTION IN A DOUBLE STIRRED VESSEL

Abstract

A double stirred vessel with a plane gas-liquid interface was used to measure the absorption rates of (i) NO in aqueous solutions of Fe(II)-EDTA, (ii) NO and SO₂ in mixtures of Fe(II)-EDTA and Na₂SO₃ or Na₂SO₃, at 25°C and 1 atm. The forward rate constants, k₂, of the complexing reaction NO + Fe(II)-EDTA→Fe(II)(EDTA)(NO) at various liquid temperatures between 25-80°C and liquid concentrations between 0.01-0.05 mol/dm³ were deduced from chemical absorption theory. The results showed that k₂ increases only slightly within 25-80°C and 0.01-0.05 mol/dm³. The rate of absorption of NO during the simultaneous absorption of NO and SO₂ was higher than the rate of single NO absorption when Na₂SO₃ was added to the Fe(II)-EDTA. Na₂SO₃ can replace Na₂SO₃, when SO₂ is absorbed together with NO.

KEYWORDS:

• Absorption
• NO and SO₂
• Fe(II)-EDTA
• Stirred vessel