A NOVEL FIBEROPTIC BASED TECHNIQUE FOR THE SPECTROPHOTOMETRIC MEASUREMENT OF PHASE AND CHEMICAL-EQUILIBRIUM OF (SULFUR-DIOXIDE PLUS WATER) AT ELEVATED-TEMPERATURES

The spectrophotometric technique described in a previous communication has been developed further to study the phase and chemical equilibriu m for (sulphur dioxide + water) at elevated temperatures pertinent to flue gas purification. Both the vapour and the liquid phase have been analysed in situ. The analysis of the vapour phase has been performed with the help of a diode array u.v. spectrophotometer equipped with si lica fibre light guides. The liquid phase has been analysed using a fi bre-optic coupled immersion probe. Experimental results for the equili brium partial pressures of (sulphur dioxide + water) at very low SO2 c oncentrations, typical for flue gases, are reported at T = (298.20, 31 2.95, 322.70, and 332.50) K. The chemical equilibrium in the liquid ph ase is also presented in terms of dissociated and undissociated sulphu r dioxide in aqueous solution. (C) 1997 Academic Press Limited.