Adsorption of Hydrogen Chloride on Soot and Fly Ash

Abstract

Adsorption of hydrogen chloride vapor over coal combustion soot, coal combustion fly ash, oil combustion fly ash and carbon black was measured. The amount of HCl adsorbed was largely dependent on the property of the adsorbent. The amount of HCl over soot and fly ash changed with relative humidity, but slightly with HCl concentration. The fly ash held the largest amount of HCl, which developed into more than seven layers of HCl at relative humidity of 80%(25°C). The ratio of HCl and H₂O over coal combustion fly ash was independent of relative humidity.
The effect of surface upon HCl adsorption was discussed on the assumption that adsorbed HCl was in the form of H₃O⁺Cl^-. The implication of the HCl adsorption upon health effect was also discussed.