Heterogeneous reactions of gaseous methanesulfonic acid with calcium carbonate and kaolinite particles

Heterogeneous reactions of gaseous methanesulfonic acid (MSA) with calcium carbonate (CaCO3) and kaolinite particles at room temperature were investigated using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC). Methanesulfonate (MS-) was identified as the product in the condensed phase, in accordance with the product of the reaction of gaseous MSA with NaCl and sea salt particles. When the concentration of gaseous MSA was 1.34 x 10(13) molecules cm(-3), the uptake coefficient was (1.21 +/- 0.06) x 10(-8) (1 sigma) for the reaction of gaseous MSA with CaCO3 and (4.10 +/- 0.65) x 10(-10) (1 sigma) for the reaction with kaolinite. Both uptake coefficients were significantly smaller than those of the reactions of gaseous MSA with NaCl and sea salt particles.