KINETICS OF THE REACTION BETWEEN SOLID ACTIVE SODIUM-CARBONATE OF THE2ND GENERATION AND THE GASEOUS SULFUR-DIOXIDE

The results are presented of a detailed experimental kinetic study of the heterogeneous reaction between gaseous sulfur dioxide and the soli d active sodium carbonate of the second generation which has been prep ared by a controlled thermal dehydration of higher hydrates of the sod ium carbonate. The measurements have been carried out in an all-glass kinetic apparatus with an integral fixed-bed reactor. The reaction cou rse was studied in dependence on genesis and nature of the active sodi um carbonate, on temperature and on composition of the gas phase. The reaction rate is significantly affected by presence of the water vapou r which acts as a gaseous catalyst. Experimental data have been treate d by using the model proposed by Erdos (Collect. Czech. Chem. Commun. 32, 1653 (1967), and the values of the effective reaction rate constan ts have been computed. The kinetic study of active sodium carbonate of the second generation has been completed by the determination of micr ostructure (SEM) of solid samples before and after reaction, and by de termining the solid surface composition before and after reaction by m eans of electronic spectra (ESCA).