Thermochemical investigation of natural fibrous zeolites
Thermochemical investigation of natural fibrous zeolites (in EMPG-VI; Experimental mineralogy, petrology and geochemistry, E. A. J. Burke (editor), C. Chopin (editor), W. V. Maresch (editor), L. Ungaretti (editor) and C. Willaime (editor))
European Journal of Mineralogy (April 1997) 9 (2): 327-332
New experimental data are reported for heat capacities, enthalpies of dehydration and formation of the chemcially analysed fibrous zeolites of the natrolite group, including natrolite, tetranatrolite, scolecite, mesolite, and structural types of thomsonite, edingtonite and gonnardite. The small anomalies in heat-capacity behaviour in the T interval 120-210 K which are associated with phase transformations were observed by the DSC method. The alpha -beta metanatrolite transiton at 836 + or - 3 K was studied and the enthalpy was calculated as 14.1 + or - 10 kJ/mol. The enthalpy of the disordering cation reaction natrolite-tetranatrolite was determined from experiment calorimetric data to be 23.2 kJ/mol.