Mechanism of zeolite crystallization and thermochemical properties of some synthetic zeolites. Final report
During the period of 4/1/82 to 9/30/84, the Department of Energy has provided support for laboratory synthesis of zeolites, calorimetric determinations, and thermal analyses on synthetic zeolites. This Final Report to the DOE is written as 6 independent sections. The study is more readily divisible into two parts: the first half deals primarily with synthesis experiments in which zeolites having phillipsite, merlinoite and gismondine structure are precipitated from clear solutions at 80/sup 0/C in the system K/sub 2/O-Na/sub 2/O-Al/sub 2/O/sub 3/-SiO/sub 2/-H/sub 2/O, and the second half presents a calorimetric study of synthetic merlinoite samples having various Si/Al and Na/(Na + K) ratios. Section 1 describes the zeolite synthesis method, the characterization of the solutions and synthetic zeolites, and investigates the zeolite stability fields. Section 2 describes the results of three sets of precipitation experiments in which the effect of solution composition and structure on the composition, structure, crystallization pathway and growth kinetics of the synthesized zeolites was studied. Low-temperature heat capacities measured by adiabatic calorimetry and derived thermodynamic functions for the synthetic merlinoites are presented in Section 3. Section 4 gives the heats of solution determined by hydrofluoric acid solution calorimetry and enthalpies of formation for these samples. The calculated Gibbs free energies of formation and application of the data to mineral equilibria typical of saline, alkaline lakes are the subjects of Section 5. The final section describes stability relations of 3 common Ca-zeolites laumontite, heulandite and stilbite, and application of their natural parageneses in geothermal areas and low-grade metamorphic terranes.
- Research Organization:
- Stanford Univ., CA (USA). Dept. of Geology
- DOE Contract Number:
- AT03-82ER12051
- OSTI ID:
- 6494128
- Report Number(s):
- DOE/ER/12051-T1; ON: DE85001293
- Resource Relation:
- Other Information: Portions are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
Similar Records
Review of stabilities of analcime and some calcium zeolites. [Stilbite, lawsonite, prebnite, laumontite, and wairakite]
Montesommaite, (K,Na) sub 9 Al sub 9 Si sub 23 O sub 64 ter dot 10H sub 2 O, a new zeolite related to merlinoite and the gismondine group