STUDY OF AGGEGATION MECHANISM AND KINETICS OF ZSM-5 AND
SILICATE-1 NANOSLABS INTO ZSM-5/SILICATE-1 HYBIRD PHASES UNDER NEAR-2 WEIGHTLESS
CONDITIONS (NANOSLAB-1 AND NANOSLAB-2), TWO INVESTIGATIONS
Research Area Material Science
Expeditions: 5 and 8
Principal Investigator(s): ● Johan A. Martens, Katholieke Universiteit, Leuven, Leuven,
Belgium
RESEARCH OBJECTIVES
Silicalite-1 and Zeolite Socony Mobil-5 (ZSM-5) are important
materials in industrial applications. Understanding the effects of
convection and sedimentation during bulk-zeolite formation are
necessary for optimization of existing syntheses. The
investigation studies the aggregation mechanism and kinetics of:
ZSM-5 nanoslabs (SiO2 phase, doped with aluminium), Silicalite-
1 nanoslabs (pure SiO2 phase) and ZSM-5 / Silicalite-1 hybrid
mixture phases under weightless conditions.
RESULTS
Microgravity significantly slowed particle aggregation,
confirming the sensitivity of the process to convection and
shear forces. Microgravity also considerably enhanced the
effect on aggregation of reduced temperatures and charge.
Only the formation and presence of Ordered Liquid Phases
(OLPs) before aggregation can account for these observations,
and an on-ground study confirmed OLP occurrence. The strong
effect of convection and shear forces in microgravity indicates the important role OLPs play,
and their discovery is useful for optimizing zeolite synthesis and design of hierarchical,
functional materials. No results were obtained for the Nanoslab investigations due to a failure.
This investigation is complete; however no publications are expected.
Closeup of Nanoslab in the
Microgravity Science Glovebox. ESA
image.