Microporous and mesoporous materials vol:23 issue:1-2 pages:119-136
date:Delft Univ Technol, Fac Chem Technol & Mat Sci, NL-2628 BL Delft, Netherlands; Katholieke Univ Leuven, Dept Interfasechem, B-3001 Heverlee, Belgium; ENSCM, Lab Mat Catalyt & Catalyse Chim Organ, CNRS, UMR 5618, F-34296 Montpellier, France; Northeastern Univ, Dept Civil Engn, Snell Engn Ctr 342, Boston, MA 02115 USA
The crystallisation of zeolites and other microporous materials in space has attracted some attention in recent years, in the search for larger or more "pure" and perfect crystals. Hydrodynamics and hydrostatics of zeolite synthesis solutions are strongly influenced by gravitational force, and the growth of zeolites in solutions which are effectively free from convection and sedimentation in micro-gravity may produce crystals of different character to those grown on Earth. The exact nature of the changes which occur on synthesising zeolites in micro-gravity depends upon the chemical and physical properties of the solutions as well as the "quality" of micro-gravity. The results from several experiments performed in space are summarised and discussed, and a few suggestions are made concerning possible improvements in experimental design and strategy. (C) 1998 Elsevier Science B.V. All rights reserved.