Fredrik Jareman

Preparation and evaluation of thin ZSM-5 membranes synthesized in the absence of organic template molecules

Porous α-alumina supports with a pore size of 100 nm were seeded with colloidal TPA-silicalite-1 crystals with a size of 120 nm. The seeded supports were calcined and treated in a synthesis solutio ...

Effects of aluminum content on the separation properties of MFI membranes

MFI membranes with almost identical film thickness and defect distribution but different Si/Al ratio were evaluated by separation of butane and hexane isomers. Film thickness was evaluated by SEM and defect distribution by porosimetry. When the temperature was varied, the membranes showed similar separation trends for butanes, but clear differences were observed for hexane separation. The hexane separation factor varied with temperature for the silicalite-1 membrane but was constant for the ZSM-5 membrane. It is believed that this difference may be a result of differences in adsorption properties.

Application of the seed-film method for the preparation of structured molecular sieve catalysts

Abstract The seed-film method has been applied for the preparation of various materials of potential interest as structured molecular sieve catalysts. The method has proven to be very flexible and allows for the reproducible preparation of a number of molecular sieve–substrate combinations as well as the control of the materials’ properties of importance in catalytic applications such as zeolite loading, film thickness, film density and crystal orientation. The preparation of thin molecular sieve films on ceramic foams, α-alumina pellets and porous alumina supports as well as various metal surfaces is described. The preparation of zoned coatings with a compositional gradient is also discussed.

Accurate measurement of the thermal expansion of MFI zeolite membranes by in situ HTXRPD

Template removal by calcination of MFI type membranes is often accompanied by crack formation. The thermal behavior of MFI type membranes, synthesized with and without masking, was studied to under ...

Factors affecting the performance of MFI membranes

Abstract Thin MFI membranes with varying morphology have been prepared using high flux alumina supports using an advanced synthesis procedure employing support masking and seeding. Evaluation of membrane quality by physical characterization and permeation measurements revealed a number of factors affecting the membrane performance. In the present work, the effects of film thickness, support type, preferred orientation and calcination rate are discussed. Some quality criteria for zeolite membranes are also debated and the porosimetry technique is discussed.

Silicalite-1 membranes with small crystal size

Abstract Silicalite-1 membranes with small crystal size were prepared using a multiseeding method, were the support was repeatedly seeded and exposed to a short hydrothermal treatment up to five times. The films were characterized using SEM, single gas permeation, porosimetry and mixture separation experiments. Films with three or four layers were of high quality i.e with minor defects according to the porosimetry experiments but showed poor separation of binary mixtures. This result may be attributed to the small crystal size and/or large amount of grain boundaries in the films.