COLL 285 |
| S. Mahdi A. Mehrizy, Fatollah.M Moztarzade, and Encyeh S.Mehrizy. Department of Materials, Materials & Energy Research Center, POBox 11175-488, Tehran, Iran |
| Increasing surface area and porosities control are the most important factors in filters, membranes and catalyst materials. These important parameters are controlable in the freeze drying method by modifying solution concentration. Aluminum sulfate solutions with different concentration were used in the freeze drying process to produce highly nanoporous/ ultra high surface area Alfa- Alumina. Frozen solution drops were dried in vacuum in the same condition. Dehydration and thermal behavior of dried granules were analyzed by STA .Granules were heated for 40 min at 1200 degree Celsius to obtain alfa-alumina that identified by XRD. Morphology, porosities and surface area of the prepared powder were characterized by SEM and BET. Electron Microscopy observation indicated that by solution concentration decreasing the nanoporosities and surface area will develop and the agglomerates morphology of this powder will be modified from voluminous and bulky state to flaky, fibrous and non voluminous that is the best situation for ultrafilters, membranes and catalyst materials. |
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Nanoscience and Nanotechnology
6:00 PM-8:00 PM, Monday, March 29, 2004 Disneyland -- North Exhibit Hall, Poster
Division of Colloid and Surface Chemistry |