Microwave drying of boehmite sol intercalated smectites

✍ Scribed by K. G. K. Warrier; P. Mukundan; S. K. Ghosh; S. Sivakumar; A. D. Damodaran

• Book ID: 104735644
• Publisher: Springer
• Year: 1994
• Tongue: English
• Weight: 600 KB
• Volume: 29
• Category: Article
• ISSN: 0022-2461
• DOI: 10.1007/bf00352042

✦ Synopsis

Monohydroxy aluminium oxide (boehmite) intercalated (cross-linked) smectites (SCLS) have been prepared from an aqueous suspension containing sodium mono-ion-exchanged bentonite (2 wt%) and boehmite (AIOOH) sol at pH 3.5 and at 32~ The SCLS has been separated by centrifugation and repeated washing. The intercalated smectite was dried in an oven at 60~ over a period of 24 h and also in a microwave oven of 2.45 GHz frequency and 600 W power over a range of 3-15 min. Both samples have identical thermal and electrical properties. However, the microwave-dried samples have a distinctly higher surface area of 120 m 2 g-~., stable up to 650~ with a marginal reduction to 116 m 2 g-~ compared with 94 m 2 g-1 for the oven-dried sample. Similarly there was clear difference in the morphological features of the two samples, the air-dried sample having a close packed structure while the microwave one is delaminated and porous.