Effect of drying method on the specific surface area of hydrated lime: A statistical approach

Dry hydrated lime is an air binder often used in architectural injection grouts. This study compared the influences of three commercially available dry hydrated limes on the injection grouts’ workability and mechanical properties. The main differences between the limes were in their chemical and mineralogical composition and Blaine specific surface area. The grouts were composed of dry hydrated lime, finely ground limestone filler, water, and super plasticiser. Subsequent results obtained revealed that the Blaine specific surface area is not directly related to the fresh grout properties. Grain size distribution and shape of lime particles and their aggregates in the water suspension are key parameters influencing the following fresh grout properties: fluidity, injectability, the mixture’s stability, and water retention capacity. However, the lime injection grouts’ mechanical strengths were higher in relation to an increase in the content of portlandite and the Blaine specific surface area of the dry hydrate.

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Preparation of barium hexa-aluminate aerogel

Journal of Materials Research ◽

10.1557/jmr.1994.2272 ◽

1994 ◽

Vol 9 (9) ◽

pp. 2272-2276 ◽

Cited By ~ 8

Author(s):

Yasuyuki Mizushima ◽

Makoto Hori

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Powder Processing ◽

Chelating Agent ◽

Supercritical Drying ◽

High Specific Surface Area ◽

Drying Method

Barium hexa-aluminate (BaO · 6Al2O3) aerogels were prepared using a supercritical drying method and their properties examined. A barium hexa-aluminate aerogel prepared from a double alkoxide of barium and aluminum showed a high specific surface area of 421 m2/g. Monolithic barium hexa-aluminate formed. No BaO · Al2O3 or alumina was observed, as is often the case in powder processing. The specific surface area of the monolithic barium hexa-aluminate fired at 1400 °C for 2 h was 12 m2/g, while that of the barium hexa-aluminate xerogel was only 0.8 m2/g. A barium hexa-aluminate aerogel was also prepared using barium by using a chelating agent. This aerogel showed a specific surface area of 454 m2/g as-dried. In the case of the chelating agent, BaO · Al2O3 was also detected along with barium hexa-aluminate after firing.

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Characteristics of Silica Aerogel Composites Synthesized by Ambient Drying Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.544-545.673 ◽

2007 ◽

Vol 544-545 ◽

pp. 673-676 ◽

Cited By ~ 3

Author(s):

Chang Yeoul Kim ◽

Jong Kyu Lee ◽

Byung Ik Kim

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Silica Aerogel ◽

Pore Diameter ◽

High Specific Surface Area ◽

Ambient Atmosphere ◽

Drying Method ◽

Aerogel Composite ◽

Exchange Surface

Aerogel has its advantages of light density of 0.003-0.35 g/cm3 and its high specific surface area, 600-1000m2/g, mean pore diameter ~20nm. However, aerogel has its disadvantages of fragility and high cost. To overcome the mechanical fragility, we synthesized aerogel composite blankets with glass wools by drying at ambient atmosphere. Colloidal silica sol was first prepared by ion exchanging sodium silicate through amberlite column. Then, glass wool was soaked into the pH-controlled silica aerogel and then gelated. Ageing of silica aerogel composite was conducted in purified water and solvent exchange/surface modification was simultaneously processed in hexane and TMCS solution. After drying at 60oC and heat-treatment at 230oC, we evaluated the properties of aerogel composite, its apparent density and specific surface area.

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