The Malaysian Journal of Analytical Sciences Vol 11 No 1 (2007): 262 -268

.

 

SYNTHESIS OF ALUMINA USING THE SOLVOTHERMAL METHOD

 

Meor Yusoff M.S. and Masliana Muslimin

 

Materials Technology Group,Industrial Technology Division,

Malaysian Institute for Nuclear Technology Research, Bangi,

43000 Kajang, Selangor,

 

Abstract

The paper describes work done on synthesis of α- and ?- alumina by using the solvothermal technique. Synthesis of both these aluminas involves the transition reactions of the aluminium hydroxide into alumina by a dehydroxylation process. As there are many forms of transition aluminas produced during this process, x-ray diffraction (XRD) technique was used to identify α-alumina and ?- alumina.  After establishing the optimum conditions for the production of a single-phase α- and ?- aluminas, characteristic study on the product was performed. An important parameter in establishing nanosized powders is their crystallite size and analysis of the ?-alumina shows that it is a nanosized powder with a size of 28 nm while the α-alumina has a crystallite size of 200 nm. Other properties analysed include morphology, surface area and particle size.

 

Keywords: α-alumina, ?- alumina, solvothermal, crystallite size, XRD

 

References

1.         Cambridge  E.L.,  Raouf  O.  L.,  Withers  J.C.  and  Blake  D.  M.,  1987,  Production  of  high  purity  alumina,  U.S.  Patent  No. 4,634,581.

2.         Gitzen W. H., 1963, Production of low-soda alumina, U.S. Patent No. 3,092,452.

3.         Joaquin Aquilar- Santillan, Heberto Balmori-Ramirez and Richard C. Bradt, 2004, Sol- gel formation and kinetic analysis of the in-situ/self-seeding transformation of bayerite t o a -alumina, Journal of Ceramic Processing Research, 5(3), 196 -202

4.         Temuujin J., Jadambaa Ts., Mackenzie K.J.D., Angerer P., Porte F. and Riley F., 2000, Thermal formation of corundum from aluminium hydroxides prepared from various aluminium salts, Bull. Mater. Sci., 23 (4), 301-304.

5.         Kano J., Saeki S., Saito F., Tanjo M., Yamazaki  S., 2000, Application  of dry grinding to reduction  in  the transformation temperature of alumina hydroxides. Int. J. Miner. Process. 60, 91-100.

6.         Schicker S., Garcia D. E., 1999, Wet  milling of Fe/Al/Al2O3      and Fe2O3/Al/Al2O3     powder mixtures, Journal of the American Ceramic Society, 82 (10), 2607-2612.

7.         Bahlawane  N.  and  Watanabe  T.,  2000,  New  sol-gel  route  for  the  preparation  of  pure  a-alumina  at  950 0C.  Journal  of  the American Ceramic Society, 83 [9].