Microwave assisted hydrolysis of aluminium metal and preparation of high surface area γ Al2O3 powder

Abstract

Phase pure boehmite particles were prepared by microwave assisted hydrolysis of aluminium sheets. These particles were calcined in air to produce g Al 2 O 3 particles with specific surface area of~210 m 2 /g. The alumina particles were characterized by studying X-ray diffraction, transmission electron microscopy and Fourier transform infrared spectroscopy. For comparison, the aluminium hydroxide particles were also prepared by normal hydrolysis of aluminium metal. Normal hydrolysis yielded a mixture of boehmite and bayerite particles whereas microwave assisted hydrolysis produced phase pure boehmite particles. The importance of using microwave radiation for the hydrolysis of aluminium metal is also manifested in a shorter reaction time.

A Novel Synthesis Route of Mesoporous γ-Alumina from Polyoxohydroxide Aluminum

“…Thus, the search for synthetic routes for obtaining new selected materials with the desired properties is aimed [1][2][3][4][5] . Alumina compounds are known to present exceptional structural stabilities and quite large specific surface areas, one of the reasons why these compounds are widely used for catalysis and adsorption processes [6][7][8][9][10][11][12] . The narrow connection that exists between the structure of the starting material and that of the target can be exemplified in the preparation of several types of aluminas such as corundum (α -Al 2 O 3 ) and several transition aluminas (x-, K-, γ-, δ-, e-, η-Al 2 O 3 ) commonly synthesized at different temperatures by calcination of their trihydroxide and oxyhydroxide precursors [13][14][15][16][17][18][19][20] .…”

Microwave-hydrothermal synthesis of mesoporous $$\upgamma $$ γ - $$\hbox {Al}_{2}\hbox {O}_{3}$$ Al 2

“…The synthesis of mesoporous γ -Al 2 O 3 has been reported using different methods, like sol-gel [1], evaporation-induced self-assembly (EISA) [2,3], hardtemplate route [4], flame pyrolysis [5], control precipitation [6], hydrothermal [7], combustion synthesis [8] etc. Recently, microwave heating is a widely used technique for material synthesis due to its several advantages like rapid volumetric heating, dramatic increase in reaction rates, direct interaction of microwave energy with the reaction system, short reaction time and reduced energy consumption as opposed to the conventional heating process [9,10]. Synthesis of mesoporous alumina by the microwave-assisted hydrothermal method has rarely been reported.…”