Lithium aluminosilicate gels and powders with Li_2O and Al_2O_3 contents ranging from 9.3 to 20 and 10.0 to 28 mol%, respectively, were prepared in different experimental conditions. Tetraethyiortosilicate and aluminium nitrate nonahidrate and lithium nitrate were used as raw materials. Hydrocloric acid and ammonia were used as catalysts. Gels were prepared with two molar ratios water/alkoxides. Powder samples were prepared by precipitation on diluted ammonia or by pyrolysis. The crystallization of β-spodumene and β-eucryptite was observed to be dependent on sample composition and on the preparation conditions, in gel or powder forms. Mullite formation was detected on those samples prepared by precipitation. Lithium disihcate appeared only for the sample prepared by pyrolysis (sample SCK) together with β-spodumene crystallization. For the precipitated powders (dried at 120°C, 48 hours) a specific surface area of 600m~2·g~(-1) was observed which reduces to 270 m~2.g~(-1) after heat treatment at 1200°C (2 hours). Sample SCK presents a specific surface area of 23m~2·g~(-1) and 0.49m~2·g~(-1) before and after heat treatment, respectively.
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