Patents
The invention describes an improved process for the preparation of ultra-light hydrated alumina from aluminium salts/ Bayer's liquor. The main features of this invention are (a) to obtain hydrated alumina having tap density in the range of 0.098 to 0.32 g/cc, (b) to achieve the precipitation efficiency of less than 99%, (c) to instantaneously precipitate hydrated alumina by hydrothermally treating the Al3+ solution containing urea (Urea/ Al3+ mole ratio between 2:1 to 4:1) in the temperature range of 160 to 180?C. The precipitate thus obtained is filtered, washed and dried to obtain the desired product.