| 摘要 |
Aluminium polychlorosulphates of formula Al(OH)aClbYc/dM'Cl2/eM"Cl (I), in which Y = an anion with a valency of 2, such as SO4<2->, M' = a cation with a valency of 2, such as an alkaline earth, M" = a cation with a valency of 1, such as an alkali metal or ammonium, a, b, c and d are whole numbers or fractions and are not zero and e = 0, a whole number or a fraction such that 1.8 <a< 2.25, 0.001 <c< 0.150, b = 3-2c-a and 2d+e+b ≤ 3, and having a basicity beta of 60-75 % where beta = 100 x (3Al + 2M' + M" - 2Y - Cl)/3Al in which Al, M', M", Y and Cl are expressed in moles, are prepared by contacting a basic compound of an alkali metal, preferably in aqueous solution, and at least one basic compound of an alkaline earth metal or a halide of an alkaline earth metal, in aqueous suspension or as a powder, in the presence of sulphate ions, with a solution of basic aluminium chloride of formula Al(OH)xCly in which x = 0.1-1.5 and y = 3-x, at a temperature of from ambient temperature e (ca. 25 degrees C) to 70 degrees C, then after basification has been accomplished the reaction mixture is heated at a temperature of 60-95 degrees C for a period which is dependent on the cooking temperature, i.e. for 3-20 (5- 9) hours at 60 degrees C or for 5-15 (7-10) minutes at 95 degrees C. |
