| 摘要 |
962,590. Aluminium ammonium alum and aluminium sulphate. INSTYTUT CHEMII OGOLNEJ. Dec. 7, 1961 [July 14, 1961], No. 43913/61. Heading C1A. Pure aluminium ammonium alum and technical aluminium sulphate are obtained from aluminium containing raw material by decomposing the raw material with a solution of sulphuric acid containing a quantity of the lye obtained from a previous aluminium ammonium alum crystallization process, there being present an excess of sulphuric acid over that theoretically required, filtering off the solids, and adding ammonium sulphate to precipitate aluminium ammonium alum crystals. The lye obtained after this crystallization is divided into two parts, one of which is recycled to the start of the process as above, and the remainder is concentrated by evaporation and after removal of solids is added to aluminium raw materials to produce technical aluminium sulphate. The raw materials used include clay, kaolin, shale and bauxite. |
