| 摘要 |
The invention relates to new alkali cyanide granules based on sodium cyanide or potassium cyanide and also a process for the preparation thereof. Commercial alkali cyanide granules comprise irregular particles: disadvantages are, in particular, the tendency to form dust and lumps. Alkali cyanide granules of the invention have practically no abrasion and a reduced tendency to form lumps. The granules are characterised by essentially spherical particles, particle diameters in the range from 0.1 to 20 mm, a bulk density above 600 g/dm<3>, an abrasion of less than 1% and a caking index of at most 4. The granules can be prepared by fluidised-bed spray granulation, by an aqueous solution containing an alkali cyanide being sprayed on alkali cyanide nuclei in a fluidised bed and water being evaporated. |
