Title: Process for preparing alkali metal cyanide and alkaline earth metal cyanide granules and high purity alkali metal cyanide granules obtainable thereby
Application Number: 98100078 Application Date: 1998.01.24
Publication Number: 1190080 Publication Date: 1998.08.12
Approval Pub. Date: 2004.11.17 Granted Pub. Date: 2004.11.17
International Classifi-cation: B01J2/04;C01C3/08;C01C3/10
Applicant(s) Name: Degussa AG Address:
Inventor(s) Name: Rudiger Schutte;Hans Christian Alt;Catrin Becker-B
Attorney & Agent: gan ling
Abstract:
    A process for the direct preparation of alkali metal cyanide and alkaline earth metal cyanide granules from an HCN-containing gas and an aqueous solution or suspension of an alkali metal or alkaline earth metal hydroxide. The reaction is performed in a reactor for fluidized bed spray granulation, wherein a solution or suspension of the hydroxide is sprayed onto seed granules of the cyanide being prepared and at the same time a hydrogen cyanide-containing gas is supplied to the reactor and water is evaporated by means of a fluidizing gas. The preferred fluidizing gas is steam. The reaction gases from a BMA or Andrussow process may be quenched with water and the gas mixture used as fluidizing gas. By using a CO2-free HCN-containing gas, alkali metal cyanide granules with advantageous properties, including a combined concentration of alkali metal carbonate and alkali metal formate of less then 0.4 wt. %, are obtainable.
Time: 10