Patent GB-242685-A (GB)
Title: Improved manufacture of hydrocyanic acid
IPC: C01C3/02
Filed: 1924-06-14
Abstract: Activated carbon for use as a catalyst in the production of hydrocyanic acid is given a content of alkaline material by impregnation with substances such as hydrates, carbonates, silicates, borates, phosphates, sulphides, or cyanides of alkalies or alkaline earths, or compounds may be used which are capable of being transformed into alkaline materials either previous to or during the reaction for the production of hydrocyanic acid; such compounds may be sulphates, nitrates, formates, or acetates of alkalies or alkaline earths.  The activated carbon, which may be mixed with inert materials or deposited on supporting material, may be prepared in situ by heating carbonizable materials such as wood or cellulose in presence of the gaseous carbon and nitrogen compounds serving for the production of hydrocyanic acid, and this is preferably effected so that the carbon is alkalized at the same time; for instance an alkali or alkaline earth salt of a fatty acid of high molecular weight may be used.  An example describes the production of alkaline activated carbon by heating a mixture of sawdust and coal impregnated with alkali to about 800 DEG  C. in a current of ammonia and carbon monoxide.  After the carbonization, the temperature may be reduced to 550-600 DEG  C. for the continued production of hydrocyanic acid. Reference has been directed by the Comptroller to Specification 207,830 (as open to inspection under Sect. 91 of the Act).ALSO:Hydrocyanic acid is obtained by the reaction of gaseous carbon and nitrogen compounds such as carbon monoxide and ammonia in presence of a neutral or alkaline activated carbon at about 400-800 DEG  C.  The activated carbon may be made alkaline by impregnation with substances such as hydrates, carbonates, silicates, borates, phosphates, sulphides or cyanides of alkalies or alkaline earths, or compounds may be used which are capable of being transformed into alkaline materials either previous to or during the reaction for the production of hydrocyanic acid.  Such substances may be sulphates, nitrates, formates or acetates of alkalies or alkaline earths.  The activated carbon may be employed alone or together with inert materials, for instance by mixing the substances or depositing the carbon on supporting material.  The carbon may be prepared in situ by heating carbonizable materials such as wood or cellulose in presence of the gaseous carbon and nitrogen compounds serving for the production of hydrocyanic acid, and this is preferably effected so that the carbon is alkalized at the same time; for instance, an alkali or alkaline earth salt of a fatty acid of high molecular weight may be used. An example describes the production of alkaline-activated carbon by heating a mixture of sawdust and coal impregnated with alkali to about 800 DEG  C. in a stream of ammonia and carbon monoxide. After carbonization the temperature is preferably lowered to 550-600 DEG  C. for the continued production of hydrocyanic acid.  Reference has been directed by the Comptroller to Specification 207,830 (as open to inspection under Sect. 91 of the Act).