Abstract: The invention relates to a method for producing alkali metal cyanides as solids, comprising the steps: i) an absorption step in the form of the absorption of hydrogen cyanide from a syngas containing hydrogen cyanide in an aqueous alkali metal hydroxide solution; ii) a preparation step for the waste gases containing cyanide that have accumulated in step i); iii) a crystallization step in the form of the introduction of the alkali metal cyanide solution into an evaporative crystallizer; iv) a condensation step for the vapour containing cyanide that has accumulated in step iii) to obtain a vapour condensate containing cyanide; v) a recirculation step, in which the vapour condensate containing cyanide that has been obtained in step iv) is used as an aqueous liquid in step ii).

Abstract: The invention relates to a process for the preparation of alkali metal cyanides as a solid substance, comprising the steps of: i) an absorption step in the form of an absorption of hydrogen cyanide from a hydrogen cyanide-containing synthesis gas in an aqueous alkali metal hydroxide solution; ii) a crystallization step in the form of introducing said alkali metal cyanide solution into an evaporative crystallizer; iii) a separation step; iv) a recycle step; v) a drying step.

Abstract: The invention relates to a method for producing shaped inorganic cyanide bodies, especially made of alkaline metal cyanides and alkaline earth metal cyanides, by pressing particulate inorganic cyanide obtained by means of a crystallization method. According to the invention, a cyanide crystallate separated from a mother liquor by means of a solid-liquid separation device and containing 2-15 wt. % water is fed to a forming device without the addition of an auxiliary forming agent and placed under pressure and compressed to form shaped bodies containing 0.1-12 wt. % water. The amount of water contained by the shaped bodies is always less than that contained in the crystallates used for the production thereof. Preferably, the crystallite is pressed out of a rotary filter or a centrifuge at a temperature of more than 40° C. to form shaped bodies containing 0.2-6 wt. % residual water. The inventive method can be carried out in a more economical manner than previously known methods using dried cyanide.

Abstract: The invention relates to a method for producing shaped inorganic cyanide bodies, especially made of alkaline metal cyanides and alkaline earth metal cyanides, by pressing particulate inorganic cyanide obtained by means of a crystallization method. According to the invention, a cyanide crystallate separated from a mother liquor by means of a solid-liquid separation device and containing 2-15 wt. % water is fed to a forming device without the addition of an auxiliary forming agent and placed under pressure and compressed to form shaped bodies containing 0.1-12 wt. % water. The amount of water contained by the shaped bodies is always less than that contained in the crystallates used for the production thereof. Preferably, the crystallite is pressed out of a rotary filter or a centrifuge at a temperature of more than 40° C. to form shaped bodies containing 0.2-6 wt. % residual water. The inventive method can be carried out in a more economical manner than previously known methods using dried cyanide.

Abstract: The invention relates to a method for producing shaped inorganic cyanide bodies, especially made of alkaline metal cyanides and alkaline earth metal cyanides, by pressing particulate inorganic cyanide obtained by means of a crystallization method. According to the invention, a cyanide crystallate separated from a mother liquor by means of a solid-liquid separation device and containing 2-15 wt. % water is fed to a forming device without the addition of an auxiliary forming agent and placed under pressure and compressed to form shaped bodies containing 0.1-12 wt. % water. The amount of water contained by the shaped bodies is always less than that contained in the crystallates used for the production thereof. Preferably, the crystallite is pressed out of a rotary filter or a centrifuge at a temperature of more than 40° C. to form shaped bodies containing 0.2-6 wt. % residual water. The inventive method can be carried out in a more economical manner than previously known methods using dried cyanide.