Reactor for producing a nitrile compound and method for operating the reactor

Abstract

A reactor for producing a nitrile compound from a carbon ring or heterocyclic compound having organic substituents by a gas phase reaction using a fluidized catalyst bed with ammonia and a gas containing oxygen. In a cylindrical fluidized catalyst bed having a diameter of 2.0 meters or greater, partial vaporization-type cooling tubes (the cooling medium is partially vaporized in the tubes) and complete vaporization-type cooling tubes (the cooling medium is completely vaporized in the cooling tubes) are disposed in a specific arrangement. Water containing ionic SiO 2 in 0.1 ppm or smaller and having an electric conductivity of 5 μS/cm or smaller is used as the cooling medium for the complete vaporization-type cooling tubes. The temperature of the reaction is easily stabilized and uniform distribution of temperature is obtained in the fluidized catalyst bed. Stable continuous operation is achieved for a long time in a commercial scale apparatus.

What is claimed is:  
     
         1 . A reactor for producing a nitrile compound from a carbon ring compound having organic substituents or a heterocyclic compound having organic substituents by a gas phase reaction using a fluidized catalyst bed with ammonia and a gas containing oxygen, the reactor comprising cooling tubes which are disposed in a cylindrical fluidized catalyst bed having a diameter of 2.0 meters or greater and comprise cooling tubes of a partial vaporization type in which a portion of a cooling medium is vaporized in the tubes and cooling tubes of a complete vaporization type in which an entire cooling medium is vaporized in the cooling tubes.  
     
     
         2 . A reactor according to  claim 1 , wherein the cooling tube is a cooling tube having a vertical U-shape.  
     
     
         3 . A reactor according to  claim 2 , wherein an equivalent diameter defined by equation (1) in an arbitrary horizontal section of a region in the fluidized catalyst bed where the cooling tubes exist is in a range of 0.2 to 2.0 m and at least a portion of the cooling tubes exists in an arbitrary circle having a same diameter as the equivalent diameter and placed in the section, equation (1) being:  
         DE= 4 ×AF/LW   (1) 
       wherein 
 DE (m): the equivalent diameter  
 AF (m 2 ): an area of a horizontal section of a flow route of the fluidized catalyst bed  
 LW (m): a length of circumferences where the horizontal section of the flow route contacts the fluidized catalyst bed (a circumferential length of dipping)  
 
     
     
         4 . A reactor according to  claim 3 , wherein a ratio (S2/S1) of a surface area (S2) to a surface area (S1) of the cooling tubes is in a range of 0.01 to 0.30, wherein 
 S1 represents an entire surface area of the cooling tubes existing in a vertical cylinder having, in an region in the fluidized catalyst bed where the cooling tubes exist, a bottom face as an arbitrary horizontal section of the region and an arbitrary height; and    S2 represents a surface area of cooling tubes in use existing in a arbitrary vertical cylinder having a bottom face as a circular section which is present in a same plane as that of the bottom face of the cylinder described for S1 and has a same diameter as the equivalent diameter and a same height as that of the cylinder described for S1.    
     
     
         5 . A method for operating a reactor for producing a nitrile compound which comprises using water having a concentration of ionic SiO 2  of 0.1 ppm or smaller and an electric conductivity of 5 μS/cm or smaller as a cooling medium supplied to a cooling tube of a complete vaporization type in the reactor for producing a nitrile compound described in  claim 1.