Process for preparing nitriles

摘要

1,138,696. Preparing nitriles. LUMMUS CO. 28 Oct., 1966 [29 Oct., 1965 (2)], No. 48386/66. Heading C2C. Nitriles are prepared from hydrocarbons of the formula R-X where R is C 1-3 alkyl and X is the group -C(R1)=C(R11)(R111), wherein R1, R11 and R111 are hydrogen or alkyl, or is the group -Ar-R n , wherein Ar is an aromatic nucleus and n is 0 or an integer, the maximum value of n being equal to the number of groups by which the nucleus may be substituted, by contacting the hydrocarbon with NH 3 in the gaseous phase at 400-500‹ C. in the presence of an ammoniation or ammoxidation oxide catalyst in solid form, the catalyst being free of arsenic when the hydrocarbon is an alkene, employing a contact time of 0À01 to 30 secs. and a catalyst on-stream time of less than 30 minutes. The catalyst may be an "ammoniation" catalyst, e.g. associations or mixed oxides of molybdenum and/or tungsten, and of vanadium, iron and/or cobalt, or an "ammoxidation" catalyst, e.g. bismuth oxide/molybdena. Other catalysts, e.g. associations of molybdena and bismuth oxide or ferric oxide such as Fe 2 O 3 Mo 6 O 18 , associations of iron and arsenic oxides, associations of stannic oxide and vanadia, H 4 SiMo 12 O 40 , Bi 4 O 6 (H 4 SiMoO 40 ) and Bi 3 O 4 . 5 (H 3 PMo 12 O 40 ) may also be used. The catalyst may be supported on or mixed with an inert support and it may be reactivated by treatment with a free oxygencontaining gas. The process, which may be conducted intermittently or continuously, may be effected at a pressure of 1 to 10 atmospheres absolute, other inert hydrocarbons or inert gases, e.g. nitrogen or steam, may be present and the ammonia/hydrocarbon volume ratio may be from 0À5: 1 to 12: 1. The nitrile produced may be phthalonitrile, terephthalonitrile, benzonitrile, acrylonitrile or methacrylonitrile; toluonitrile, acetonitrile or propionitrile may also be obtained.