Method for producing adipic acid and cyclohexanone oxime from cyclohexane

A method for producing adipic acid and cyclohexanone oxime from cyclohexane, comprising:

• (1) subjecting cyclohexane and NOx to catalytic or non-catalytic oxidation-nitration reaction to produce a first reaction mixture containing adipic acid, nitrocyclohexane and by-product A;
• and separating adipic acid and nitrocyclohexane from the first reaction mixture;
• wherein the NOx is a mixture of molecular oxygen and one or more of N2O, NO, NO2N2O3, N2O4 and N2O5, and x represents a ratio of the number of O atoms to the number of N atoms in the NOx;
• and the by-product A is 1-nitro-1-cyclohexene, cyclohexyl nitrate, glutaric acid, succinic acid, cyclohexanone, cyclohexanol or a combination thereof;
• (2) subjecting the nitrocyclohexane obtained in the step (1) to catalytic hydrogenation with hydrogen to produce cyclohexanone oxime and cyclohexylamine;
• and separating cyclohexanone oxime from cyclohexylamine;
• (3) subjecting the cyclohexylamine obtained in the step (2) to partial oxidation with molecular oxygen under the action of a catalyst to obtain a second reaction mixture containing cyclohexanone oxime and by-product B, wherein cyclohexylamine is absent or present in the second reaction mixture;
• and the by-product B is water, hexamethyleneimine, cyclohexanone, nitrocyclohexane, N-cyclohexyl hexamethyleneimine, dicyclohexylamine or a combination thereof;
• and
• (4-1) without separation, or after separating part or all of water from the second reaction mixture, subjecting the second reaction mixture to simultaneous hydrogenation and amination in the presence of H2 and NH3 under the action of a catalyst, or sequentially to hydrogenation with H2 and amination with NH3 under the action of a catalyst, followed by separation to obtain cyclohexanone oxime;
• or
• (4-2) without separation, or after removing part or all of water from the second reaction mixture by distillation, under the action of a catalyst, subjecting the second reaction mixture to hydrogenation with H2 followed by separation to obtain cyclohexanone oxime.