System and method for preparing cycloalkanone

A system for preparing cycloalkanone, comprising:

• an oxidization unit for allowing cycloalkane to be in contact with an oxygen-containing gas for carrying out an oxidization reaction to form a mixture comprising ketone, alcohol and unreacted cycloalkane;
• a mixing unit for mixing alkali metal hydroxide or alkali metal carbonate with the mixture to form a mixed solution;
• a separation unit for separating the mixed solution into a first organic phase solution comprising 25 to 45 wt % of cycloalkanone, 15 to 35 wt % of cycloalkanol, 1 to 20 wt % of water and 100 to 20000 ppm of alkali metal ions, based on a total weight of the first organic phase solution, and a first aqueous phase solution;
• an extraction unit for using water to extract the first organic phase solution to obtain a second organic phase solution comprising 30 to 50 wt % of cycloalkanone, 20 to 40 wt % of cycloalkanol, 1 to 7 wt % of water and less than 80 ppm of alkali metal ions, based on a total weight of the second organic phase solution, and a second aqueous phase solution having an alkalinity of 100 to 2000 meq/kg;
• and
• a distillation unit for separating the cycloalkanone from the second organic phase solution.