In the second stage of the KA oxidation to adipic acid, products from other processes can also be employed, e. g., pure cyclohex-anol as obtained from the liquid-phase hydrogenation of phenol with a Pd catalyst at 150 'C and 10 bar. In 199 1 the production capacity for adipic acid from phenol was 15000 tonnes, or about 2% of total adipic acid capacity, in the USA. In Western Europe, only 6% of the adipic acid was still produced from phenol in 1991; in Japan, this route is no longer used.