A process for converting a 1,1-diarylalkane, such as a 1,1-bis(alkylphenyl)alkane, to the corresponding diarylketone which involves oxidizing the 1,1-diarylalkane using critical amounts of 1,1-diarylalkane, nitric acid and water. The reaction product obtained as a result of such oxidation of a 1,1-bis(alkylphenyl)alkane can be further subjected to reaction with additional nitric acid at elevated temperatures in a second stage to convert each of the nuclear alkyl groups on the alkyl-aromatic charge to carboxyl groups and the dilute nitric acid remaining can be employed in the first stage as oxidant.