Viscosity reduction of oils by sonic treatment

A process for decreasing the viscosity of crude oils and residuum comprising the steps of:

• (a) contacting the crude oil or crude oil residuum with an effective amount of an acid selected from the group consisting of sulfuric acid, hydrochloric acid, perchloric acid, acetic acid, para-toluene sulfonic acid, alkyl toluene sulfonic acids, mono di and trialkyl phosphoric acids, C3 to C16 organic carboxylic acids, succinic acid , petroleum naphthenic acid and mixtures thereof,
• (b) sonicating said crude oil or crude oil residuum and said acid at a temperature and for a time sufficient to decrease the viscosity of said crude oil or residuum.