METHOD FOR REGENERATING USED OILS BY DEMETALLIZATION AND DISTILLATION

摘要

The present invention refers to a method for the regeneration of used petroleum oils which comprises the following steps:
(a) demetallization of the used mineral oil by means of chemical treatment of said oil with an aqueous solution of a chemical reagent containing anions which form low solubility salts with the metals of the oil, followed by the separation of the demetallized oil;
(b) distillation of the demetallized oil obtained in step (a) at atmospheric pressure and in the presence of alkaline hydroxides; and
(c) distillation of the bottom liquid obtained in the atmospheric distillation in step (b) under vacuum and in the presence of alkaline hydroxides to obtain lubricant bases.