Abstract: Basic nitrogen compounds (BNC) are selectively removed from solvent extracted oils by adsorption of said BNC's by solid acidic polar adsorbents. The oils are extracted using any of the common extraction solvents, such as furfural, phenol, SO.sub.2, N-methyl-2-pyrrolidone (NMP), preferably NMP. The resulting raffinate, which contains the desirable oil fraction, has the BNC's present therein removed by adsorption thereof onto an adsorbent, characterized as being a solid, polar acidic adsorbent, exemplified by silica-alumina, a high alumina base amorphous cracking catalyst (such as manufactured by Ketjen/Akzo) and crystalline zeolite (such as H-Y zeolites) are effective adsorbents. The adsorbents may additionally contain fluorine or may contain up to 30 weight percent water. The adsorbents are regenerated by either purging with hydrogen at elevated temperature and pressure, or by washing the BNC saturated adsorbent with extraction process extraction solvent, such as NMP.

Abstract: Waxy oil distillates, preferably waxy petroleum oil distillates, most preferably waxy lube refrigerator, turbine, transformer or other speciality oil distillates which contain appreciable amounts of aromatics and polar molecule contaminants can have wax and aromatics/polars simultaneously and continuously removed from said oil using an adsorbent/desorbent system. The adsorbent system employs a combination of large pore polar adsorbent/hydrophobic molecular sieves. The desorbent system utilizes a combination small diameter polar solvent/large diameter non-polar solvent to regenerate the loaded adsorbent.

Abstract: Used oils, especially used lubricating oils which are normally considered waste and are discarded or burned, are reclaimed for reuse by a re-refining procedure involving the steps of:(a) heat soaking the used oil;(b) distilling the heat soaked oil;(c) passing the distillate through a guard bed of activated material;(d) hydrotreating the guard bed treated distillate under standard hydrotreating conditions.If the used oil to be re-refined contains a quantity of water and/or fuel fraction which the practioner considers sufficiently large to be detrimental, the used oil may be subjected to a dewatering/defueling step prior to being heat soaked.