Patent · US Expired

Method for reclaiming waste lubricating oils

US4073720A · kind A · utility

18Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 22, 1976
Grant dateFeb 14, 1978
Priority date
Expiry dateOct 22, 1996

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10M175/005
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A method for purifying and reclaiming used lubricating oils containing additives such as detergents, antioxidants, corrosion inhibitors, extreme pressure agents and the like and other solid and liquid contaminants by preferably first vacuum distilling the used oil to remove water and low-boiling contaminants, and treating the dried oil with a solvent mixture of butanol, isopropanol and methylethyl ketone which causes the separation of a layer of sludge containing contaminants, unspent additives and oxidation products. After solvent recovery, the desludged oil is then subjected to conventional lubricating oil refining steps such as distillation followed by decolorization and deodorization.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.