Reclaiming used lubricating oils

摘要: An integrated process universally applicable for the reclaiming of used lubricating oils, regardless contaminants or previous additive systems contained therein, is provided to produce an intermediate low-ash oil a high-grade lube stock which comprises (a) contacting with aqueous ammonium salt treating agent, (b) removing major portion water, (c) separating phase from resulting residual product, (d) subjecting separated hydrotreating and thereafter (e) stripping hydrotreated stock. Optionally product step can be recovered use as fuel oil, in grease formulations, preparation some types formulations.