Method for producing base lubricating oil from oils recovered from combustion engine service

Abstract

A method for producing ILSAC GF5 or higher compatible oils from used oil, comprising separating material having a boiling point less than about 350° F. from recovered oil to produce de-volatized oil fraction and light oil fraction. Separating material with a boiling point greater than about 350° F. and less than about 650° F. from the de-volatized oil fraction to produce fuel oil fraction and heavy oil fraction. Separating material with a boiling point greater than about 1200° F. from the heavy oil fraction to produce partially purified oil fraction and residual fraction. Treating the partially purified oil fraction to separate it into purified oil fraction and contaminant fraction. Hydrogenating the contaminant fraction to remove predetermined compounds, further saturating the fraction and thereby creating a saturated oil fraction. Fractionating the saturated oil stream to produce one or more of naphtha fraction, diesel oil fraction and base oil fraction.

What is claimed is: 
     
         1 . A method for efficiently producing a high yield of ILSAC GF5 or higher compatible oils from the recovery and upgrade of oil derived from modern electric, hybrid, turbocharged, and high efficiency gasoline and diesel engines, the method comprising:
 a) separating at least a portion of material having a boiling point less than about 350° F. from recovered oil to produce a de-volatized oil fraction and a light oil fraction;   b) separating at least a portion of material with a boiling point greater than about 350° F. and less than about 650° F. from the de-volatized oil fraction to produce a fuel oil fraction and a heavy oil fraction;   c) separating at least a portion of material with a boiling point greater than about 1200° F. from the heavy oil fraction to produce a partially purified oil fraction and a residual fraction;   d) treating the partially purified oil fraction to separate it into a purified oil fraction and a contaminant fraction;   e) hydrogenating the contaminant fraction to remove predetermined compounds, further saturating the fraction and thereby creating a saturated oil fraction; and   g) fractionating the saturated oil stream to produce one or more of a naphtha fraction, a diesel oil fraction and a base oil fraction.   
     
     
         2 . The method of  claim 1  wherein the base oil faction consists of oils that met at least one of American Petroleum Institute standards SJ/SL/SM/SN or higher or CG-4/CH-4/CI-4/CJ-4 or higher specifications when the base oil was first put into service. 
     
     
         3 . The method of  claim 1  wherein the light oil fraction is separated from the de-volatized oil fraction by at least one of distillation, vacuum distillation, evaporation, filtration, ultrafiltration, extractant extraction, extraction, centrifugation, absorption, and adsorption. 
     
     
         4 . The method of  claim 1  wherein the light oil fraction is separated from the de-volatized oil fraction by at least one of atmospheric or vacuum distillation. 
     
     
         5 . The method of  claim 1  wherein the fuel oil fraction is separated from the heavy oil fraction by at least one of distillation, vacuum distillation, evaporation, filtration, ultrafiltration, extractant extraction, extraction, centrifugation, absorption, and adsorption. 
     
     
         6 . The method of  claim 1  wherein the fuel oil fraction is separated from the heavy oil fraction by atmospheric distillation. 
     
     
         7 . The method of  claim 1  wherein the partially purified fraction is separated from the residual oil fraction by at least one of distillation, vacuum distillation, evaporation, filtration, ultrafiltration, extractant extraction, extraction, centrifugation, absorption, and adsorption. 
     
     
         8 . The method of  claim 1  wherein the partially purified fraction is separated from the residual oil fraction by vacuum distillation in an unpacked column. 
     
     
         9 . The method according to  claim 1  whereby the feedstock is treated with an alkali or base to condition the feedstock. 
     
     
         10 . The method according to  claim 9  whereby the alkali or base is one of sodium carbonate, sodium hydroxide, and potassium hydroxide. 
     
     
         11 . The method according to  claim 1  whereby the feedstock is treated to remove water and light hydrocarbons. 
     
     
         12 . The method of  claim 1  wherein the purified oil fraction and the contaminant fraction are separated by at least one of the filtration, ultrafiltration, molecular sieves, extraction, extractant extraction, absorption, and adsorption. 
     
     
         11 . The method of  claim 1  wherein the purified oil fraction and the contaminant fraction are separated by liquid/liquid extraction. 
     
     
         12 . The method of  claim 1  wherein one or more liquids are used including ethanol, diacetone-alcohol, ethylene-glycol-mono(low alkyl) ether, di-ethylene-glycol, diethylene-glycolmono(low alkyl) ether, o-chlorophenol furfural, acetone, formic acid, 4-butyrolacetone, low-alkyl-ester of low mono- and dicarbonic acids, dimethylformamide, 2-pyrrolidone and N-(low alkyl)2-pyrrolidone, N-methyl-2-pyrolodone, epi-chlorohydrin, dioxane, morpholine, low-alkyl- and amino(low-alkyl)morpholine, benzonitrile and di-(low-alkyl)sulfoxide and phosphonate. 
     
     
         13 . The method of  claim 1  wherein two or more liquids are used of ethanol, diacetone-alcohol, ethylene-glycol-mono(low alkyl) ether, di-ethylene-glycol, diethylene-glycolmono(low alkyl) ether, o-chlorophenol furfural, acetone, formic acid, 4-butyrolacetone, water, aqueous salts, low-alkyl-ester of low mono- and dicarbonic acids, dimethylformamide, 2-pyrrolidone and N-(low alkyl)2-pyrrolidone, N-methyl-2-pyrolodone, mono or poly protic acids, mineral acids, carboxylic acids, hydroxide bases, carbonate bases, mineral bases, epi-chlorohydrin, dioxane, morpholine, low-alkyl- and amino(low-alkyl)morpholine, benzonitrile and di-(low-alkyl)sulfoxide and phosphonate. 
     
     
         14 . The method according to  claim 12  wherein at least one of the liquids is the extractant N-methyl 2 pyrolidone. 
     
     
         15 . The method of  claim 1  wherein the one or more of the oil streams is suitable for use in ILSAC GF4 or higher applications. 
     
     
         16 . The method according to  claim 1  wherein the contaminant fraction consists of polars, aromatics, heteroatoms, unsaturates, and olefines. 
     
     
         17 . The method according to  claim 1  wherein the liquid/liquid extraction is under conditions wherein the extractant is at least partially miscible in the oil. 
     
     
         18 . The method of  claim 11  wherein the liquid/liquid extraction is undertaken between 140° F. and 200° F. 
     
     
         19 . The method of  claim 11  wherein the liquid/liquid extraction is undertaken with an extractant treat ratio in excess of 3:1. 
     
     
         20 . The method of  claim 11  wherein the liquid/liquid extraction is undertaken in an extraction column designed to limit entrainment and enable good separation of the oil and extractant phases. 
     
     
         21 . The method of  claim 11  wherein the liquid/liquid extraction is undertaken in a packed column. 
     
     
         22 . The method of  claim 11  wherein the residence time is sufficient to enable efficient extractant oil contact and good phase disengagement. 
     
     
         23 . The method according to  claim 11  whereby a phase catalyst is used to enhance extraction. 
     
     
         24 . The method of  claim 1  wherein the hydrogenation process consists of one or more of hydrotreating, hydrofinishing, alkylating, or molecular reforming. 
     
     
         25 . The method of  claim 24  wherein hydrogenation is undertaken using hydrogen gas at a temperature from about 500 to about 1200° F. and at a pressure from about 100 to about 2000 psig in the presence of a catalyst containing group VB, BIB and VIII of the periodic table, metal components and compounds thereof supported on a suitable. 
     
     
         26 . The method according to  claim 1  wherein the purified oil fraction and the saturated oil fraction are combined and then fractionated into one or more of a light oil fraction, a diesel oil fraction and lube oil fractions. 
     
     
         27 . The method according to  claim 1  whereby the residence time of the non-volatized portion of the feed to each step has a residence time within the vessels of the step of between 5 minutes and 5 hours.