A liquid composition for use in purifying an oil contains a polar polymer, a surface active hydrotrope/solubilizer, and a co-tenside. The polar polymer may be a polyalkylene glycol, such as polyethylene glycol. The hydrotrope/solubilizer may be an anionic sulfonic acid, a phosphate ester-based substance or a non-ionic surfactant from the poly-glycoside family. The co-tenside may be at least one amphoteric co-surfactant, such as sodium caprylimino dipropionate.

Disclosed is a method of treating a used hydrocarbon lubricant of ISO Viscosity Grade 46 or higher comprising oxidation products that adversely affect lubricant performance. The hydrocarbon lubricant has a Group II hydrocarbon oil or Group III hydrocarbon oil, optionally one or more lubricant additives, and an amount of varnish. The hydrocarbon lubricant is free of zinc-containing additives. The method comprises adding to the used hydrocarbon lubricant from about 2 percent by weight to about 20 percent by weight of a polyhydroxy polypropylene oxide homopolymer that has a hydroxyl number of from about 12 mg KOH/g to about 58 mg KOH/g as measured according to ASTM D4274.

A methodology for cleaning and upgrading any kind of tires (cars, motorcycles, trucks, etc.), any kind of waste lubricants (internal combustion engines, industrial parts), any kind of oils as well as plant and animal fats by means of removal of the inorganic elements (potassium, sodium, chlorine, sulfur, phosphorus and heavy metals such as Pb, Cu, Cd, Zn, Hg, Mn, etc.) and the simultaneous addition of new such as calcium, magnesium and ammonium, in order to produce a clean and upgraded rubber material, lubricant as well as fat/oil, which can be used as raw material in thermochemical conversion processes such as flash (t<1 sec)/fast pyrolysis.

In a method for reconditioning an industrial oil and in an oil recovery system therefor, a used industrial oil is reconditioned by adding a liquid separation booster to the used industrial oil, and then the separation booster with attracted impurities is separated from the used industrial oil while leaving at least one specific additive in the oil. The separation booster is designed to attract impurities in the used oil while not attracting at least one specific additive in the oil.

Used lubricating oils are fed to a dehydration/fuel stripping unit to create de-watered/defueled feedstock which is fed to a Vacuum Distillation Column (VDC) to remove and send lighter fractions for processing into base oil. Vacuum Tower Asphalt Extender (VTAE) is collected from the Vacuum Distillation Bottom (VDB) of the VDC and fed to a Solvent Deasphalting unit (SDA) along with a hydrocarbon solvent, to create a Concentrated Asphaltene Polymer Residue (CAPR) containing concentrations of the depleted polymer additives and wear metals. In particular embodiments, the CAPR is used to create relatively high-grade asphalt binders suitable for paving applications.

Sustainable lubricant compositions made from recycled thermoplastic polyesters and other reclaimed or biorenewable reactants and a method of formulating them are disclosed. The lubricant compositions comprise a polyester base oil, which incorporates recurring units from a digested thermoplastic polyester, a low-molecular-weight polyol, and C.sub.8-C.sub.24 fatty acid. The base oil has a number-average molecular weight within the range of 300 to 5000 g/mol, a hydroxyl value less than 50 mg KOH/g, and a viscosity at 40 C. less than 5000 cSt. Some of the lubricant compositions comprise the polyester base oil and one or more additives including anti-wear agents, corrosion inhibitors, antioxidants, thickeners, detergents, and the like. The lubricants have properties that rival those of commercial products made from nonrenewable hydrocarbon blends or polyol esters and are useful for many practical applications such as internal combustion engine oils, gear lubrication oils, hydraulic oils, compressor oils, metal working fluids, and lubricating greases.

The present invention relates to a pre-hydrotreatment and purification method for waste lubricating oil, the method comprising the following steps: mechanical impurities are removed from waste lubricating oil, and then the oil is subjected to flash distillation to separate free water and a portion of light hydrocarbons; a bottom product of the flash distillation column is mixed with hydrogen and a self-sulfurizing oil-soluble transition metal catalyst, and then enters a slurry bed reactor for pre-hydrotreatment; a gas product obtained by performing separation on a reaction effluent is subjected to adsorption purification and then enters a hydrogen recycle compressor for cyclic use; a liquid product obtained by performing separation on a reaction effluent is subjected to hydrocyclone separation and solvent washing to remove solid residue, and finally a purified lubricating oil component is obtained. The method of the present invention has such advantages as simple processing procedures, a high non-ideal component conversion rate, a high oil liquid yield, and good quality. In addition, the oil-soluble catalyst features simple dispersion, no need for vulcanization, a small catalyst adding amount, high low-temperature hydrogenation activity, and is capable of effectively preventing the coking that could occur during a process of preheating the waste lubricating oil, markedly extending the operational lifespan of a waste lubricating oil hydrogen treatment device.

A method for reducing color in used lubricating oil. The method comprises combining: (i) a used lubricating oil; (ii) an alkali metal borohydride; and (iii) a bisulfite or metabisulfite salt.

Proposed is a process of producing a high-quality lube base oil using a refined oil fraction obtained from waste lubricant as a feedstock. The process includes purifying waste lubricant to obtain a refined oil fraction, pretreating the refined oil fraction, and blending the pretreated refined oil fraction with unconverted oil (UCO), before or after vacuum distillation and catalytic dewaxing of the unconverted oil, or between the vacuum distillation and the catalytic dewaxing of the unconverted oil.

Systems and methods for varnish abatement and removal from in-service fluids and components of an industrial lubricated system. The systems and methods may include adding an effective amount of a solubility enhancer to the in-service fluid, and contacting the mixture with a medium having acrylamide or styrenic functionality to remove contaminants from the mixture. Systems may include a medium circuit having a medium pump and a medium component and a solubility enhancer reservoir arranged to dispense solubility enhancer to the reservoir. Methods may include pre-conditioning the in-service fluid before adding solubility enhancer.