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 are provided for block operation during lubricant and/or fuels production from deasphalted oil. During block operation, a deasphalted oil and/or the hydroprocessed effluent from an initial processing stage can be split into a plurality of fractions. The fractions can correspond, for example, to feed fractions suitable for forming a light neutral fraction, a heavy neutral fraction, and a bright stock fraction, or the plurality of fractions can correspond to any other convenient split into separate fractions. The plurality of separate fractions can then be processed separately in the process train (or in the sweet portion of the process train) for forming fuels and/or lubricant base stocks. This can allow for formation of unexpected base stock compositions.

The present invention relates to a metal compound of calixarene not containing sulfur and dispersible in oil, which can be partially salified, or neutral, or basic or overbased, said calixarene having general formula (I) in which: a) R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently selected from hydrogen, or a group containing carbon and hydrogen, or a group containing in addition to carbon and hydrogen also heteroatoms, provided that said heteroatoms are not sulfur; b) one of the two substituents R.sub.5 and R.sub.6 is hydrogen, while the other may be selected from hydrogen, or a linear or branched alkyl with a number of carbon atoms between 1 and 6, preferably methyl, ethyl, 1-propyl, 2-propyl, n-butyl, sec-butyl, more preferably methyl or ethyl; c) n is the number of units of the calixarene ring and is comprised in the range between 4 and 16, preferably between 5 and 12; said calixarene being characterized in that in at least one of the n units of the calixarene ring, at least one of the substituents R.sub.1, R.sub.2, R.sub.3 and R.sub.4 contains at least one acid group of carboxylic type available for the reaction with a metal base, with the proviso that said acid group of carboxylic type is not contained in a unit of the calixarene ring derived from salicylic acid. ##STR00001##

Disclosed is a method for the recovery of filtering agents and rolling oil from a mixture containing used rolling oil and filtering agents coated with used rolling oil in which the mixture containing rolling oil and filtering agents is subjected to vacuum distillation under agitation in a reactor equipped with an agitator and vapour precipitator. The vacuum during distillation is regulated with an inert gas flow, the rolling oil is condensed and collected, and a rolling oil which can be reused for rolling and a powder filtering agent which can be reused are obtained.

A method for re-refining used oils comprises contacting feedstock comprising purified used oil with extraction solvent to perform continuous liquid-liquid solvent extraction, to produce an extract stream comprising the extraction solvent and an extract dissolved in the extraction solvent. The feedstock and the extraction solvent are agitated by a variable speed agitator during the solvent extraction at a selected agitation speed. The extract is separated from the extraction solvent and subjected to a continuous flow liquid phase hydrogenation treatment to produce an oil product. A system for performing the method includes a purification unit for purifying the used oil; an extraction column for extracting the extract from the feedstock; and a continuous flow liquid phase hydrogenation unit. The extraction column comprises an agitator configured to agitate the feedstock and the extraction solvent flowing through the extraction column at a variable agitation speed.

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.

The invention relates to a method for lowering the content of polycyclic aromatic hydrocarbons (PAH) in a used lubricant composition, in which said used lubricant composition passes over activated carbon, said method not comprising a solvent extraction step.

A system for recovering gel-mass from a gel-mass-containing waste material. The system includes mangle rolls, a heated accumulator for receiving and melting the gel-mass-containing waste material to provide an oil phase and a non-oil phase; a pumping system; an optional mixer; and a control system.

Systems and methods are provided for block operation during lubricant and/or fuels production from deasphalted oil. During block operation, a deasphalted oil and/or the hydroprocessed effluent from an initial processing stage can be split into a plurality of fractions. The fractions can correspond, for example, to feed fractions suitable for forming a light neutral fraction, a heavy neutral fraction, and a bright stock fraction, or the plurality of fractions can correspond to any other convenient split into separate fractions. The plurality of separate fractions can then be processed separately in the process train (or in the sweet portion of the process train) for forming fuels and/or lubricant base stocks. This can allow for formation of unexpected base stock compositions.

A method for re-refining used oils comprises contacting feedstock comprising purified used oil with extraction solvent to perform continuous liquid-liquid solvent extraction, to produce an extract stream comprising the extraction solvent and an extract dissolved in the extraction solvent. The feedstock and the extraction solvent are agitated by a variable speed agitator during the solvent extraction at a selected agitation speed. The extract is separated from the extraction solvent and subjected to a continuous flow liquid phase hydrogenation treatment to produce an oil product. A system for performing the method includes a purification unit for purifying the used oil; an extraction column for extracting the extract from the feedstock; and a continuous flow liquid phase hydrogenation unit. The extraction column comprises an agitator configured to agitate the feedstock and the extraction solvent flowing through the extraction column at a variable agitation speed.