A method for the regeneration of used lubricating oils to produce lubricant base oils includes the steps of (a) removing resin and impurities by distillation, (b) catalytic oxidation treatment and (c) adsorption process. The method can efficiently reduce the color, metal ions, and sulfur content under mild reaction conditions at low cost and obtain high yield of regenerated oil above 85 wt. %.

The present invention relates to a method for reconditioning bearing lubricants that can be used in equipment for metal working, in which cooling lubricant that can be used in equipment for metal working is separated from the bearing lubricant. In addition the invention relates to a bearing lubricant for use in the method according to the invention.

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.

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.

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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. The separate processing can allow for selection of conditions for forming lubricant fractions, such as bright stock fractions, that have a cloud point that is lower than the pour point.

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.

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. The initial stage can optionally include a bulk hydrotreating catalyst to assist with increasing the space velocity in the initial stage.

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.

An apparatus includes a lubricating oil tank storing a lubricating oil. An oil separator separates the lubricating oil from a working fluid discharged from an expander of a waste heat recovery system. A lubricating oil return conduit is connected between the oil separator and the lubricating oil tank. A working fluid return conduit is connected between the lubricating oil tank and the oil separator. A vaporizer unit is installed in the lubricating oil tank to vaporize a liquefied working fluid mixed with the separated lubricating oil in the lubricating oil tank.

The present invention relates to a process for regenerating a used lubricant composition, especially used for regenerating an engine drain oil, comprising the steps of: fractionating said used lubricant composition in a countercurrent fractional distillation column with a countercurrent flow of supercritical carbon dioxide (sCO.sub.2), wherein said used lubricant composition and supercritical CO.sub.2 are fed in the countercurrent column with a ratio of the sCO.sub.2 flow rate on used lubricant flow rate ranging from 15 to 50; and recovering the regenerated oil extracted within the supercritical CO.sub.2.

It further relates to a process for preparing a lubricant composition from a regenerated base oil obtained according to the invention.