Systems and methods are provided for performing solvent dewaxing using a dewaxing solvent that is not fully miscible with the feed being dewaxed. It has been unexpectedly discovered that by operating with a ketone solvent mixture that is beyond the miscibility limit by a small amount, the rate of solvent dewaxing can be substantially increased. Additionally, the difference between the filtration temperature during solvent dewaxing and the pour point of the resulting dewaxed product is unexpectedly reduced. The dewaxing solvent beyond the miscibility limit can correspond to, for example, a solvent mixture where the weight percent of methyl ethyl ketone is beyond the miscibility limit by 0.1 vol % to 5.0 vol %.

Systems and methods are provided for performing solvent dewaxing using a dewaxing solvent that is not fully miscible with the feed being dewaxed. It has been unexpectedly discovered that by operating with a ketone solvent mixture that is beyond the miscibility limit by a small amount, the rate of solvent dewaxing can be substantially increased. Additionally, the difference between the filtration temperature during solvent dewaxing and the pour point of the resulting dewaxed product is unexpectedly reduced. The dewaxing solvent beyond the miscibility limit can correspond to, for example, a solvent mixture where the weight percent of methyl ethyl ketone is beyond the miscibility limit by 0.1 vol % to 5.0 vol %.

Systems and methods are provided for performing solvent dewaxing using a dewaxing solvent that is not fully miscible with the feed being dewaxed. It has been unexpectedly discovered that by operating with a ketone solvent mixture that is beyond the miscibility limit by a small amount, the rate of solvent dewaxing can be substantially increased. Additionally, the difference between the filtration temperature during solvent dewaxing and the pour point of the resulting dewaxed product is unexpectedly reduced. The dewaxing solvent beyond the miscibility limit can correspond to, for example, a solvent mixture where the weight percent of methyl ethyl ketone is beyond the miscibility limit by 0.1 vol % to 5.0 vol %.

Systems and methods are provided for performing solvent dewaxing using a dewaxing solvent that is not fully miscible with the feed being dewaxed. It has been unexpectedly discovered that by operating with a ketone solvent mixture that is beyond the miscibility limit by a small amount, the rate of solvent dewaxing can be substantially increased. Additionally, the difference between the filtration temperature during solvent dewaxing and the pour point of the resulting dewaxed product is unexpectedly reduced. The dewaxing solvent beyond the miscibility limit can correspond to, for example, a solvent mixture where the weight percent of methyl ethyl ketone is beyond the miscibility limit by 0.1 vol % to 5.0 vol %.

A method for preparing an environmental-friendly rubber oil, including: conducting extraction in an extraction tower, where a primary extraction solvent is introduced into an upper section of the extraction tower, a raw oil is introduced into a middle-lower section of the extraction tower, and a secondary extraction solvent is introduced into a lower section of the extraction tower; subjecting a material at a bottom of the extraction tower to solvent recovery to obtain a secondary extract oil; mixing a substance flowing out from a top of the extraction tower, a solubilizer and a part of the primary extraction solvent, cooling to 15 C. to 10 C., and filtering to obtain a wax paste and a filtrate; subjecting the wax paste to heating evaporation and solvent recovery to obtain a wax; and subjecting the filtrate to heating evaporation and solvent recovery, obtaining the environmental-friendly rubber oil.

A method for preparing an environmental-friendly rubber oil, including: conducting extraction in an extraction tower, where a primary extraction solvent is introduced into an upper section of the extraction tower, a raw oil is introduced into a middle-lower section of the extraction tower, and a secondary extraction solvent is introduced into a lower section of the extraction tower; subjecting a material at a bottom of the extraction tower to solvent recovery to obtain a secondary extract oil; mixing a substance flowing out from a top of the extraction tower, a solubilizer and a part of the primary extraction solvent, cooling to 15 C. to 10 C., and filtering to obtain a wax paste and a filtrate; subjecting the wax paste to heating evaporation and solvent recovery to obtain a wax; and subjecting the filtrate to heating evaporation and solvent recovery, obtaining the environmental-friendly rubber oil.

A method for dewaxing of an extract oil and a rubber oil is provided, where a composite solvent including a polar solvent and a solubilizer is used as a dewaxing solvent, the polar solvent is N-methylpyrrolidone (NMP), and the solubilizer is at least one selected from the group consisting of benzene, toluene, and xylene. The method includes: mixing the composite solvent with the extract oil or the rubber oil at a temperature higher than a precipitation temperature of a wax, subjecting a resulting mixture to cooling crystallization and filtration to obtain a wax paste and a filtrate, and then independently subjecting the wax paste and the filtrate to solvent recovery by heating evaporation to obtain a wax and a dewaxed oil, respectively.

A method for dewaxing of an extract oil and a rubber oil is provided, where a composite solvent including a polar solvent and a solubilizer is used as a dewaxing solvent, the polar solvent is N-methylpyrrolidone (NMP), and the solubilizer is at least one selected from the group consisting of benzene, toluene, and xylene. The method includes: mixing the composite solvent with the extract oil or the rubber oil at a temperature higher than a precipitation temperature of a wax, subjecting a resulting mixture to cooling crystallization and filtration to obtain a wax paste and a filtrate, and then independently subjecting the wax paste and the filtrate to solvent recovery by heating evaporation to obtain a wax and a dewaxed oil, respectively.