Abstract: The thermal decomposition of N-methyl-2-pyrrolidone is minimized by the addition of minor amounts of water thereto prior to its being heated to temperatures in excess of 500.degree. F. This is of particular importance in processes using N-methyl-2-pyrrolidone as an extraction solvent to remove aromatics from mixtures of aromatic and non-aromatic hydrocarbons and wherein the N-methyl-2-pyrrolidone is recovered from the extracted fractions by thermal means such as flash evaporation and distillation.

Abstract: A multi-stage process for the solvent extraction of isoprene or cyclopentadiene from a mixed feed stock containing the same, piperylene and C-5 saturated and olefinic hydrocarbons is disclosed wherein the feed stock is contacted with N-formyl morpholine and C-5 saturated and olefinic hydrocarbons are separated therefrom in a first stage, the solvent, piperylene and cyclopentadiene present in the feed stock are separated from the isoprene in a second stage, and the solvent is recovered and recycled to the second stage.

Abstract: Asphaltic material is dissolved by contact with a solvent composition for a time sufficient to dissolve the asphaltic material wherein the solvent composition is comprised of a liquid heavy aromatic solvent having a high flash point and a fused heterocyclic ring compound or compounds soluble in the heavy aromatic solvent. In another embodiment, the asphaltic material is the binder material of a degraded organic residue whereby dissolution of the asphaltic material enables the convenient disintegration of the degraded organic residue. In still another embodiment, the solvent composition is the oil phase of an oil-water emulsion.

Abstract: Process for recovering highly pure aromatic substances from mixtures of hydrocarbons which contain in addition to the aromatic substances, large amounts of non-aromatic substances by liquid-liquid extraction in combination with an after arranged extractive distillation whereby the liquid-liquid extraction of the starting hydrocarbon mixture is carried out under such conditions that the resulting extract contains substantially the total amount of the aromatic substances and a portion of the non-aromatic substances, introducing this extract into an after arranged extractive distillation for further separating said extract whereby the sump product (extract phase) formed is drawn off and introduced into an after arranged distillation column where it is separated into an aromatic and a solvent fraction, while the head product of the extractive distillation (raffinate phase) is reintroduced into the bottom of the extractor for liquid-liquid extraction thereof, wherein there is used in both of the extracting stages,

Abstract: N-methyl-2-pyrrolidone is recovered from the raffinate and extract phases produced by its use in hydrocarbon extraction processes, particularly lube oil extraction, through the use of flash evaporation and/or distillation followed by gas stripping. Water buildup in the recovered solvent is prevented by employing solvent dehydration means in the solvent recovery line after gas stripping. Proper control of process parameters enables the dehydration means to remove excess water without requiring additional heat input to the process.

Abstract: Asphaltic material is dissolved by contact with a solvent composition for a time sufficient to dissolve the asphaltic material wherein the solvent composition is comprised of a liquid heavy aromatic solvent having a high flash point and a fused heterocyclic ring compound or compounds soluble in the heavy aromatic solvent. In another embodiment, the asphaltic material is the binder material of a degraded organic residue whereby dissolution of the asphaltic material enables the convenient disintegration of the degraded organic residue. In still another embodiment, the solvent composition is the oil phase of an oil-water emulsion.

Abstract: A multi-stage process for the solvent extraction of butadiene from a mixed feed stock containing butadiene, C-4 saturated and olefinic hydrocarbons and acetylenic compounds is disclosed wherein the feed stock is contacted with N-formyl morpholine and C-4 saturated and olefinic hydrocarbons are separated therefrom in a first stage and, in a second stage, the solvent and acetylenic compounds present in the feed stock are respectively separated from one another.

Abstract: Morpholinones are efficient selective solvents for aromatic hydrocarbons from hydrocarbon mixtures containing same. For example, N-methyl-3-morpholinone is an efficient selective solvent for benzene, toluene, and xylene from a hydrocarbon stream obtained from a catalytic reformer.

Abstract: Styrene of exceptional purity is separated from a mixture of hydrocarbons including it, xylenes, saturated and olefinic hydrocarbons and ethyl benzene by means of a two-step extractive distillation process through the use of a high boiling polar solvent such as N-formyl morpholine in admixture with an amount of water in the range of from 1% to 30% by weight.