A method for separating CO.sub.2 from C.sub.2 to C.sub.5 alkanes includes introducing a first stream including C.sub.2 to C.sub.5 alkanes and CO.sub.2 into a first separation zone, the first separation zone including a hydrocarbon solvent, and separating the first stream into a recycle stream and a second stream in the first separation zone. The recycle stream including CO.sub.2 and one or more of CO, H.sub.2, and CH.sub.4, and the second stream including C.sub.2 to C.sub.5 alkanes. The method further includes introducing the second stream into a second separation zone, and separating the second stream into a third stream and a fourth stream, wherein the third stream includes C.sub.2 alkanes and the fourth stream includes C.sub.3 to C.sub.5 alkanes.

A method for separating CO.sub.2 from C.sub.2 to C.sub.5 alkanes includes introducing a first stream including C.sub.2 to C.sub.5 alkanes and CO.sub.2 into a first separation zone, the first separation zone including a hydrocarbon solvent, and separating the first stream into a recycle stream and a second stream in the first separation zone. The recycle stream including CO.sub.2 and one or more of CO, H.sub.2, and CH.sub.4, and the second stream including C.sub.2 to C.sub.5 alkanes. The method further includes introducing the second stream into a second separation zone, and separating the second stream into a third stream and a fourth stream, wherein the third stream includes C.sub.2 alkanes and the fourth stream includes C.sub.3 to C.sub.5 alkanes.

A method for producing methyl methacrylate including: a distillation step including: supplying a reaction solution, which is obtained by subjecting methacrolein, methanol, and molecular oxygen to oxidative esterification in an oxidative esterification reactor and which contains the methyl methacrylate as a reaction product, to a first distillation column located at downstream of the oxidative esterification reactor, extracting a fraction containing the methacrolein and the methanol from a medium section of the first distillation column, and extracting a column bottom liquid containing the methyl methacrylate from a column bottom of the first distillation column, wherein a concentration of the methanol in the column bottom liquid is 1% by mass or more and 30% by mass or less.

The present disclosure discloses a method for extracting a plant essential oil with dual auxiliaries, which includes: using an aromatic plant as a raw material, adding an extracting liquid prepared from the dual auxiliaries and water, stirring evenly for raw material wetting back, then distilling and collecting the essential oil, where the dual auxiliaries include a component A and a component B, the component A includes at least one of choline chloride and betaine, and the component B includes at least one of a natural acid, an amine, an alcohol and a saccharide.

Systems and methods for extracting a compound of interest from plant material, such as acannabidiol (CBD) from cannabis, are provided. Particularly, the disclosed systems and methods utilize a crude oil to separate water, fats, and proteins prior to preparation of a CBD distillate. The systems and methods are operable with conventional solvents containing between about 5 wt % and about 8 wt % water.

A saline feed stream flows into a liquid-liquid extraction system; and a volatile organic solvent flows through a main compressor. The compressed volatile organic solvent then flows through a solvent regenerator, which can be a heat exchanger or a combination of a vaporization device and a condenser, to cool the volatile organic solvent. The cooled volatile organic solvent in liquid phase then flows into the liquid-liquid extraction system, where the saline feed stream contacts the volatile organic solvent to selectively extract water from the saline feed stream into the volatile organic solvent, producing a concentrated brine and an organic-rich mixture of water and the volatile organic solvent. The organic-rich mixture flows from the liquid-liquid extraction system into the solvent regenerator, where the organic-rich mixture is heated to produce an organic-rich vapor and desalinated water; and the organic-rich vapor is recycled as volatile organic solvent back into the liquid-liquid extraction system.

A system of concentrating and separating waste solvent liquid includes a distillation tower, an extracting distillation unit, an extract agent recovery unit, and a vapor permeation film unit. The scheme of centrifugal distillation is specifically employed to collocate with vapor permeation to effectively concentrate the content of isopropanol in the waste solvent liquid to generate a final produce with ultra high concentration of isopropanol, and constantly recovers the extract agent. The system is able to be quickly settled to a steady state of operation with low power consumption because the extracting distillation unit has smaller size. Since no liquid is left in the extract agent recovery unit, operation risk is greatly reduced. In addition, the input feed is almost processed, overall efficiency is thus improved. The vapor permeation film unit further removes considerably little content of water from the organic solvent to increase the content of isopropanol up to 99.9% or more.

A system of concentrating and separating waste solvent liquid includes a distillation tower, an extracting distillation unit, an extract agent recovery unit, and a vapor permeation film unit. The scheme of centrifugal distillation is specifically employed to collocate with vapor permeation to effectively concentrate the content of isopropanol in the waste solvent liquid to generate a final produce with ultra high concentration of isopropanol, and constantly recovers the extract agent. The system is able to be quickly settled to a steady state of operation with low power consumption because the extracting distillation unit has smaller size. Since no liquid is left in the extract agent recovery unit, operation risk is greatly reduced. In addition, the input feed is almost processed, overall efficiency is thus improved. The vapor permeation film unit further removes considerably little content of water from the organic solvent to increase the content of isopropanol up to 99.9% or more.

A system of concentrating and separating waste solvent liquid includes a distillation tower, an extracting distillation unit, an extract agent recovery unit, and a vapor permeation film unit. The scheme of centrifugal distillation is specifically employed to collocate with vapor permeation to effectively concentrate the content of isopropanol in the waste solvent liquid to generate a final produce with ultra high concentration of isopropanol, and constantly recovers the extract agent. The system is able to be quickly settled to a steady state of operation with low power consumption because the extracting distillation unit has smaller size. Since no liquid is left in the extract agent recovery unit, operation risk is greatly reduced. In addition, the input feed is almost processed, overall efficiency is thus improved. The vapor permeation film unit further removes considerably little content of water from the organic solvent to increase the content of isopropanol up to 99.9% or more.

A process for recovering monomers and solvent present in a waste stream including the steps of: (a) providing a waste feed stream containing monomers, solvent and impurities; (b) subjecting the waste feed stream of step (a) to a separation process under conditions for separating the monomers and solvent from the impurities of the waste stream; (c) recovering the monomers and solvent in one or more streams; and (d) passing the one or more of the monomer and solvent streams from step (c) to further processing.