We disclose a process for purification of mixed hydrocarbons, suitable for a wide range of contexts such as separating and recovering mixed polymer materials, refining used oils and fuels, recovery of hydrocarbons from used tyres, recovery of hydrocarbons from thermoplastics etc, to yield clean hydrocarbon distillates suitable for use as recycled feedstocks in chemical industries or as low sulphur fuels for motive use, as well as the treatment of crude oils, shale oils, and the tailings remaining after fractionation and like processes. The method comprises the steps of heating the hydrocarbon bearing material thereby to release a gas phase, contacting the gas with an aqueous persulphate electrolyte within a reaction chamber, and condensing the gas to a liquid or a liquid/gas mixture and removing its aqueous component. It also comprises subjecting the reaction product to an electrical field generated by at least two opposing electrode plates between which the reaction product flows; this electrolytic step regenerates the persulphate electrolyte which can be recirculated within the process. The process is ideally applied in an environment at lower than atmospheric pressure, such as less than 14000 Pa. A wide range of mixed materials and hydrocarbons can be separated and treated in this way. Used hydrocarbons such as mixed plastic packaging waste, industrial polymers, pyrolysis oils etc, are typical examples, but there are a wide range of other materials having a hydrocarbon content. One such prime example is a mix of used rubber (such as end-of-life tyres) and used oils (such as engine oils, waste marine oils) etc, which can be pyrolysed together to yield a hydrocarbon liquid which can be treated as above to provide a carbon black residue that has extensive industrial uses.

A method for preparing methyl acrylate comprises heating in a reaction zone a mixture comprising acrylic acid, methanol, and an acid catalyst to react and form a reaction product comprising methyl acrylate which is vaporized with other light components and then fed to a distillation zone. A feed stream entering the reaction zone comprises methanol and acrylic acid in a molar ratio of greater than 1 and less than 2, and a residence time in the reaction zone ranges from 0.25 to 2 hours. A distillate from the distillation zone is condensed and phase-separated to form an organic phase comprising methyl acrylate and an aqueous phase. A portion of the organic phase is returned to the distillation zone as organic reflux. The remainder of the organic phase and the aqueous phase of the distillation zone is fed to an extraction column to form a methanol rich aqueous effluent and an organic effluent comprising methyl acrylate. The organic effluent from the extraction column is purified in a single finishing column, wherein a light ends stream is removed from the top of the finishing column, a bottoms stream is removed from the bottom of the finishing column, and methyl acrylate is removed from a side draw stream.

A method for preparing methyl acrylate comprises heating in a reaction zone a mixture comprising acrylic acid, methanol, and an acid catalyst to react and form a reaction product comprising methyl acrylate which is vaporized with other light components and then fed to a distillation zone. A feed stream entering the reaction zone comprises methanol and acrylic acid in a molar ratio of greater than 1 and less than 2, and a residence time in the reaction zone ranges from 0.25 to 2 hours. A distillate from the distillation zone is condensed and phase-separated to form an organic phase comprising methyl acrylate and an aqueous phase. A portion of the organic phase is returned to the distillation zone as organic reflux. The remainder of the organic phase and the aqueous phase of the distillation zone is fed to an extraction column to form a methanol rich aqueous effluent and an organic effluent comprising methyl acrylate. The organic effluent from the extraction column is purified in a single finishing column, wherein a light ends stream is removed from the top of the finishing column, a bottoms stream is removed from the bottom of the finishing column, and methyl acrylate is removed from a side draw stream.

A system for processing cannabinoids and recovering solvent has a vessel for a mixture of cannabinoids and solvent. A pump forms a vacuum in the system to draw the mixture into a first heat exchanger to pre-heat the mixture. A falling film evaporator receives the mixture from the first heat exchanger, and boils the mixture to form a solvent vapor. The falling film evaporator collects the cannabinoids from the mixture as a crude oil. The first heat exchanger receives the solvent vapor. Heat is transferred to incoming mixture of the system, and cools and condenses the solvent vapor to form solvent condensate and vapor. A second heat exchanger receives and further cools the solvent condensate and vapor to form further condensed solvent and some solvent vapor. The pump receives the further condensed solvent and some solvent vapor and increases pressure to form solvent liquid and recovers solvent liquid for reuse.

The present invention relates to an extraction apparatus for extracting at least one constituent in a substance. The extraction apparatus comprises an extractor, an extraction separator and an extraction condenser. The extractor is used to mix the substance and an extraction fluid, wherein the extraction fluid is a subcritical fluid. The extraction separator is connected to the extractor for receiving and heating the extraction fluid to gasify the extraction fluid and to separate the constituent and the gasified extraction fluid. The extraction condenser is connected to the extraction separator and the extractor for receiving and liquefying the gasified extraction fluid from the extraction separator and sending the liquefied extraction fluid to the extractor.

The present invention relates to an extraction apparatus for extracting at least one constituent in a substance. The extraction apparatus comprises an extractor, an extraction separator and an extraction condenser. The extractor is used to mix the substance and an extraction fluid, wherein the extraction fluid is a subcritical fluid. The extraction separator is connected to the extractor for receiving and heating the extraction fluid to gasify the extraction fluid and to separate the constituent and the gasified extraction fluid. The extraction condenser is connected to the extraction separator and the extractor for receiving and liquefying the gasified extraction fluid from the extraction separator and sending the liquefied extraction fluid to the extractor.

A method for separating aromatic hydrocarbons by an extractive distillation, comprising introducing a hydrocarbon mixture containing aromatic hydrocarbons into the middle of an extractive distillation column (8); introducing an extraction solvent into the upper part of the extractive distillation column; after an extractive distillation, a raffinate containing benzene is discharged from the top of the column, wherein the benzene content is 3-40% by mass, and sent to the lower part of the extraction column (10); the extraction solvent is introduced to the upper part of the extraction column for a liquid-liquid extraction; a raffinate liquid free of aromatic hydrocarbons is discharged from the top of the extraction column; a rich solvent containing benzene is discharged from the bottom of the column and enters the upper-middle part of the extractive distillation column; the rich solvent obtained at the bottom of the extractive distillation column is sent to the solvent recovery column to separate the aromatic hydrocarbons and the solvent. By combining an extractive distillation with a liquid-liquid extraction ingeniously, the method can achieve the separation of aromatic hydrocarbons with a high purity and a high recovery rate, and a significant decrease of the energy consumption in the extraction and separation process.

A method for separating aromatic hydrocarbons by an extractive distillation, comprising introducing a hydrocarbon mixture containing aromatic hydrocarbons into the middle of an extractive distillation column (8); introducing an extraction solvent into the upper part of the extractive distillation column; after an extractive distillation, a raffinate containing benzene is discharged from the top of the column, wherein the benzene content is 3-40% by mass, and sent to the lower part of the extraction column (10); the extraction solvent is introduced to the upper part of the extraction column for a liquid-liquid extraction; a raffinate liquid free of aromatic hydrocarbons is discharged from the top of the extraction column; a rich solvent containing benzene is discharged from the bottom of the column and enters the upper-middle part of the extractive distillation column; the rich solvent obtained at the bottom of the extractive distillation column is sent to the solvent recovery column to separate the aromatic hydrocarbons and the solvent. By combining an extractive distillation with a liquid-liquid extraction ingeniously, the method can achieve the separation of aromatic hydrocarbons with a high purity and a high recovery rate, and a significant decrease of the energy consumption in the extraction and separation process.

An improved process for the recovery of high-purity ethylene-oxide water feed streams to EO purification and MEG reaction units when both are operating in EO plants that incorporate EO Stripper bypass technology, by installing a second lights stripper to exclusively degasify the diluted EO feed to the MEG reactor, thus permitting the use of additional bypassed (gasified) EO absorbate as the diluent and resulting in a substantial increase in the total amount of EO absorbate that can bypass the EO Stripper.

An improved process for the recovery of high-purity ethylene-oxide water feed streams to EO purification and MEG reaction units when both are operating in EO plants that incorporate EO Stripper bypass technology, by installing a second lights stripper to exclusively degasify the diluted EO feed to the MEG reactor, thus permitting the use of additional bypassed (gasified) EO absorbate as the diluent and resulting in a substantial increase in the total amount of EO absorbate that can bypass the EO Stripper.