Provided are a method and device for preparing adiponitrile. The method of the present disclosure comprises the steps of a first hydrocyanation reaction, an isomerization reaction and a second hydrocyanation reaction, wherein online Raman spectroscopy is used for detecting the content of a specific component in the system; and the reaction conditions are regulated based on the detection results, so as to achieve precise control of the materials in each step of the reaction system. The method of the present disclosure can reduce an amount of butadiene, thereby reducing the subsequent energy consumption needed for recycling butadiene and equipment investment after reaction; by monitoring the content of hydrocyanic acid in real time, the residue of hydrocyanic acid is reduced to a lower level, and the operation safety and the stability of a catalyst during reaction are improved; and the loss of the catalyst is reduced.

Provided is a method capable of yielding high-purity 1,3-butylene glycol having a very low content of a low boiling point component and a high initial boiling point, with a high recovery ratio. A reaction crude liquid containing 1,3-butylene glycol is subjected to product distillation to yield purified 1,3-butylene glycol, through dehydration including removing water by distillation and performing high boiling point component removal including removing a high boiling point component by distillation. A method for producing 1,3 butylene glycol, the method including: distilling a charged liquid having a water content of 1.2 wt.% or less in a product column for use in the product distillation under a condition of a reflux ratio of greater than 0.1; distilling off a liquid in which a low boiling point component is concentrated from above a charging plate; and extracting 1,3-butylene glycol from below the charging plate.

A semi-continuous deodorizer providing a first main vessel, and a second vessel, wherein the second vessel is connected to the first main vessel by a duct for the transport of gases and vapors, the second vessel being connected to a vacuum system, wherein both the first main vessel and the second vessel are made of stainless steel and built hermetically.

A system for producing ethanol comprises a rectifier column that receives a first process stream comprising from about 42% to about 60% ethanol, wherein the rectifier column purifies the first process stream to provide an ethanol product stream that is at least about 90% ethanol, and one or more evaporators configured to evaporate water from a second process stream, wherein the one or more evaporators generate vapor, and wherein at least a portion of the vapor supplies heat energy for separation of ethanol from water in the rectifier column.

This invention relates to a method of separating a multiproduct mixture using a prefractionation/main column arrangement to efficiently separate the multiproduct mixture into the desired individual products. One advantage of the invention is that it can be used to debottleneck an existing series of distillation columns, permitting a capacity expansion to take place without requiring the installation of an entire new train of distillation columns.

A method for preparing ethylene including: feeding a thermally cracked compressed stream to a first distillation apparatus selectively operating as a first deethanizer or a depropanizer; and feeding an overhead discharge stream of the first distillation apparatus to a second distillation apparatus. When the first distillation apparatus is operated as the first deethanizer, a bottom discharge stream of the second distillation apparatus is fed to a C2 separator. When the first distillation apparatus is operated as the depropanizer, the bottom discharge stream of the second distillation apparatus is passed through a third distillation apparatus and fed to the C2 separator.

1) A method for obtaining a concentrated protein-rich phase from residues of bioethanol production. 2.1) Previously, the separation of a protein-rich phase from whole stillage from bioethanol production has been achieved either by the addition of chemicals or by process steps that are complex in terms of equipment and/or energy. 2.2) Whole stillage from bioethanol production is fed to a solid-liquid separation, and the liquid phase (thin stillage) resulting from this is partially returned to the mashing process. This recirculation increases the raw protein content in the process. Part of the thin stillage is diluted and fed to a simple separation process without the addition of chemicals and temperature treatment, with a protein-rich phase being obtained. 2.3) A protein-rich phase is obtained from residues of bioethanol production.

A high-purity 1,3-butylene glycol product that is colorless and odorless (or almost colorless and odorless), unlikely to cause coloration and odor over time, and/or unlikely to cause an acid concentration increase over time when the product is left in a state containing water is provided. A 1,3-butylene glycol product containing 1,3-butylene glycol, wherein, after the 1,3-butylene glycol product has been kept at 180° C. for 3 hours in air atmosphere, at least one of contents of compounds represented by the following Formula (A) or (B) is less than 8 ppm. In the following formula, R.sup.1 to R.sup.4 are the same as or different from each other, and each of R.sup.1 to R.sup.4 is a hydrogen atom, an alkyl group which has from 1 to 4 carbon atoms and may be substituted with a hydroxy group, or an alkenyl group which has from 2 to 4 carbon atoms and may be substituted with a hydroxy group.

Methods and systems are provided for recovering an organic solvent from a waste sludge generated during formation of a polyarylene sulfide. Methods include combining the waste sludge with an anti-solvent to create a dispersion, which includes a solid phase that includes a substantial portion of the impurities of the polyarylene sulfide formation and a liquid phase that contains the anti-solvent and organic solvent employed during formation of the polyarylene sulfide. The liquid phase is separated from the solid phase and then subjected to a distillation process to separate the organic solvent from the anti-solvent. Methods can also include forming the polyarylene sulfide by a polymerization process and thereafter purifying a slurry of the polyarylene sulfide. A liquid washing product is formed as a result of the purification process, which can be subjected to a distillation process that forms an organic solvent-rich stream and the waste sludge.

The invention provides a process for regenerating a liquid absorbent, including: contacting the liquid absorbent with a hydrophobic medium, wherein the liquid absorbent includes at least one amine of Formula (I) ##STR00001##
and degradation product thereof including at least one imine of Formula (II), ##STR00002##
wherein each Ar is independently an aromatic group and each R is independently selected from hydrogen, an organyl group and NH2; and selectively extracting the degradation product into or through the hydrophobic medium.