The present invention provides a process for the production of an aromatic dicarboxylic acid comprising the catalytic oxidation of a hydrocarbon precursor in an organic solvent, comprising the steps of: i) separating a vent gas from an oxidation stage into an organic solvent-rich liquid stream and a water-rich vapour stream in a distillation stage; and ii) separating an aqueous purific ation mother liquor comprising organic compounds from purified aromatic dicarboxylic acid crystals in a separation stage, characterised in that the process further comprises the steps of: iii) transferring the aqueous purification mother liquor from the separation stage to an extraction stage; iv) extracting said organic compounds from the aqueous purification mother liquor by contacting the aqueous purification mother liquor at a temperature of at least 90° C. with an organic liquid in the extraction stage to form an aqueous phase and an organic phase, wherein the concentration of said organic compounds in the aqueous phase is lower than the concentra tion of said organic compounds in the aqueous purification mother liquor; and v) transferring the aqueous phase to said distillation stage. The present invention further provides an apparatus for carrying out the process.

The present subject matter relates to methods and apparatuses for the continuous preparation of a cumene feed for a cumene oxidation process. More specifically, the subject matter relates to a process for passing a cumene alpha-methylstyrene stream through a caustic wash column having an integrated water wash section for the removal of organic acids.

The invention concerns a method for purifying a hydroalcoholic feedstock, comprising: a) a step of counter-current liquid-liquid extraction, comprising an extraction section supplied at the top with said hydroalcoholic feedstock and at least one intermediate raffinate fraction from step b) and at the bottom with an extraction solvent, and producing at the top an extraction stream and at the bottom a raffinate, wherein the extraction section is operated at a mean temperature in the extractor of between 10 and 40° C.; b) a counter-current liquid-liquid back-extraction comprising a back-extraction section supplied at the top with an acidic aqueous solution, having a pH between 0.5 and 5.0, and at the bottom with the extraction stream from step a), and producing at the top an extract and at the bottom the intermediate raffinate, wherein the back-extraction section is operated at a mean temperature between 40 and 80° C.

Disclosed is a method for treating water, including the extraction of at least two ionic species, the ionic species including an anionic species and a cationic species and being present in the water to be treated, the method especially including a step of mixing a liquid hydrophobic organic phase and the water to be treated, the water to be treated being in the liquid state, in order to subsequently obtain liquid treated water and a hydrophobic liquid organic phase loaded with the ionic species, and a step of thermal regeneration of the organic phase loaded with chemical species. Also disclosed are compounds and compositions that can be used in the method.

The present disclosure relates to a composition that includes a lignin-derived mixture that includes at least one of a dimer, a trimer, and/or a tetramer, where the composition is characterized by a thermal stability up to a maximum temperature between about 260° C. and about 300° C.

Disclosed is a method for treating water, including the extraction of at least two ionic species, the ionic species including an anionic species and a cationic species and being present in the water to be treated, the method especially including a step of mixing a liquid hydrophobic organic phase and the water to be treated, the water to be treated being in the liquid state, in order to subsequently obtain liquid treated water and a hydrophobic liquid organic phase loaded with the ionic species, and a step of thermal regeneration of the organic phase loaded with chemical species. Also disclosed are compounds and compositions that can be used in the method.

A method of extracting propionitrile from liquid chloropicrin includes providing a feed solution that constitutes liquid chloropicrin and a propionitrile solute dissolved therein. A liquid, water-based solvent that is immiscible with the feed solution is also provided. The feed solution and the solvent are intermixed such that the solvent absorbs and extracts at least a portion of the propionitrile solute from the feed solution. The feed solution is then separated from the solvent and extracted propionitrile solute to produce a liquid extract and a liquid raffinate, which liquid extract includes the water-based solvent and the propionitrile solute absorbed by the solvent, and which raffinate includes the feed solution from which propionitrile solute has-been extracted.

The methods described herein produce a naphthenic process oil, as classified by ASTM D-2226, containing 35-65% saturates and 35-65% aromatics as determined by ASTM D-2007. The produced naphthenic process oil also contains polyaromatic hydrocarbons (PAH), more specifically the EU/US EPA 8-regulated PAHs, less than 10 ppm. The naphthenic process oil is produced by first feeding gas oil ranging in viscosities up to 20 cSt at 100° C. through counter-current liquid-liquid extraction towers with a solvent having a selective affinity for aromatics. The extract is then cooled and either continuously processed through a coalescing separator or batch processed in a tank or decanter to produce a second raffinate, which can be further distilled to produce the naphthenic process oil.

A method for manufacturing carboxylic acid that includes the following steps is provided. First, subjecting an aqueous mixture, including carboxylic acid and at least 5 wt. % dissolved magnesium chloride, to a forward extraction step using a first organic liquid, including an organic solvent, the organic solvent being selected from the group of C5+ ketones, thereby obtaining an organic carboxylic acid solution and an aqueous waste liquid including magnesium chloride. Second, subjecting the organic carboxylic acid solution to a back extraction step wherein the carboxylic acid is extracted from the organic carboxylic acid solution into an aqueous liquid, thereby obtaining an aqueous carboxylic acid solution and a second organic liquid. Third, subjecting the aqueous waste liquid including magnesium chloride derived from the forward extraction to a thermal decomposition step at a temperature of at least 300° C., thereby decomposing the magnesium chloride to magnesium oxide and HCl.

Disclosed are a pretreatment method and system for a fraction oil for the production of alkylbenzene, the method comprising: adding a fraction oil, a weak base solution and an inorganic salt solution into a reactor, and leaving same to stand and layering same after the reaction is complete; adding water and an inorganic salt solution into an oil phase for washing with water; extracting same with a polar solvent having a high boiling point, and then adsorbing same with an adsorbent to separate oxygen-containing compounds in the neutral fraction oil; sending the extraction agent containing the oxygen-containing compounds to an extraction agent recovery unit; and then sending the neutral fraction oil to an alkylation reactor for a reaction.