Abstract: Processes have been developed for oxidizing alkyl aromatic compounds, and which reduce the amount of 4-CBA in the solid oxidation products. The process can reduce the makeup amount of ionic liquid, carboxylic acid, catalyst, bromine source, and ammonia source.

Abstract: Disclosed is a 5-alkyl-1,2,3,4-benzene tetracarboxylic-1:2,3:4-dianhydride which is represented by the general formula (1) and has excellent solubility with respect to various organic solvents. Depending on the diamine that is used, a polyimide with excellent heat resistance or a polyimide with good workability at a low melting point can be provided, and in addition, a polyimide that exhibits excellent characteristics for electronic materials or the like can be provided. (In the formula, R1 represents an alkyl group with carbon number 1-10.

Abstract: Methods of recycling a post-consumer polymer material comprise depolymerizing the polymer material by heating the polymer material in the presence of a hydrogen donor material and a strong base compound, and optionally a catalyst, to effect catalytic transfer hydrogenation and base cleavage and produce intermediate and/or monomer products of molecular weights lower than that of the polymeric material. In a specific embodiment, the methods comprise recycling post-consumer polyethylene terephthalate. The methods comprise depolymerizing the polyethylene terephthalate by heating in the presence of a hydrogen donor material and a strong base compound, and optionally a catalyst, to effect catalytic transfer hydrogenation and base cleavage and produce terephthalic and/or naphthalic acid, or a salt thereof, and ethylene glycol.

Abstract: Methods of making a modified pigment by reacting a first chemical group and a second chemical group to form a pigment having attached a third chemical group. The first chemical group includes at least one nucleophile and the second chemical group includes at least one electrophile, or vice versa. Resulting modified pigments, and ink compositions containing such pigments, are also described.

Abstract: There are provided a bottle which has a laminate structure including a glycolic acid polymer layer showing good gas-barrier property in addition to a principal resin layer and is yet provided with excellent recyclability, and also an efficient method of recycling the bottle. More specifically, a bottle having a laminate structure including at least one layer of glycolic acid polymer in addition to a principal resin layer, is obtained. After breaking the bottle, the broken pieces are washed with alkaline water, water or acidic water to remove the glycolic acid polymer layer, thereby recovering the principal resin.

Abstract: A method of decomposing a polycarbonate with water in a supercritical or subcritical state. A high-purity dihydroxy compound which is a constituent component of the polycarbonate can be recovered at a high yield by this decomposition method. This decomposition method is environment-friendly because it does not use an organic solvent, easy to be carried out, has a high decomposition rate and rarely causes a side reaction.

Abstract: A process for ethanolysis of PET is disclosed wherein a feed comprising PET is reacted with ethanol and recovering ethylene glycol and an aromatic diethyl ester such as diethyl isophthalate and/or diethyl terephthalate. PET, or a terpolymer comprising terephthalate monomer and ethylene glycol monomers, is reacted with ethanol and ethanol, diethyl terephthalate, ethylene glycol and optionally diethyl isophthalate are recovered. Recovered diethyl components can be subjected to liquid-phase oxidation to produce aromatic carboxylic acid. Acetic acid may also produced via liquid-phase oxidation of recovered diethyl components. The aromatic carboxylic acid can be used to form polymer.

Abstract: The present invention relates to a process of recovering aromatic dicarboxylic acids with low metal contaminants from manufactured articles, such as beverage bottles, fibers and films, comprising aromatic polyesters, whether or not those articles are contaminated with PVC or chlorinated compounds, or from waste from processing of these polyesters. In particular, the invention relates to the recovery of terephthalic acid, isophthalic acid and 2,6-naphthalene dicarboxylic acid from bottles for recycling which are made of PET, PEN or aromatic polyester copolymers.

Abstract: This invention provides a process a process for recovering terephthalic acid from pulverized products of spent polyethylene terephthalate.

Abstract: A process and a device for the catalytic hydrolysis of a carboxylate, e.g., methyl acetate, ethyl acetate, i- or n-propyl acetate, i- or n-butyl acetate, allyl acetate and methyl formate, into the corresponding carboxylic acid and alcohol, by a combination of a pre-reactor and a reactive distillation column are disclosed. By the combination of a pre-reactor and a reactor distillation column, the conversion ratio can be substantially improved. The device can compensate for fluctuations in the supply quantity or in the composition of the feed flow. The product composition can also be controlled in a wide range.

Abstract: The present invention relates to a method of recovering a solution comprising the chemical species obtained by depolymerization of PET from a material containing poly(ethylene terephthalate) in the form of bottles, by making said material react, in the absence of water, with a reagent consisting of one or more metal salts of a weaker acid than the terephthalic acid and of ethylene glycol, until a water-soluble intermediate product is obtained, and subsequently carrying out dissolution in water, stirring and filtering.

Abstract: The present invention relates to a method of recovering terephthalic acid from a material containing poly(ethylene terephthalate) (P.E.T.) in the form of bottles, by making said material react, in the absence of water, with a reagent consisting of one or more metal salts of a weaker acid than the terephthalic acid, until a water-soluble compound is obtained, and subsequently carrying out dissolution in water and acidification.

Abstract: This invention provides a process a process for recovering terephthalic acid from pulverized products of spent polyethylene terephthalate.

Abstract: The invention concerns a method for producing terephthalate of alkaline metal and alkylene glycol from recuperated alkylene polyterephthalate. It comprises saponification of said alkylene terephthalates with an aqueous sodium solution, adding a sufficient volume of water to ensure solubilization of the entire alkaline metal terephthalate produced in the reaction medium liquid phase and crystallisation of the sodium terephthalate by concentration of said liquid phase. The resulting sodium terephthalate can be directly used for producing pure terephthalic acid usable for the renewed production of alkylene polyterephthalates to be used in the food industry.

Abstract: The proposed method of chemical recycling of polyethylene terephthalate waste to terephthalic acid and ethandiol is based on a continuous series of gradual steps, namely (a) separation of the polyethylene terephthalate component of the input material by its conversion to brittle form through crystallization, grinding and subsequent sifting, followed by (b) continuous two-stage hydrolysis of the polyethylene terephthalate, carried out in the first stage by feeding steam to the polymer melt, and in the second stage, by the reaction of the products of the first stage of hydrolysis with ammonium hydroxide, followed by (c) condensation of terephthalic acid from an aqueous solution of the second-stage hydrolysis products by inorganic acid, and its separation by means of filtration, and finally (d) rectification separation of ethandiol from a solution of the products of the second stage of hydrolysis, after the separation of terephthalic acid.

Abstract: This invention provides a process a process for recovering terephthalic acid from pulverized products of spent polyethylene terephthalate.

Abstract: A method for the recovery of dicarboxylic aromatic acids, in particular terephthalic acid, from manufactured aromatic polyester-resin articles for recycling, wherein the article, fragmented into chip form, is reacted in solution in a carboxylic acid with 2-6 carbon atoms and with a pKa from 4 to 6, preferably glacial acetic acid, in the presence of catalytic quantities of a strong acid with a pKa of less than 1, preferably aqueous hydrochloric acid or sulfuric acid, operating at temperatures from 160° to 250° C.

Abstract: This invention relates in part to a processes for the conversion of a feedstock stream comprising carbon monoxide and hydrogen to a product stream comprising at least one of an ester, acid, acid anhydride and mixtures thereof. This invention also relates in part to processes for converting an alcohol and/or ether feedstock to oxygenated products, e.g., esters, acids, acid anhydrides and mixtures thereof. The processes and catalysts are especially suitable for the production of acetic acid and methyl acetate from a synthesis gas feedstock or from an alcohol and/or ether feedstock.

Abstract: The proposed method of chemical recycling of polyethylene terephthalate waste to terephthalic acid and ethandiol is based on a continuous series of gradual steps, namely (a) separation of the polyethylene terephthalate component of the input material by its conversion to brittle form through crystallization, grinding and subsequent sifting, followed by (b) continuous two-stage hydrolysis of the polyethylene terephthalate, carried out in the first stage by feeding steam to the polymer melt, and in the second stage, by the reaction of the products of the first stage of hydrolysis with ammonium hydroxide, followed by (c) condensation of terephthalic acid from an aqueous solution of the second-stage hydrolysis products by inorganic acid, and its separation by means of filtration, and finally (d) rectification separation of ethandiol from a solution of the products of the second stage of hydrolysis, after the separation of terephthalic acid.

Abstract: A process for producing high quality TPA suitable for PET feedstock material from recycled polyester. The process includes the steps of depolymerizing the polyester to form DMT; separating the DMT from secondary materials; and hydrolyzing the DMT to form TPA. In a preferred embodiment of the invention the recycled polyester is contacted with a component monomer or oligomer thereof to liquefy the polyester prior to depolymerizing the polyester.

Abstract: Processes for producing aromatic monomers useful for forming polyesters are disclosed. Cost effective steps employed in the processes permit small amounts of process-related materials typically removed from monomer to remain in an aromatic monomer product. In many cases, the presence of the process-related materials left in the monomer product by the cost effective process steps can enhance the performance of the monomer in certain applications.

Abstract: A method of decomposing wastes containing target compounds having one or more of hydrolyzable bonds of ether bond, ester bond, amide bond and isocyanate bond wherein the method comprises continuously supplying the wastes in a molten state or liquid state to a reactor, continuously supplying super-critical water or high pressure/high temperature water to the reactor, bringing the water into contact with the wastes, thereby decomposing the target compounds and then recovering them as raw material compounds or derivatives thereof for the target compounds. Target compounds contained in wastes in chemical plants which could not be utilized but merely incinerated or discarded so far are continuously decomposed into raw material compounds or derivatives thereof for the aimed compound and can be reutilized effectively.

Abstract: A process for producing 2,3,5,6-tetrachloro-1, 4-benzenedicarboxylic acid, comprising heating 2,3,5,6-tetrachloro-1,4-benzenedicarboxamide together with sulfuric acid exhibiting an acidity function (—Ho) of 10.27 to 14.44 in the presence of water contained in an amount smaller than a stoichiometric value of hydrolysis at 110 to 190° C. This process efficiently produces 2,3,5,6-tetrachloro-1,4-benzenedicarboxylic acid which is a precursor of dimethyl 2,3,5,6-tetrachloro-1,4-benzenedicarboxylate useful as a herbicide.

Abstract: A method for the recovery of dicarboxylic aromatic acids, in particular terephthalic acid, from manufactured aromatic polyester-resin articles for recycling, wherein the article, fragmented into chip form, is reacted in solution in a carboxylic acid with 2-6 carbon atoms and with a pKa from 4 to 6, preferably glacial acetic acid, in the presence of catalytic quantities of a strong acid with a pKa of less than 1, preferably aqueous hydrochloric acid or sulphuric acid, operating at temperatures from 160° to 250° C.

Abstract: The present invention relates to a method of recovering a solution comprising the chemical species obtained by depolymerization of PET from a material containing poly(ethylene terephthalate) in the form of bottles, by making said material react, in the absence of water, with a reagent consisting of one or more metal salts of a weaker acid than the terephthalic acid and of ethylene glycol, until a water-soluble intermediate product is obtained, and subsequently carrying out dissolution in water, stirring and filtering.

Abstract: A process for producing 2,3,5,6-tetrachloro-1,4-benzenedicarboxylic acid, comprising heating 2,3,5,6-tetrachloro-1,4-benzenedicarboxamide together with sulfuric acid exhibiting an acidity function (—Ho) of 10.27 to 14.44 in the presence of water contained in an amount smaller than a stoichiometric value of hydrolysis at 110 to 190° C. This process efficiently produces 2,3,5,6-tetrachloro-1,4-benzenedicarboxylic acid which is a precursor of dimethyl 2,3,5,6-tetrachloro-1,4-benzenedicarboxylate useful as a herbicide.

Abstract: Processes for producing aromatic monomers useful for forming polyesters are disclosed. Cost effective steps employed in the processes permit small amounts of process-related materials typically removed from monomer to remain in an aromatic monomer product. In many cases, the presence of the process-related materials left in the monomer product by the cost effective process steps can enhance the performance of the monomer in certain applications. Aromatic monomer products and polymers produced therefrom having these advantages also are disclosed, as well as products such as pasteurizable bottles made from these polymers.

Abstract: A method of decomposing wastes containing target compounds having one or more of hydrolyzable bonds of ether bond, ester bond, amide bond and isocyanate bond wherein the method comprises continuously supplying the wastes in a molten state or liquid state to a reactor, continuously supplying super-critical water or high pressure/high temperature water to the reactor, bringing the water into contact with the wastes, thereby decomposing the target compounds and then recovering them as raw material compounds or derivatives thereof for the target compounds. Target compounds contained in wastes in chemical plants which could not be utilized but merely incinerated or discarded so far are continuously decomposed into raw material compounds or derivatives thereof for the aimed compound and can be reutilized effectively.

Abstract: A process for preparing an aromatic carboxylic acid having improved purity comprising contacting at an elevated temperature and pressure a mixture comprising an impure aromatic carboxylic acid and a solvent in the presence of hydrogen gas with a carbon catalyst which is essentially free of a hydrogenation metal component.

Abstract: A process for preparation of crosslinked cellulosic products containing at least 30 wt. % cellulosic fibers and the polyanhydride crosslinked cellulosic products resulting therefrom wherein a cellulosic material is treated with an aqueous solution of a polycarboxylic acid formed by hydrolysis of a polyanhydride of the structure which comprises the reaction product of trimellitic anhydride and a diol in the mole ratio of from about 2.0:0.9 to about 2.0:1.1, wherein R is selected from the group consisting of alkyl, alkylene and cycloalkylene moieties of up to 12 carbon atoms and ethylene oxide and propylene oxide moieties of molecular weight up to about 6000, wherein said cellulosic material is impregnated with an aqueous solution of said polyanhydride, dried, and heated to a temperature of from about 120° C. to about 200° C.

Abstract: A subject of the invention is the method of recovery of terephthalic acid and ethylene glycol from poly/ethylene terephthalate/wastes. According to the invention poly/ethylene terephthalate/ is heated in an aqueous solution at the temperature from 150° C. to 280° C. with a reagent substance, chosen from the group, comprising bicarbonates of ammonia and alkali metals, ammonium carbamate and urea, which substances are used in amounts not less than a stoechiometric amount.

Abstract: This invention concerns a method for recycling polyesters comprising the hydrolysis of polyesters containing repeat units derived from 2,6-naphthalene dicarboxylic acid in the presence of a carboxylic acid which gives pure 2,6-naphthalene dicarboxylic acid suitable for use as a monomer.

Abstract: This invention relates to a process for manufacturing terephthalic acid and more particularly, to a process for manufacturing terephthalic acid in a high recovery rate with high purity in accordance with the practice of this invention comprising the following procedures: polyethylene terephthalate (hereinafter referred to as "PET") scrap is hydrolyzed with alkaline aqueous solution to give the slurry of terephthalic acid alkali metal/earth metal salt, then the particles of terephthalic acid formed from acid-neutralization are enlarged to recover terephthalic acid with high purity.

Abstract: This invention relates to a process for manufacturing terephthalic acid and more particularly, to a process of manufacturing and recovering the highly purified terephthalic acid using an alkali weight-reduction waste water discharged from weight-reduction process in a polyester textile dyeing complex, in accordance with the practice of this invention comprising the following procedures: polyethylene terephthalate (hereinafter referred to "PET") waste scrap materials are hydrolyzed to prepare the slurry of disodium terephthalate. Then, said slurry dissolved in water is adsorbed to remove impurities, and followed by acid-neutralization to obtain terephthalic acid of this invention.

Abstract: A method and apparatus for purifying crude terephthalic acid from a liquid dispersion thereof also containing impurities selected from unreacted starting materials, solvents, products of side reactions and/or other undesired materials is provided. The method comprises the steps of filtering the dispersion to form a crude terephthalic acid filter cake, dissolving the filter cake in a selective crystallization solvent at an elevated temperature to form a solution, crystallizing purified terephthalic acid from the solution in the crystallization solvent by reducing the pressure and temperature of the solution, and separating the crystallized purified terephthalic acid from the solution. According to the invention, the selective crystallization solvent is non-aqueous, non-corrosive and essentially non-reactive with terephthalic acid. Preferably, the selective crystallization solvent is N-methyl pyrrolidone.

Abstract: A process for preparation of crosslinked cellulosic products containing at least 30 wt. % cellulosic fibers and the polyanhydride crosslinked cellulosic products resulting therefrom wherein a cellulosic material is treated with an aqueous solution of a polycarboxylic acid formed by hydrolysis of a polyanhydride of the structure ##STR1## which comprises the reaction product of trimellitic anhydride and a diol in the mole ratio of from about 2.0:0.9 to about 2.0:1.1, wherein R is selected from the group consisting of alkyl, alkylene and cycloalkylene moieties of up to 12 carbon atoms and ethylene oxide and propylene oxide moieties of molecular weight up to about 6000, wherein said cellulosic material is impregnated with an aqueous solution of said polyanhydride, dried, and heated to a temperature of from about 120.degree. C. to about 200.degree. C.

Abstract: Alkyl- and arylmalonic acids of the formula I ##STR1## where R.sup.1 =H, C.sub.1 -C.sub.12 -alkyl, phenyl, C.sub.1 -C.sub.4 -alkylphenyl, C.sub.2 -C.sub.4 -dialkylphenyl,R.sup.2 =C.sub.1 -C.sub.12 -alkyl, phenyl, C.sub.1 -C.sub.4 -alkylphenyl, C.sub.2 -C.sub.4 -dialkylphenyl orR.sup.1 +R.sup.2 =--CH.sub.2 --CH.sub.2 --, are prepared by alkaline saponification by hydrolyzing the corresponding C.sub.1 -C.sub.4 -alkyl esters of the malonic acid of formula I, with alkali metal hydroxide dissolved in an aqueous alkali metal salt solution containing salt at 90-100% of saturation, acidifying the hydrolysis product with a mineral acid, removing the precipitated alkali metal salt which forms upon acidification, and extracting the alkyl- and arylmalonic acid formed from the aqueous solution with the aid of an organic solvent.

Abstract: A method and apparatus for purifying crude terephthalic acid from a liquid dispersion thereof also containing impurities selected from unreacted starting materials, solvents, products of side reactions and/or other undesired materials is provided. The method comprises the steps of filtering the dispersion to form a crude terephthalic acid filter cake, dissolving the filter cake in a selective crystallization solvent at an elevated temperature to form a solution, crystallizing purified terephthalic acid from the solution in the crystallization solvent by reducing the temperature of the solution, and separating the crystallized purified terephthalic acid from the solution. According to the invention, the selective crystallization solvent is non-aqueous, non-corrosive and essentially non-reactive with terephthalic acid. Preferably, the selective crystallization solvent is N-methyl pyrrolidone.

Abstract: Dicarboxylic acids or esters thereof are recovered from solid phase polyester materials, such as post-consumer products and factory scrap, by initially subjecting the polyester to a glycolysis reaction (in one or more stages) to produce a liquid phase medium containing depolymerisation products. The liquid phase medium is then contacted with aqueous medium or alcohol in one or ore stages to produce the dicarboxylic acid or an ester thereof together with glycol.

Abstract: The invention relates to a process for removing amino acids and/or aminosulphonic acids from preferably aqueous solutions which contain these as impurities by adsorbing the amino acids on zeolites. Solutions to which the process according to the invention can be applied are produced, for example, from the industrial synthesis of oligopeptides in which the amino acids serving as starting materials are always present in solution, sometimes to a not inconsiderable residual concentration, together with the desired end product.

Abstract: A process for preparing purified 2,6-naphthalenedicarboxylic acid which comprises hydrolyzing a dialkyl-2,6-naphthalenedicarboxylate with water at a reaction temperature of at least about 450.degree. F. under liquid phase condition, the amount of water present being sufficient to solubilize, at the reaction temperature, at least about 10 percent of the 2,6-naphthalenedicarboxylic acid formed; and a process for purifying 2,6-naphthalenedicarboxylic acid comprising combining impure 2,6-naphthalenedicarboxylic acid with a purification solvent, heating the resulting mixture under liquid phase conditions at a temperature of at least about 500.degree. F. to form a product mixture and thereafter recovering from the product mixture purified 2,6-naphthalenedicarboxylic acid.

Abstract: The present invention relates to a process for the preparation of salts of substituted or unsubstituted phthalic acids, by reacting a compound of the formula ##STR1## in which R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are identical or different and are H, F, Cl, Br, CF.sub.3, OH, an alkoxy or alkyl radical in each case having 1 to 4 carbon atoms, or a radical --NR.sup.7 R.sup.8, in which R.sup.7 and R.sup.8 are identical or different and are H, an alkyl radical having 1 to 4 carbon atoms, or a phenyl radical, R.sup.5 and R.sup.6 are identical or different and are H, a --CO-- alkyl group having 1 to 6 carbon atoms in the alkyl radical, or a benzoyl group, or R.sup.5 and R.sup.6 together form a radical of the formula ##STR2## in which R.sup.9, R.sup.10, R.sup.11 and R.sup.12 are identical or different and are H, F, Cl, Br, CF.sub.3, OH, an alkoxy or alkyl radical in each case having 1 to 4 carbon atoms, or a radical --NR.sup.7 R.sup.8, in which R.sup.7 and R.sup.

Abstract: A process for the preparation of terephthalic acid (TA) from pure dimethyl terephthalate (DMT) and/or DMT intermediate product by hydrolysis in a countercurrent reactor at a conversion of greater than 99% and crystallization to give the solid product, characterized in that the sum of the stripping steam (S) and reaction water (W) satisfies the relationshipL.ltoreq.S+W.ltoreq.2L,wherein (L) represents the amount of water necessary to keep the terephthalic acid (TA) produced largely in solution during the reaction and in the bottom of the reactor, and the terephthalic acid produced is crystallized in a crystallization which is free from washing stages.

Abstract: A process for the transesterification of dimethyl succinylsuccinate with one or more aliphatic alcohols which in each case have at least 2 C atoms, in the presence of an acidic catalyst and in the presence or absence of a diluent which is inert under the reaction conditions, with exclusion of oxygen and under pressure, at least one of the two methoxy groups being replaced by the oxy group corresponding to the alcohol used and use of the process in a process for the preparation of terephthalic acids and of quinacridones.

Abstract: There is described a process for the depolymerization of polyethylene terephthalate into component monomers at ambient pressure. Monomer solids that deposit during cooling, as part of the recovery operation, are removed using a scraped wall heat exchanger.

Abstract: A process for preparing purified 2,6-naphthalenedicarboxylic acid which comprises hydrolyzing a dialkyl-2,6-naphthalenedicarboxylate with water at a reaction temperature of at least about 450.degree. F. under liquid phase condition, the amount of water present being sufficient to solubilize, at the reaction temperature, at least about 10 percent of the 2,6-naphthalenedicarboxylic acid formed; and a process for purifying 2,6-naphthalenedicarboxylic acid comprising combining impure 2,6-naphthalenedicarboxylic acid with a purification solvent, heating the resulting mixture under liquid phase conditions at a temperature of at least about 500.degree. F. to form a product mixture and thereafter recovering from the product mixture purified 2,6-naphthalenedicarboxylic acid.

Abstract: 3,4,6-trifluorophthalic acid is prepared in high yield by reaction of a 3,4,6-trichloro-N-substituted phthalimide with potassium fluoride at temperatures in the range of 200.degree. to 270.degree. C. in the absence of a catalyst to form the corresponding trifluoro-N-substituted phthalimide which, in turn, is hydrolyzed to form the 3,4,6-trifluorophthalic acid.

Abstract: Fluorinated carboxylic acids can be recovered from materials which contain them by releasing, if necessary, the carboxylic acids with sufficiently strong acids, esterifying the released acids and distilling off the esters. The esters can be advantageously directly hydrolyzed with aqueous ammonia solution to give the corresponding ammonium salts.

Abstract: There is described a process for the depolymerization of polyethylene terephthalate into component monomers using a reactor in which the polyethylene terephthalate is a discontinuous phase which contacts a continuous phase of superheated methanol vapor.

Abstract: A process for preparing purified 2,6-naphthalenedicarboxylic acid which comprises hydrolyzing a dialkyl-2,6-naphthalenedicarboxylate with water at a reaction temperature of at least about 450.degree. F. under liquid phase condition, the amount of water present being sufficient to solubilize, at the reaction temperature, at least about 10 percent of the 2,6-naphthalenedicarboxylic acid formed; and a process for purifying 2,6-naphthalenedicarboxylic acid comprising combining impure 2,6-naphthalenedicarboxylic acid with a purification solvent, heating the resulting mixture under liquid phase conditions at a temperature of at least about 500.degree. F. to form a product mixture and thereafter recovering from the product mixture purified 2,6-naphthalenedicarboxylic acid.