Abstract: An improved method for recovery of alkali metal or alkaline-earth metal terephthalate and of alkylene glycol, from polyalkylene terephthalate, in particular from polyethylene terephthalate (P.E.T.), alkylene glycol, in particular ethylene glycol produced in the form of vapor during the saponification reaction, initiated by the action of intensive kneading of polyalkylene terephthalate and the alkaline reagent at a temperature of 100.degree. to 200.degree. C. The alkylene glycol is recovered in gaseous form by entrainment by an inert gas or by extraction under low pressure. The alkaline terephthalate or alkaline-earth terephthalate is obtained in solid or powder form; it can easily be stored, transported and redissolved, in order to be purified and possibly transformed into terephthalic acid or ester.

Abstract: A process for producing tetrafluorophthalic anhydride, which comprises chlorinating tetrachlorophthalic anhydride to obtain 3,3,4,5,6,7-hexachloro-1-[3H]-isobenzofuranone, then fluorinating it to obtain 3,4,5,6-tetrafluorophthaloyldifluoride and/or 3,3,4,5,6,7-hexafluoro-1-[3H]-isobenzofuranone, and further reacting the tetrafluorophthalolyldifluoride and/or the hexafluoro-1-[3H]-isobenzofuranone with an inorganic base or an organic acid to obtain tetrafluorophthalic anhydride.

Abstract: A process for the continuous hydrolysis of esters containing from 2 to about 16 carbon atoms to form at least one alcohol and at least one carboxylic acid and the concurrent separation of the hydrolysis products has been developed. The process uses a solid bed which acts as a catalyst for hydrolysis and as an adsorbent for at least one class of the products. The process operates in the simulated moving bed mode. A specific embodiment of the invention is one where the simulated moving bed is a homogeneous mixture of at least one solid effective as a hydrolysis catalyst and at least one solid effective as an alcohol or carboxylic acid adsorbent. Another specific embodiment is one where the simulated moving bed is a strongly acidic macroreticular polymeric resin effective both as a hydrolysis catalyst and as an adsorbent for at least one hydrolysis product.

Abstract: Processes are disclosed for recovery and purification of dibasic aromatic acids from waste polyester film, fiber, bottles, manufacturing residues, and other manufactured articles. The processes comprises: depolymerization of polyester resin in a molten polyester resin containing solvent with superheated stem, and vaporization of the aromatic carboxylic acid and other volatile products of hydrolysis to obtain a vaporized mixture containing aromatic acid, dihydric alcohol, other volatile products of hydrolysis, and water. This vapor mixture is, advantageously, substantially free of less volatile and non-volatile impurities including metals, and many colored and color causing compounds, which are, typically, found in post-consumer polyester resins.

Abstract: A process for recovering monomer from multi-component waste material that includes a hydrolyzable polymer, the process including contacting the multi-component waste material with water and subjecting the resulting mixture to heat and pressure to form a liquid aqueous portion which mainly includes depolymerization products of the hydrolyzable polymer and a water insoluble portion which mainly includes components other than the depolymerization products; separating the liquid aqueous portion and the water insoluble portion; subjecting the separated aqueous portion to a pressure that is lower than that of step (a) and heat to produce a residue and a distillate which contains monomer; and separating the monomer in the distillate from other components in the distillate. The process is particularly useful for recovering caprolactam from waste materials that include nylon 6.

Abstract: Caprolactam is obtained from mixtures which contain polymers or thermoplastic molding materials having the repeating unit--N(H)--(CH.sub.2).sub.5 --C(O)--(a) by cleavage at elevated temperatures in the presence of a base under reduced pressure or (b) in the presence of water, by using a mixture essentially comprisingfrom 50 to 99.9% by weight of a polymer or of a thermoplastic molding material having the repeating unit--N(H)--(CH.sub.2).sub.5 --C(O)--from 0.1 to 50% by weight of additives selected from the group consisting of inorganic fillers, organic and inorganic pigments and dyes,from 0 to 10% by weight of organic and/or inorganic additives,from 0 to 40% by weight of non-polyamide-containing polymers andfrom 0 to 20% by weight of polyamides, with the exception of polycaprolactam and copolyamides prepared from caprolactam,and carrying out the cleavage in the presence of a base under reduced pressure, the water content of the mixture used being not more than 0.

Abstract: A process for the production of terephthalic acid comprises subjecting polyalkylene terephthalate to hydrolysis using a ratio of water to polyalkylene terephthalate in the mixture prior to heating and carrying out the reaction under conditions such that, at the reaction temperature, a significant proportion of the terephthalic acid produced is in the solid phase. The degree of recrystallization necessary to recover the terephthalic acid produced is thereby reduced. The reaction can with advantage be carried out with alkylene glycol present in the mixture prior to hydrolysis.

Abstract: Processes are disclosed for recovery and purification of dibasic aromatic acids from waste polyester film, fiber, bottles, manufacturing residues, and other manufactured articles. The processes comprises: depolymerizing polyester resin in a solvent under conditions suitable for hydrolysis of ester bonds to obtain a mixture containing a solution of aromatic acid and impurities consisting of alcohol and/or other components of the resin; burning impurities in a liquid-phase oxidation with an oxygen-containing gas in the presence of an oxidation catalyst at elevated pressures and temperatures, to obtain an oxidation product containing the desired aromatic acid; and crystallizing and separating from the oxidation system a resulting crude dibasic aromatic acid.

Abstract: Disclosed are novel compounds having the formula ##STR1## where A is O or NR, each R' independently selected from hydrogen, R, or M, R is alkyl, aryl, alkaryl, or aralkyl from C.sub.1 to C.sub.12, and M is a cation. Also disclosed is a method of making those compounds and a method of making a mixture of 3,5-difluorobenzoic acid and 1,3-difluorobenzene by reacting 3,5-dichlorophthalic anhydride with a fluorinating agent to produce 3,5-difluorophthalic anhydride, reacting the 3,5-difluorophthalic anhydride with water to produce 3,5-difluorophthalic acid, and decarboxylating the 3,5-difluorophthalic acid.

Abstract: The present invention relates to a process for the preparation of tetrafluorophthalic acid and/or tetrafluorophthalic anhydride by reacting a compound of the formula ##STR1## in which X is a radical ##STR2## which is optionally mono- or polysubstituted on the aromatic nucleus by fluorine and/or chlorine and/or alkyl groups having 1 to 4 carbon atoms, or is a radical ##STR3## in which R.sub.1, R.sub.2 and R.sub.3 are as defined, with water, and subsequently removing the water still present by azeotropic distillation or extracting the tetrafluorophthalic acid and/or its anhydride with a water-insoluble solvent or solvent mixture.

Abstract: The invention relates to a process for the production of a DMT intermediate product as well as its working up to fibregrade DMT and to medium pure and pure terephthalic acid.

Abstract: Ester bonds are hydrolyzed in the conversion of substantially amorphous polyesters to their monomeric components, by being contacted with a mixture of (a) an alcohol, such as methanol, or glycol, (b) a polar aprotic solvent such as N-methyl-pyrrolidone or dimethyl sulfoxide and (c) an alkoxide or hydroxide such as sodium hydroxide.

Abstract: A process for the selective hydrodefluorination of a tetrafluorophthalimide compound of the formula ##STR1## where X is 1 and R is a monovalent organo group; or X is 2 and R is a divalent organo group; comprises reacting (I) the tetrafluorophthalimide with zinc in an aqueous alkali metal hydroxide medium. The product may be hydrolyzed to form 3,4,6-trifluorophthalic acid.

Abstract: The invention relates to a process for the production of a DMT intermediate product as well as its working up to fibregrade DMT and to medium pure and pure terephthalic acid.

Abstract: A high purity naphthalene dicarboxylic acid (NDCA) is easily and rapidly produced by reacting a dialkylester of NDCA within a temperature range of 70.degree.-350.degree. C.

Abstract: An improvement in the oxidation catalyst used for the partial oxidation of n-butane and containing vanadium and phosphorus, zinc and lithium mixed oxides which comprises adding a molybdenum compound modifier in an amount of from about 0.005 to 0.025/1 Mo/V to the catalyst during the digestion of the reduced vanadium compound by concentrated phosphoric acid. The addition of Mo produces a catalyst which is very stable more active system and longer lived than the unmodified catalyst.

Abstract: A 3,4,3',4'-substituted biphenyl compound represented by the general formula (II): ##STR1## wherein, one of R.sup.1 and R.sup.2 is a -CH.sub.3 group and the one other is a --COOR.sup.5 group, --COOH group, or --COCl group, and one of R.sup.3 and R.sup.4 is a -CH.sub.3 group and the other one is a --COOR.sup.5 group, --COOH group, or --COCl group, is produced by the steps of oxidatively coupling an o-toluic acid alkyl ester in the presence of a catalyst containing a mixture of palladium salts with 1,10-phenanthroline or .alpha.,.alpha.'-bipyridine, a chelating product of a palladium salt with 1,10-phenanthroline, or a chelating products of a palladium salt with .alpha.,.alpha.

Abstract: Process for the preparation of 3,4,6-tetrafluorophthalic acid of the formula (1) ##STR1## or the anhydride thereof in good yields and in an advantageous manner, by dehalogenating tetrafluorophthalic anhydride of the formula (2) ##STR2## or tetrafluorophthalic acid in aqueous-alkaline medium using zinc at temperatures of approximately 20.degree. C. to approximately 160.degree. C. and, if appropriate, converting the resulting 3,4,6-trifluorophthalic acid into the anhydride in a known manner by dehydrating it.

Abstract: A process is disclosed for producing fiber-grade terephthalic acid from waste polyethylene terephthalate film, fiber, bottles, manufacturing residues, and other manufactured articles. The process comprises depolymerizing waste polyethylene terephthalate in an aqueous mixture to obtain crude terephthalic acid having a b*-value less than 10.00 and an RFCVIS value of about 5000, or greater, which is thereupon hydrogenated in aqueous solution for a period of up to 8 hours. Organic and inorganic impurities are retained in the aqueous components. The purified terephthalic acid has a b*-value less than 2.00, a relative fluorescence concentration in visible light (RFCVIS) of less than 2500, metals content less than 100 ppmw and total organic impurities of less than 1000 ppmw.

Abstract: A catalyst composition comprising a perfluorinated ion-exchange polymer containing sulfonic acid groups supported on an inert carrier having a hydrophobic surface with a mean pore diameter of at least 1000 .ANG.. Use of this catalyst provides improved hydrocarbon conversion processes for oligomerization of olefins, hydration of olefins and hydrolysis of esters.

Abstract: A process for dimerizing an aromatic halogen compound is disclosed, which comprises the step of: subjecting an aromatic halogen compound having at least one halogen atom bonded to an aromatic nucleus carbon to a dehalogenation-dimerization reaction in the presence of a catalyst, water, a reducing agent, and a halogen acceptor, the catalyst comprising a carrier supported thereon palladium and iron.

Abstract: Plychlorophthalimides, specifically, N-substituted tetrachlorophthalimides and N-substituted trichlorophthalimides may be treated with zinc and a base in aqueous soluction to yield, after acidification, the product 3,5-dichlorophthalic acid or salts thereof.

Abstract: A process for producing highly pure 2,6-napthalene dicarboxylic acid, characterized by hydrolyzing 2,6-dimethyl naphthalene dicarboxylate more than 99% pure in an aqueous solution by using an aromatic poly-carboxylic acid as a catalyst is disclosed.

Abstract: A method of recovering ethylene glycol and dimethyl terephthalate from scrap polyethylene terephthalate resins by dissolving the scrap in oligomers of the same monomers and passing methanol through the solution.

Abstract: Highly pure 3,3',4,4'-biphenyltetracarboxylic acid (BPTA) and dianhydride thereof (BPDA) are produced by heating crude BPTA to give BPDA, treating the BPDA with hot water to give highly pure BPTA, and in the case of highly pure BPDA, heat treating the pure BPTA to give highly pure BPDA.

Abstract: Ester bonds are hydrolyzed, such as in the conversion of polyesters to their monomeric components, by being contacted with a mixture of (a) an alcohol, such as methanol, or glycol, (b) a polar aprotic solvent such as N-methyl-pyrrolidone or dimethyl sulfoxide and (c) an alkoxide or hydroxide such as sodium hydroxide.

Abstract: A method of manufacturing an alkali metal salt of 2,3,6,7-naphthalenetetracarboxylic acid. Either a sodium salt or a mixture of sodium salt and potassium salt of at least one naphthalenecarboxylic acid selected form the group consisting of naphthoic acids and naphthalenepolycarboxylic acids is heated to an elevated temperature in an inert gas atmosphere in the presence of a Henkel reaction catalyst and halogenated sodium.

Abstract: A process for producing tetrafluorophthalic acid is disclosed, which comprises the steps of:(a) reacting an alkali metal fluoride and at least one imide compound represented by formula (I) or (II) ##STR1## wherein X.sup.1, X.sup.2, X.sup.3, and X.sup.4, which may be the same or different, each represents a chloride atom or a bromine atom, R.sup.1 represents a monovalent organic group, and R.sup.2 represents a divalent organic group, to provide an N-substituted tetrafluorophthalimide; and(b) hydrolyzing the tetrafluorophthalimide in the presence of an acid.

Abstract: A process for the production of terephthalic acid from p-xylene and methanol by way of the dimethyl terephthalate obtained by oxidation, in the liquid phase with atmospheric oxygen in the presence of dissolved heavy metal compounds as the catalyst, of a mixture of p-xylene and a fraction containing predominantly methyl p-toluate, which fraction is recycled into the oxidation, to obtain an oxidation product containing primarily p-toluic acid and monomethyl terephthalate at a temperature of 140.degree.-170.degree. C. and under a pressure of 4-8 bar; by esterification of the oxidation product in a reactor with liquid and subsequently vaporized methanol brought to an elevated pressure, at a temperature of 220.degree.-280.degree. C.

Abstract: There is disclosed a process for reducing the reaction time in the hydrolysis of a condensation polymer wherein molten condensation polymer is intimately admixed with a depolymerizing agent which is either (i) one of the products resulting from the complete hydrolytic depolymerization of the condensation polymer; or (ii) water. The depolymerization agent is present in the mixture in an amount which is less than the weight of the condensation polymer and the materials are intimately admixed for a time sufficient that the molecular of the condensation polymer is reduced by at least 50%. The treated condensation polymer of lower molecular weight is thereafter subjected to neutral hydrolysis. In addition to decreasing the overall time required to effect complete hydrolytic depolymerization, this process additionally permits the use of a smaller hydrolysis vessel, thereby reducing the fabrication cost of the hydrolysis unit.

Abstract: A process for the neutral hydrolytic depolymerization of condensation polymers is described. The process is conducted in a continuous manner and comprises introducing condensation polymer waste material into an aqueous hydrolysis zone at a temperature of between 200.degree. C. and 300.degree. C. and superatmospheric pressure of at least 15 atmospheres. High pressure steam is introduced into the lower portion of the hydrolysis zone underneath the level of the condensation polymer waste material. The steam serves as the principal source of heat for the hydrolysis zone. By being introduced underneath the level of the condensation polymer waste material, the steam agitates the waste material to provide heat transfer to accelerate the hydrolysis reaction. Further, a portion of the steam condenses to provide water which is a reactant in the hydrolysis reaction. An aqueous solution of the product(s) of the hydrolysis reaction is withdrawn from an upper portion of the hydrolysis zone.

Abstract: Solid scrap polyethylene terephthalate (PET) resin may be reprocessed by depolymerizing said scrap in the presence of water or methanol, recovering the monomers resulting from the depolymerization reaction and repolymerizing the monomers to form polymeric polyethylene phthalate.

Abstract: A process for the production of a crude dimethyl terephthalate suitable for hydrolyzing into a fiber grade terephthalic acid involves separating a crude ester obtained from the production of dimethyl terephthalate by the Witten process by vacuum distillation at elevated pressure in a three-column series arranged distillation system. In the first distillation column of the system the crude is separated into a methyl p-toluate-rich fraction as head product; in a second column of the series, into a fraction rich in methyl ester of terephthalaldehydic acid as head product; and in a third distillation column, a crude dimethyl terephthalate fraction. The crude dimethyl terephthalate fraction has a methyl ester of terephthalaldehydic acid content of 0.01-0.1% by weight as a head product.

Abstract: A process is described for reducing the amount of low molecular weight oligomers formed during the hydrolysis of a condensation polymer. This process comprises the neutral aqueous hydrolysis of a condensation polymer in which conditions are controlled such that the following two conditions are met:(1) the amount of water and the condensation polymer present in the hydrolysis zone are such that the least soluble final depolymerization product would not exceed its solubility limits, assuming all of the polymer is converted to final depolymerization products; and(2) temperature conditions and aqueous concentration of final depolymerization products are controlled so that at equilibrium, the amount of low molecular weight oligomers is no greater than 7% of the theoretical, based on the amount of polymer added.

Abstract: A process for the preparation of insoluble, only slightly swellable, granular polymers of basic vinyl-heterocyclic compounds and of their copolymers with up to 30% by weight of copolymerizable monomers and 0.1-10% by weight of crosslinking agent by exclusion of (atmospheric) oxygen from the mixture of monomer and crosslinking agent, without addition of any initiator or catalyst, and the use of the polymers obtained as ion exchangers, adsorbents and carriers for proteins.

Abstract: Malonic anhydride and substituted malonic anhydrides are prepared by ozonolysis of the enol-lactone dimers of ketenes. The resulting malonic anhydrides can be hydrolyzed with water to form the corresponding acid, reacted with an alcohol to yield the monoester, or reacted with an amine to yield the monoamide.

Abstract: Polyester scrap such as film (plain or silver-bearing), fabric, yarn or bottles, based primarily on polyethylene terephthalate, is depolymerized at room temperature and atmospheric pressure with a mixture of concentrated sulfuric acid and water to form crude terephthalic acid which is purified by dissolving in alkali solution, filtering to remove impurities, acidifying the filtrate to recover terephthalic acid in high yield with a purity of at least 99%.

Abstract: The invention concerns the novel compounds dialkyl 2-(3-fluoro-4-nitrophenyl)-2-methylmalonate IIIa and dialkyl 2-(3-fluoro-4-aminophenyl)-2-methylmalonate IVa useful as intermediates in an improved process for making 2-(2-fluoro-4-biphenylyl)propionic acid, known as flurbiprofen, having the formula ##STR1## and ester thereof. It has anti-inflammatory activity which is about 240 times that of aspirin and analgesic activity which is about 180 times that of aspirin in standard laboratory tests. However, despite this high activity, the toxicity (LD.sub.50) is only 1.2 to 2.4 times greater than that of aspirin in standard laboratory tests.Also within the invention is a novel method of making the above intermediates and analogs thereof useful to prepare corresponding biaryl compounds which have pharmaceutical uses.

Abstract: In a process for the preparation of fiber-grade terephthalic acid from intermediate stage crude dimethyl terephthalate, the crude dimethyl terephthalate, which has a limited content of intermediate oxidation products including a content of terephthalaldehydic acid methyl ester of up to 0.1% by weight based on the weight of the crude dimethyl terephthalate, is hydrolyzed with water at a weight ratio of the crude dimethyl terephthalate to water of between 3:1 and 0.1:1 and at a temperature between 140.degree. C. and 350.degree. C. and under a pressure required to maintain a liquid phase (e.g., from 6 to 200 bars) to produce a reaction mixture containing crystalline fiber-grade terephtalic acid and thereafter the terephthalic acid is recovered from the reaction mixture.

Abstract: Conjugated diolefins (e.g., 1,3-butadiene) are carbonylated by the palladium-catalyzed addition of carbon monoxide and an alcohol of the formula ROH (e.g., benzyl alcohol) whereby polycarboxylic esters are formed in which the pair of double bonds of the conjugated diolefin has been transformed into a moiety having the formula: ##STR1## In the process, the olefin, carbon monoxide, and alcohol are reacted in the presence of a palladium(II) salt, a copper(II) salt, and a base, at certain concentrations and at a pressure and temperature sufficient to effect the carbonylation. The resulting unsaturated diester can be hydrolyzed and hydrogenated or vice versa to obtain the corresponding linear diacid (e.g., adipic acid).