Abstract: A process for producing an aromatic carboxylic acid by a liquid phase oxidation of an alkylaromatic compound with molecular oxygen in a reaction solvent comprising a lower aliphatic carboxylic acid in the presence of an oxidation catalyst, in which an aromatic carboxylic acid having an improved hue of the powdery product thereof and exhibiting an improved light transmittance when dissolved in an aqueous solution of a base can be produced efficiently in a simple manner by suppressing contamination due to the intermediates and by-products formed by side reactions, the said process comprising performing the liquid phase oxidation of the alkylaromatic compound in the presence of a hydrogen gas-treated liquid containing the catalyst.

Abstract: A method for producing aryl alkyl hydroperoxides which comprises selectively oxidizing an aryl alkyl hydrocarbon having the formula: ##STR1## wherein P and Q are hydrogen or an alkyl and may be the same or different from each other; x is an integer of 1-3; and Ar is an aromatic hydrocarbon group having a valence of x, with an oxygen-containing gas in the presence of a transition metal complex which contains, as a ligand, a cyclic polyfunctional amine compound having at least three nitrogen atoms in the ring forming molecular chain or an open chain polyfunctional amine compound having at least three nitrogen atoms in the main chain of the molecule.

Abstract: A method for producing aryl alkyl hydroperoxides which comprises selectively oxidizing an aryl alkyl hydrocarbon having the formula: ##STR1## wherein P and Q are hydrogen or an alkyl and may be the same or different from each other; x is an integer of 1-3; and Ar is an aromatic hydrocarbon group having a valence of x, with an oxygen-containing gas in the presence of a transition metal complex which contains, as a ligand, a cyclic polyfunctional amine compound having at least three nitrogen atoms in the ring forming molecular chain or an open chain polyfunctional amine compound having at least three nitrogen atoms in the main chain of the molecule.

Abstract: The invention provides a method for purifying a crude naphthalenedicarboxylic acid comprising the steps of mixing a crude naphthalenedicarboxylic acid and a water/alcohol solvent to esterify a part of the naphthalenedicarboxylic acid, thereby dissolving a naphthalenedicarboxylic ester into the solvent, and then contacting the resulting reaction mixture with hydrogen in the presence of a hydrogenation catalyst to hydrogenate impurities which are contained in the crude naphthalenedicarboxylic acid and which are capable of being hydrogenated, thereby dissolving and removing hydrogenation products into the water/alcohol solvent. A mixture of a naphthalene dicarboxylic acid and a naphthalenedicarboxylic ester with reduced impurity contents, or a high-purity naphthalenedicarboxylic acid can be obtained.

Abstract: A method for producing aryl alkyl hydroperoxides which comprises selectively oxidizing an aryl alkyl hydrocarbon having the formula: ##STR1## wherein P and Q are hydrogen or an alkyl and may be the same or different from each other; x is an integer of 1-3; and Ar is an aromatic hydrocarbon group having a valence of x, with an oxygen-containing gas in the presence of a transition metal complex which contains, as a ligand, a cyclic polyfunctional amine compound having at least three nitrogen atoms in the ring forming molecular chain or an open chain polyfunctional amine compound having at least three nitrogen atoms in the main chain of the molecule.

Abstract: In the production of polyethylene naphthalate of the present invention, the esterification reaction between naphthalenedicarboxylic acid and ethylene glycol is conducted while causing water to be present in a reaction system from a start of reaction, in the presence of at least one catalyst selected from the group consisting of nitric, carboxylic, phosphoric and hydrogenphosphoric acid metal salts and alkyl amines according to necessity, to thereby attain an esterification ratio of 45 to 80%, so that a liquid mixture of naphthalenedicarboxylic acid esterification reaction products containing naphthalenedicarboxylic acid, carboxyl-hydroxyethoxycarbonylnaphthalene and bis(hydroxyethoxycarbonyl)naphthalene is obtained. Subsequently, a crystallized reaction product is separated from this liquid mixture to thereby obtain a mixture of esterification reaction products. Thereafter, this mixture having ethylene glycol added thereto according to necessity is subjected to polycondensation.

Abstract: A lubricating oil containing an aromatic ether compound represented by the general formula, (R.sup.1).sub.n Ph--O-- (R.sup.2 O).sub.m --R.sup.3, wherein R.sup.1 stands each independently for a particular hydrocarbon group, an etheric oxygen-containing hydrocarbon group, an alkoxyl group, or a halogen-substituted hydrocarbon group, R.sup.2 stands each independently for an alkylene group having 2 to 4 carbon atoms, R.sup.3 stands for a hydrocarbon group having 1 to 12 carbon atoms, Ph stands for an aromatic substituent, n stands for an integer of from 1 to 5, and m stands for an integer of from 1 to 30. The lubricating oil has excellent lubricating property, cleaning property and electrically insulating property, exhibits excellent sealing property owing to its high viscosity and wear resistance, and further exhibits excellent compatibility with R-134a, etc. The lubricating oil can be favorably used for the refrigerators such as of electric refrigerators and room air conditioners that use R-134a as a coolant.

Abstract: A process for producing an alkyl-substituted aromatic hydrocarbon, which comprises alkylating an aromatic hydrocarbon with an alkylating agent in the presence of a heteropoly-acid or a salt thereof such as phosphorus tungstate and silicon tungstate as a catalyst. The process is particularly useful for preparing alkyl-substituted naphthalene or naphthalene derivatives.

Abstract: In a process of producing isopropylnaphthols by oxidizing diisopropylnaphthalenes with molecular oxygen in a liquid phase to provide a reaction mixture which contains therein diisopropylnaphthalene monohydroperoxides and then acid decomposing the monohydroperoxides to isopropylnaphthols, the improvement comprising separating an organic layer from the reaction mixture, adding lower aliphatic alcohols of 1-4 carbons to the organic layer, crystallizing the diisopropylnaphthalenes while allowing the diisopropylnaphthalene monohydroperoxides to remain dissolved in the lower aliphatic alcohols, thereby to separate the monohydroperoxides from the diisopropylnaphthalenes.A further improvement in the process comprises crystallizing the isopropylnaphthols from aromatic hydrocarbons of 6-12 carbons.

Abstract: In a process for producing an alkyl group-substituted aromatic hydrocarbon according to the present invention, (i) an aromatic hydrocarbon is reacted with (ii) an alkylating agent selected from the group consisting of olefins, lower aliphatic alcohols and alkyl halides in the presence of a mordenite-type zeolite catalyst treated with a fluorine-containing compound, and therefore the conversion of the aromatic compound can be increased and further it is possible to introduce the specific number of alkyl groups into the specific position of the aromatic compound.In particular, when biphenyl is used as the aromatic hydrocarbon and propylene is used as the alkylating agent, p,p'-diisopropylbiphenyl can be obtained in a high yield and high selectivity.

Abstract: A process is disclosed which is capable of producing p,p'-biphenol of high purity by the dealkylation reaction of 3,3',5,5'-tetra-t-butyl-4,4'-dihydroxybiphenyl and which yet allows isobutene to be recovered in high yield. The process performs the dealkylation reaction of 3,3',5,5'-tetra-t-butyl-4,4'-dihydroxybiphenyl in the presence of an acid catalyst using as a solvent a saturated hydrocarbon having a boiling point of 190.degree. C. or above, an alicyclic hydrocarbon having a boiling point of 190.degree. C. or above, a hydrocarbon with an iodine value of no more than 1, sulfolane, or a mixture of these solvents. Also disclosed is a process for producing p,p'-biphenol from a mixture of 2,6-di-t-butyl-phenol and 3,3',5,5'-tetra-t-butyl-4,4'-diphenoquinone or from a mixture of 2,6-di-t-butylphenol, 3,3',5,5'-tetra-t-butyl-4,4'-diphenoquinone and 3,3',5,5'-tetra-t-butyl-4,4'-dihydroxybiphenyl.