Mitsubishi Petrochemical Company Limited

Takahiro Sugawara

Hiroshi Iwane

Naoki Suzuki

Makoto Imanari

Kimiko Kaneko

Satoshi Ohtaka

Masashi Inaba

Tadamichi Aoki

Tadashi Ayusawa

Mitsugi Kataoka

Miwa Shirasaki

Katsufumi Kujira

Tomoya Sakata

A process for producing 2,6-naphthalenedicarboxylic acid by oxidizing 2,6-dimethylnaphthalene by molecular oxygen in the presence of a catalyst including cobalt, manganese and bromine. The oxidation reaction is performed by using a 2,6-dialkylnaphthalene mixture of 2,6-dimethynaphthalene and a small amount of 2,6-diisopropylnaphthalene as a raw material. Thus, the desired 2,6-naphthalenedicarboxylic acid can be produced at a high yield.

Process for producing 2,6-naphthalenedicarboxylic acid

A process for purifying a crude naphthalenedicarboxylic acid containing impurities and coloring substances obtained by the oxidation of a di-substituted naphthalene, dispense with the use of a large amount of alkali or acid, and producing a naphthalenedicarboxylic acid having a high purity and good color effectively and in a high recovery is disclosed, which comprises dissolving the crude naphthalenedicarboxylic acid in a mixed solvent comprising an amine compound and an alcohol and conducting crystallization.

Process for purification of naphthalenedicarboxylic acid

Process for para-methylolating phenol compounds

A process for producing a polyhydroperoxy aromatic compound by oxidation of an aromatic hydrocarbon, e.g., 4,4'-diisopropylbiphenyl and 4,4'-diisopropylnaphthalene, with molecular oxygen is disclosed, in which the oxidation is carried out in the presence of a metal ion selected from cobalt, nickel, zinc and lead ions. Even in using a reaction apparatus made of an iron-containing metal generally employed in industry, a high conversion of secondary alkyl groups can be reached, and the desired polyhydroperoxy aromatic compound can be obtained in a high yield.

Process for producing polyhydroperoxy aromatic compound

A process for preparing 2,6-naphthalenedicarboxylic acid comprising oxidation reaction of 2,6-diisopropylnaphthalene or an oxidation product thereof with molecular oxygen in a solvent containing an aliphatic carboxylic acid in the presence of a catalyst comprising cobalt and manganese as heavy metals and a bromine compound is disclosed, in which said oxidation reaction is carried out in the presence of at least one nitrogen-containing compound selected from the group consisting of a pyridine compound, ammonia, a carboxylic acid ammonium salt, urea, a urea derivative, an amine, and a carboxylic acid amide. 2,6-Naphthalenedicarboxylic acid can be obtained at higher purity and in increased yield.

Process for preparing 2,6-naphthalenedicarboxylic acid

A process for preparing 4,4'-dihydroxybiphenyl comprising oxidizing 4,4'-diisopropylbiphenyl with molecular oxygen and decomposing the resulting oxidation product in the presence of an acid catalyst is disclosed, in which oxidation of 4,4'-diisopropylbiphenyl is carried out in the presence of ammonia or an ammonium salt. The oxidation product has an increased selectivity of 4,4'-diisopropylbiphenyl dihydroperoxide and, therefore, produces the desired product in high yield upon acid decomposition.

Process for preparing 4,4'-dihydroxybiphenyl

A process for preparing p-hydroxybenzyl alcohol or a derivative thereof comprising reacting a phenol and a formaldehyde source under a basic condition is disclosed, wherein the reaction is carried out in an alcoholic organic solvent in the presence of a crown ether. The process achieves high selectivity toward the para position without involving high cost.

Process for preparing p-hydroxybenzyl alcohol

A process for preparing 4,4'-dihydroxydiphenylmethane, which comprises reacting phenol with formaldehyde in the presence of an acidic catalyst and separating the aimed 4,4'-dihydroxydiphenylmethane from the crude dihydroxydiphenylmethane thus obtained, is disclosed. According to this process, 4,4'-dihydroxydiphenylmethane can be separated from its isomers and oligomers at a high purity and at a high yield, compared with those achieved by known methods. Thus highly useful 4,4'-dihydroxydiphenylmethane can be advantageously prepared on an industrial scale.

Process for preparing 4,4'-dihydroxydiphenylmethane

A process for preparing p-cumylphenol which comprises reacting phenol and .alpha.-methylstyrene in the presence of an inorganic solid acid catalyst having an acid point of an acid strength Ho of up to -3, for example, activated clay and recovering the aimed p-cumylphenol from the reaction mixture thus obtained by distilling the same while introducing an inert gas such as nitrogen and/or steam into the distillation system is disclosed. The p-cumylphenol thus obtained has a high purity and an improved color compared with those obtained by conventional methods.

Process for preparing p-cumylphenol

A process for producing tert-amylphenols is described, comprising reacting isoamylene with phenols in the presence of an inorganic solid acid catalyst or an acidic ion exchange resin catalyst. This process permits efficient production of tert-amylphenols, i.e., 2,4-di-tert-amylphenol and p-tert-amylphenol. These tert-amylphenols are useful as starting materials for preparation of color formers for color photography, additives for resins, oil-soluble dyes, additives for lubricating oils, etc.

Process for producing tert-amylphenols

A process for producing 4,4'-dihydroxydiphenyls is disclosed, which comprises dimerizing alkylphenols in an aqueous solution of pH 7 to 12 containing a surfactant in the presence of an oxidizing agent, wherein the dimerization is conducted in the presence of a copper compound and a basic boron compound or a mixture of a basic substance and a boron compound. According to this process, the desired 4,4'-dihydroxydiphenyls can be easily obtained in high yield.

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Ibaraki, Japan

Takahiro Sugawara