Teijin Petrochemical Industries, Ltd.

Tokuji Sakai

Tamio Onodera

Yasuo Yamasaki

Koji Sumitani

Kimihiko Sato

Isao Hirose

Tamio Amemiya

Kiji Sumitani

Minekazu Sueoka

A process for producing a crystalline aluminosilicate zeolite characterized by having (a) a silica/alumina mole ratio of from 10 to 100, (b) X-ray lattice distances d shown in Table A of the specification, and (c) a specific n-hexane adsorption, under limited measuring conditions, of at least 0.07 g/g, which comprises maintaining a silica source, an alumina source, and a zeolite selected from zeolites ZSM-5 and zeolites having said characteristics, in an aqueous solution containing 1 to 200 millimoles, per gram of said zeolite, of an alkali metal hydroxide under such temperature, pressure and time conditions as to produce a crystalline aluminosilicate zeolite; and a crystalline aluminosilicate zeolite characterized by having aforesaid properties (a) to (c) and (d) a (2-methylpentane/cyclohexane) adsorption ratio of from 1.1 to 1.6.

Preparation of crystalline aluminosilicate zeolite, and its product

A process for producing 2,6-naphthalenedicarboxylic acid which comprises oxidizing 2,6-diisopropylnaphthalene or its oxidation product as a starting material with molecular oxygen in a reaction medium containing at least 50% by weight of an aliphatic monocarboxylic acid having not more than 3 carbon atoms in the presence of an oxidation catalyst comprising (A) at least one heavy metal element selected from the group consisting of cobalt and manganese, and (B) bromine element, the 2,6-diisopropylnaphthalene and/or its oxidation product being used in a proportion of 0.1 to 5 moles per gram-atom of the heavy metal element of the oxidation catalyst.

Process for producing 2,6-naphthalene-dicarboxylic acid

A novel crystalline aluminosilicate zeolite characterized by having a composition of the following general formula expressed in terms of the mole ratios of oxides in the anhydrous state

Novel crystalline aluminosilicate zeolites and process for production

A process for producing a crystalline zeolite TPZ-12, which comprises maintaining a starting mixture at a temperature of at least 80.degree. C. for a period sufficient to produce zeolite crystals, said starting mixture consisting of

Production of crystalline zeolites

A novel crystalline aluminosilicate zeolite characterized by having

Crystalline aluminosilicate zeolite and process for production thereof

A catalyst composition comprising (i) a crystalline aluminosilicate selected from the group consisting of zeolite ZSM-5, zeolite ZSM-11, zeolite ZSM-12, zeolite ZSM-35 and zeolite ZSM-38 and having a silica/alumina mole ratio of 20 to 1,000; and (ii) at least two metals which are (a) platinum and (b) at least one other metal selected from the group consisting of titanium, chromium, zinc, gallium, germanium, strontium, yttrium, zirconium, molybdenum, palladium, tin, barium, cerium, tungsten, osmium, lead, cadmium, mercury, indium, lanthanum and beryllium. This catalyst composition is useful particularly for the isomerization of aromatic hydrocarbons and reforming of naphtha.

Catalyst composition

In a process for producing p-xylene which comprises catalytically methylating toluene with a methylating agent in the gaseous phase, the improvement wherein (a) said methylation is carried out continuously in a multi-stage reaction system consisting of a plurality of separate series-connected fixed catalyst layers without separating the resulting xylenes in an intermediate stage, (b) said toluene is fed together with hydrogen gas into only the first-stage fixed catalyst layer and passed successively through the subsequent fixed catalyst layers, the amount of toluene fed being such that the total weight hourly space velocity of toluene is from 1 to 300 hr.sup.-1, (c) said methylating agent is fed into each of said fixed catalyst layers, if desired together with hydrogen gas, the amount of the methylating agent fed into each catalyst layer being 0.01/t moles to 1/t moles, in which t is the number of methyl groups in the methylating agent, per mole of toluene fed into the first-stage catalyst layer, and the total amount of the methylating agent fed into all of the catalyst layers being within the range of 0.1/t moles to 2/t moles, in which t is as defined, per mole of toluene fed into the first-stage catalyst layer, and (d) each fixed catalyst layer is filled with a catalyst composed of a crystalline aluminosilicate containing magnesium oxide or lanthanide oxide.

Process for producing p-xylene

In a process for isomerization of xylenes which comprises contactng an aromatic hydrocarbon stock mainly containing xylene isomers not attaining a thermodynamic equilibrium composition with a catalyst composition containing a crystalline aluminosilicate at an elevated temperature in the vapor phase in the presence of hydrogen, the improvement wherein said catalyst composition comprises a crystalline aluminosilicate having a silica/alumina mole ratio of at least 10 and contains at least two metals which are (a) platinum and (b) at least one metal selected from the group consisting of titanium, chromium, zinc, gallium, germanium, strontium, yttrium, zirconium, molybdenum, palladium, tin, barium, cesium, cerium, tungsten, osmium, lead, cadmium, mercury, indium, lanthanum, beryllium, lithium and rubidium.

Isomerization of xylene

In a process for dealkylating a hydrocarbon material containing at least one alkyl-substituted aromatic hydrocarbon having bonded to the aromatic ring at least one alkyl group with at least 2 carbon atoms in the gaseous phase in the presence of hydrogen using a hydro-dealkylation catalyst, the improvement wherein (a) said hydro-dealkylation catalyst is composed of a crystalline aluminosilicate having a silica/alumina mole ratio of from 20 to 200 and containing a noble metal selected from platinum, palladium, rhodium and iridium, and (b) said dealkylation is carried out at a temperature of 250.degree. C. to 420.degree. C. and a pressure of not more than 100 psig, thereby selectively removing said alkyl group containing at least 2 carbon atoms from said alkyl-substituted aromatic hydrocarbon.

Process for selective dealkylation of alkyl-substituted aromatic

A process for isomerizing xylenes, which comprises

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Matsuyama, Japan

Tokuji Sakai