Nippon Shokubai Kagaku Kogyo Co., Ltd.

Yoshiyuki Nakanishi

Takehiko Suzuki

Takahisa Sato

Ikuo Kurimoto

Noriaki Ikeda

Yoji Akazawa

Keizo Maruyama

Youjirou Takahashi

Akira Inoue

Noboru Sugishima

Tetsuji Ono

Shigemi Osaka

Shinichi Uchida

Yasushi Fujii

Toshimasa Kushihara

Hisashi Yoshikawa

Junichi Toyoda

Shinji Ikuta

Shigeru Nakamura

A process for producing 1-aminoanthraquinone, which comprises

Process for production of 1-aminoanthraquinone

An improved process for producing maleic anhydride which comprises catalytically oxidizing benzene with a molecular oxygen-containing gas in the vapor phase in a multitubular heat-exchanger-type reactor. The process is characterized in that

Process for producing maleic anhydride

In a method for the preparation of pyromellitic acid or its anhydride by catalytic vapor phase oxidation of a tetra-C.sub.1 -C.sub.4 -alkylbenzene using a catalyst comprising catalytically active material composed of 1 to 20 parts by weight of V.sub.2 O.sub.5, 99 to 80 parts by weight of TiO.sub.2 and/or SnO.sub.2 and/or ZrO.sub.2, and per one hundred parts by weight of V.sub.2 O.sub.5, TiO.sub.2 and/or SnO.sub.2 and/or ZrO.sub.2 0.02 to 10 parts by weight, calculated as P.sub.2 O.sub.5, of a phosphorus compound, 0.01 to 5 parts by weight, calculated as Nb.sub.2 O.sub.5, of a niobium compound, 0 to 1.2 parts by weight, calculated as oxide, of at least one metal selected from the group consisting of potassium, cesium, rubidium and thallium, and 0 to 10 parts by weight, calculated as Sb.sub.2 O.sub.3, of an antimony compound, and an inert carrier supporting said catalytically active material thereon, the improvement in which said catalyst is divided into at least two layers, a layer on the gas inlet side and a layer on the gas outlet side, and (i) the content of potassium, cesium, rubidium or thallium is higher in the catalyst layer on the gas inlet side than in the catalyst layer on the gas outlet side, or (ii) the content of the phosphorus compound is lower in the catalyst layer on the gas inlet side than in the catalyst layer on the gas outlet side, or (iii) the surface area of TiO.sub.2 and/or SnO.sub.2 and/or ZrO.sub.2 is lower in the catalyst layer on the gas inlet side than in the catalyst layer on the gas outlet side.

Method for preparing pyromellitic acid and/or pyromellitic anhydride

A catalyst comprising a catalytically active material composed of 1 to 20 parts by weight as V.sub.2 O.sub.5 of vanadium oxide, 99 to 80 parts by weight of anatase-type titanium oxide being porous and having a particle diameter substantially of 0.4 to 0.7 micron and a specific surface area of 10 to 60 m.sup.2 /g, and per 100 parts by weight of the sum of said two components, 0.01 to 1 part by weight as Nb.sub.2 O.sub.5 of niobium oxide, 0.05 to 1.2 parts by weight as an oxide of at least one ingredient selected from the group consisting of potassium, cesium, rubidium and thallium, and 0.2 to 1.2 parts by weight as P.sub.2 O.sub.5 of phosphorus, and a porous carrier having an alumina content of not more than 10% by weight, a silicon carbide content of at least 80% by weight and an apparent porosity of at least 10% supporting said catalytically active material thereon, wherein the total volume of pores having a diameter of 0.15 to 0.45 micron present in the layer of the catalytically active material on the carrier is at least 50% of that of pores having a diameter of not more than 10 microns present in said layer of the catalytically active material; producing phthalic anhydride by catalytically oxidizing o-xylene or naphthalene.

Catalyst for producing phthalic anhydride

A catalyst for the production of phthalic anhydride by the catalytic vapor-phase oxidation of o-xylene or naphthalene with molecular oxygen, said catalyst comprising a catalytically active material composed of 1 to 20 parts by weight of V.sub.2 O.sub.5 of vanadium oxide and 99 to 80 parts by weight as TiO.sub.2 of anatase-type titanium oxide being porous and having a particle diameter substantially of 0.4 to 0.7 micron and a specific surface area of 10 to 60 m.sup.2 /g, and per 100 parts by weight of the sum of these two components, 0.01 to 1 part by weight as Nb.sub.2 O.sub.5 of niobium, 0.05 to 1.2 parts by weight as oxide of potassium, cesium, rubidium or thallium, 0.2 to 1.2 parts by weight as P.sub.2 O.sub.5 of phosphorus and 0.5 to 10 parts by weight as Sb.sub.2 O.sub.3 of antimony, said catalytically active material being supported on a porous carrier in an amount of 3 to 200 g/100 cc of carrier.

Catalyst for production of phthalic anhydride

A process for producing phthalic anhydride, which comprises packing a catalyst into a multitube fixed bed converter, said catalyst comprising a catalytically active material composed of 1 to 20 parts by weight as V.sub.2 O.sub.5 of vanadium oxide, 99 to 80 parts by weight of anatase-type titanium oxide being porous and having a particle diameter substantially of 0.4 to 0.7 micron and a specific surface area of 10 to 60 m.sup.2 /g, and per 100 parts by weight of the sum of said two components, 0.01 to 1 part by weight as Nb.sub.2 O.sub.5 of niobium oxide, 0.05 to 1.2 parts by weight as an oxide of at least one ingredient selected from the group consisting of potassium, cesium, rubidium and thallium, and 0.2 to 1.2 parts by weight as P.sub.2 O.sub.5 of phosphorus, and a porous carrier having an alumina content of not more than 10% by weight, a silicon carbide content of at least 80% by weight and an apparent porosity of at least 10% supporting said catalytically active material thereon, wherein the total volume of pores having a diameter of 0.15 to 0.45 micron present in the layer of the catalytically active material on the carrier is at least 50% of that of pores having a diameter of not more than 10 microns present in said layer of the catalytically active material; and passing o-xylene or naphthalene and oxygen or a molecular oxygen-containing gas through the catalyst layer at a temperature of 300.degree. to 450.degree. C., thereby catalytically oxidizing the o-xylene or naphthalene; and a catalyst suitable for performing said process.

Process for producing phthalic anhydride and catalyst therefor

A method for preparing phthalic anhydride by the catalytic vapor phase oxidation of either ortho-xylene or naphthalene, which comprises passing a gas comprising a molecular oxygen, an inert gas and a member of the group consisting of ortho-xylene and naphthalene first through a catalyst A comprising a catalytically active substance on a porous inert carrier, said catalytically active substance consisting essentially of 1 to 20 parts by weight of V.sub.2 O.sub.5, 99 to 80 parts by weight of anatase-type TiO.sub.2, and, based on the total weight of V.sub.2 O.sub.5 and TiO.sub.2, 0.01 to 1.0% by weight of Nb.sub.2 O.sub.5, 0.5 to 1.1% by weight of P.sub.2 O.sub.5, 0 to 0.25% by weight of K.sub.2 O and 0 to 0.5% by weight of Cs.sub.2 O, the total weight of the K.sub.2 O and Cs.sub.2 O being at least 0.05% by weight, 0.05 to 0.3% by weight of Na.sub.2 O and 0 to 0.5% by weight of Rb.sub.2 O, said porous inert carrier comprising essentially SiC, and thereafter through a catalyst B comprising a catalytically active substance on a porous inert carrier, said catalytically active substance consisting essentially of 1 to 20 parts by weight of V.sub.2 O.sub.5, 99 to 80 parts by weight of anatase-type TiO.sub.2, and, based on the total weight of the V.sub.2 O.sub.5 and TiO.sub.2, 0.01 to 1.0% by weight of Nb.sub.2 O.sub.5, 1.2 to 2.5% by weight of P.sub.2 O.sub.5, 0 to 0.25% by weight of K.sub.2 O and 0 to 0.5% by weight of Cs.sub.2 O, the total weight of the K.sub.2 O and Cs.sub.2 O being at least 0.05% by weight, 0.05 to 0.3% by weight of Na.sub.2 O and 0 to 0.5% by weight of Rb.sub.2 O, said porous inert carrier comprising essentially SiC.

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Himeji, Japan

Yoshiyuki Nakanishi