Ube Industries, Inc.

Ems-chemie Ag

Shuji Tanaka

Keigo Nishihira

Ryoji Sugise

Takashi Doi

Katsumasa Harada

Hirofumi Ii

Shinichi Yoshida

Satoru Fujitsu

Masayuki Nishio

Yuki Nishida

Koichi Kashiwagi

Tsunao Matsuura

Sadao Niida

Hiroshi Yoshida

Kozo Fujii

Mamoru Nakai

Hiroyuki Sawada

Yoichi Imbe

Teruhiko Inoue

Katsuhiko Mizutare

Kohichi Kashiwagi

Kazuaki Mii

Toshihiko Sumida

Masahiro Kondo

Tetsuro Kawashita

Yutaka Asada

Koji Abe

Sumio Umemura

Masato Murakami

Tokuo Matsuzaki

Akinori Shiotani

Masaki Yoshio

Yoshiaki Kuroki

Toshio Kurafuji

Noriaki Manada

Hiroshi Kofuji

Genji Koga

Hideya Yoshitake

Takayoshi Kaneko

Katsutoshi Washio

Kiyosi Oomori

Hiroyoshi Nakamura

Shin-ichi Yoshida

Tamiko Nishihira

Kunioki Kodama

Ii Hirofumi

Kazuo Miyamoto

Shin-Ichi Yoshida

Disclosed is a process for preparing a diaryl oxalate which comprises the step of transesterifying a dialkyl oxalate or/and an alkylaryl oxalate with an aryl alcohol in the presence of a tetra(aryloxy)titanium as a catalyst, wherein the tetra(aryloxy)titanium is fed into a reaction system of the transesterification as an aryl alcohol solution of the tetra(aryloxy)titanium which is prepared by reacting a tetraalkoxy titanium and an excess amount of the aryl alcohol and removing a by-producing alkyl alcohol.

Process for preparing diaryl oxalate

An alkyl nitrite is produced with high efficiency by bringing a nitrogen monoxide gas into contact with an aqueous solution of an alkyl alcohol and nitric acid in a reactor, which aqueous solution may be a liquid fraction generated in an alkyl nitrite-production process in which an alkyl alcohol is reacted with nitrogen monoxide and oxygen in a reaction column

Process for producing alkyl nitrite

In the process for producing a cyclododecanone by isomerizing an epoxycyclododecane-containing starting material in the presence of an isomerization reaction catalyst containing lithium bromide and/or lithium iodide, in order to perform the reaction with high efficiency (high reaction rate) and high selectivity and stably produce a high-purity cyclododecanone in industry while maintaining a high-level reaction rate, the epoxycyclododecane-containing starting material is produced by contacting an epoxycyclododecadiene with hydrogen in the presence of a hydrogen-reduction catalyst and has a content of the hydroxyl group-containing cyclododecane compounds contained in the epoxycyclododecane-containing starting material controlled to 5 mol % or less.

Process for preparation of cyclododecanone

An alkyl nitrite is produced with high efficiency by bringing a nitrogen monoxide gas into contact with an aqueous solution of an alkyl alcohol and nitric acid in a reactorwhich aqueous solution may be a liquid fraction generated in an alkyl nitrite-production process in which an alkyl alcohol is reacted with nitrogen monoxide and oxygen in a reaction column

A process for preparing polycarbonate is composed of the steps of transesterifying a dialkyl oxalate and a phenolic compound to give a diaryl oxalate; decarbonylating the diaryl oxalate to give a diaryl carbonate; reacting the diaryl carbonate with a polyvalent hydroxyl compound in the presence of a catalyst containing an amine compound or an ammonium compound to give the polycarbonate, removing a phenolic by-product/amine by-product mixture; collecting the mixture; purifying the mixture so that the amount of the amine by-product in the mixture is reduced to give a phenolic by-product mixture not containing the amine by-product in an amount of more than 600 ppm; and, utilizing thus purified phenolic mixture as a whole or a part of the phenolic compound in the first step.

Process for producing polycarbonate

A refined dihydroxyaryl compound, for example, catechol, having a high degree of purity and a very low metal content is produced by evaporating a starting dihydroxyaryl compound in a distillation column, condensing the vapor fraction in a condenser connected to a top outlet of the distillation column, and collecting the condensed fraction from the condenser into a storage tank through a conduit, wherein the condenser and optionally the conduit and/or the storage tank have inside surfaces thereof formed from a metal material containing at least 25% by weight of nickel, and the condensed dihydroxyaryl compound fraction is brought into contact with the specific nickel (25% or more)-containing metal inside surface.

Method of refining dihydroxyaryl compound

A cyclododecanone compound is continuously produced by an isomerization reaction of a corresponding epoxycyclododecane compound in the presence of a catalyst including lithium bromide and/or lithium iodide, the isomerization reaction being carried out by passing a reaction mixture containing the epoxycyclododecane compound and the catalyst through a continuous reaction apparatus including at least one tubular reactor preferably at a temperature of 100 to 350&deg; C.

Method of continuously producing a cyclododecanone compound

A composition consisting essentially of a diaryl carbonate and contains a furan ring-containing compound in an amount of not more than 1 ppm is favorably employable for producing less colored polycarbonate.

Diaryl carbonate product and production of polycarbonate

A cyclododecanone compound is continuously produced by feeding a liquid feed containing a corresponding epoxycyclododecane compound and LiBr and/or LiI into a frontmost reaction region of a plurality of reaction regions connected to each other in series; successively passing the liquid feed through the series of reaction regions to catalytically isomerize the epoxycyclododecane compound into a corresponding cyclododecanone compound; and collecting the resultant reaction mixture containing the target cyclododecanone compound from a rearmost reaction region of the series of reaction regions.

Process for continuously producing a cyclododecanone compound

A cyclododecanone compound is produced in a high reaction rate, with a high conversion of the starting compound, and with a high selectivity to and a high yield of the target compound by isomerizing an epoxycyclododecane compound in the presence of a catalyst comprising lithium bromide and/or lithium iodide, without using a solvent or in a non-polar solvent, in an inert gas atmosphere, while substantially no polymeric compounds having a high boiling temperature is produced.

Method and producing cyclododecanone compound

An alkyl nitrite can be produced on an industrial scale with a high efficiency and with a low yield of by-products by the process wherein nitrogen oxide-containing feed gas is brought into an alkyl alcohol liquid in a distillation column reactor while circulating a liquid fraction, produced in the reactor and containing the alkyl alcohol, through a circulation path including a lower section of the reactor and a cooler to remove the reaction heat vigorously generated in the reactor, and while controlling the weight ratio of the circulating liquid fraction to the total alkyl alcohol fed into the reactor to 50:1 to 200:1, the molar ratio of the total alkyl alcohol fed to the reactor and contained in the circulating liquid fraction to nitrogen oxide in the feed gas to 20:1 to 150:1, and the content of the alkyl alcohol in the liquid fraction to 15 to 60% by weight; and the resultant gas fraction containing the target alkyl nitrite is collected from the reactor.

Process for producing a diaryl oxalate

A diaryl carbonate is produced by decarbonylating a diaryl oxalate, which can be prepared by transesterification of a dialkyl oxalate with a hydroxyaryl compound, in the presence of a catalyst, while removing the resultant carbon monoxide as a by-product, and then optionally refined by an evaporation and/or distillation, and then the resultant diaryl carbonate is condensation-polymerized with a polyhydroxyl compound, while recovering a resultant hydroxyaryl compound from the reaction system, to produce a polycarbonate.

Process for producing a polycarbonate

A catalyst composed of an organic phosphorus compound having a trivalent or pentavalent phosphorus atom and at least one carbon-phosphorus bonding or a combination of the organic phosphorus compound and a halogen atom-containing compound is effective for decarbonylation, that is, for releasing carbon monoxide from a compound containing a moiety of --CO--CO--O-- in its molecular structure.

Catalyst for decarbonylation reaction

A process for preparing a diaryl carbonate from a diaryl oxalate in a liquid phase by decarbonylation is conducted by the steps of:

Process for preparing diaryl carbonate

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Ube, Japan

Shuji Tanaka