Nippon Shokubai Co., Ltd.

Nippon Shokubai Kagaku Kogyo Co., Ltd.

Yuuji Shimasaki

Michio Ueshima

Hitoshi Yano

Youichi Hino

Kimio Ariyoshi

Akira Kurusu

Hideaki Tuneki

Hideaki Tsuneki

Akio Naka

Yoshinari Yamaguchi

Hideyuki Kambe

Tetsuro Hayashi

Hideyuki Kanbe

Nobuyuki Harada

Koichi Yamamoto

Yutaka Morimoto

Hideyuki Nishibayashi

Toshiaki Kuriyama

Ryuichi Ishikawa

Daijo Tomihisa

Shinji Takasaki

Shukichi Ugamura

Teruo Kamei

Hideki Masada

Masako Hokazono

In a fixed-bed flow reaction using a multitubular heat exchange type reactor, an object of the present invention is to provide a novel packing for a reaction tube, which can control the reaction ratio in the vicinity of the reaction tube inlet, reduce the load unevenly placed on the catalyst in the reaction region, and distribute the load on the entire catalyst layer, a heat exchange type reactor, and a reaction method using the reaction tube. The packing for a reaction tube of the present invention is characterized in that the volume is continuously or step-by-step decreased from one end part or midway toward the other end part.

Packing for reaction tube, reaction tube, and reaction method using same

Here is provided a process capable of efficiently carrying out a gas-phase dehydration reaction comprising contacting a raw material gas with a solid oxide catalyst containing an alkali metal element to allow reaction to progress by inhibiting decomposition of the raw material and the objective product. This process comprises using a sintered oxide comprising an alkali metal element and silica and/or alumina as a loading material for preheating of the raw material gas and/or as a supporting material for fixation of the position of the catalyst.

Gas-phase dehydration reaction process

A process for recovering N-vinyl-2-pyrrolidone is provided which allows to recover N-vinyl-2-pyrrolidone efficiently and steadily and in high purity by continuous distillation from a mixed liquid containing N-vinyl-2-pyrrolidone, N-(2-hydroxyethyl)-2-pyrrolidone, compounds having a higher boiling point than N-vinyl-2-pyrrolidone and water. The process includes continuously distilling the mixed liquid using a distilling column, controlling the temperature of the bottom liquid of the distilling column at 180&deg; C. or less.

Process for recovering N-vinyl-2-pyrrolidone

The present invention provides a production process for a vinylpyrrolidone polymer which process prevents the polymerization reaction of N-vinylpyrrolidone from being hindered by by-products (as formed by nucleomethylation of N-vinylpyrrolidone) or &ggr;-butyrolactone, and therefore enables to obtain a vinylpyrrolidone polymer that has a desired molecular weight and involves only a small amount of residual monomers, wherein the vinylpyrrolidone polymer can display excellent properties even if the vinylpyrrolidone polymer is, for example, crosslinked to convert it into a water-absorbent resin. The production process for a vinylpyrrolidone polymer comprises the step of polymerizing a polymerizable monomer component or components which include N-vinylpyrrolidone, wherein: the N-vinylpyrrolidone as used is N-vinylpyrrolidone having a &ggr;-butyrolactone content of not more than 500 ppm; and/or the N-vinylpyrrolidone as used is N-vinylpyrrolidone obtained without using acetylene as a raw material.

Production process for vinylpyrrolidone polymer

Provided are an industrially advantageous process for producing a polymer of polyvinyl ether at a temperature of not lower than a room temperature for short time, and a catalyst used for the process. The above process is characterized by using an acid clay mineral subjected to acid treatment as a catalyst to polymerize vinyl ether.

Production process for polyvinyl ether and catalyst used for the process

A reaction mixture in a gas form which is obtained by intramolecular dehydration of glycol ether in a gas phase is liquidized and collected by using as a collecting agent the glycol ether which is a raw material of the reaction mixture. The collected liquid thus obtained is continuously distilled by using a continuous distillation column so that a distillate containing alkyl vinyl ether and water is obtained, while a bottom product containing glycol ether is obtained. The distillate is left to stand in a separation vessel whereby separating into an oleaginous layer and an aqueous layer, so that alkyl vinyl ether is collected as the oleaginous layer. On the other hand, in the case where the bottom product contains water, the bottom product is continuously distilled together with an azeotrope former by using a continuous distillation column whereby a distillate containing an azeotrope of water and the azeotrope former, so that glycol ether is collected as a bottom product. By doing so, a method whereby alkyl vinyl ether as well as glycol ether which is the raw material and the collecting agent are efficiently collected, purified, and recovered is realized.

Method for recovering alkyl vinyl ether

There is provided a process for producing a tertiary amine compound in one step without using any subsidiary raw material or any solvent, by subjecting a secondary amine compound and an alcohol to an intermolecular dehydration reaction in a gas phase. The process uses, as a catalyst, an oxide containing an alkali metal element and/or an alkaline earth metal element and silicon.

Process for production of tertiary amine compound

There is provided a process for producing a cyclic N-vinyl carboxylic acid amide stably in safety and low cost, using, as starting raw materials, a cyclic carboxylic acid ester and monoethanolamine both available inexpensively and easily. The process comprises subjecting a cyclic carboxylic acid ester and monoethanolamine to an intermolecular dehydration reaction (a first-step reaction) in a liquid phase to produce a cyclic N-(2-hydroxyethyl) carboxylic acid amide and then subjecting the cyclic N-(2-hydroxyethyl) carboxylic acid amide to an intramolecular dehydration reaction (a second-step reaction) in a gas phase in the presence of an oxide catalyst containing an alkali metal element and/or an alkaline earth metal element and silicon, to produce a cyclic N-vinyl carboxylic acid amide.

Process for production of cyclic N-vinyl carboxylic acid amide

There is provided a simple and rational process for production of a vinyl ether, which comprises subjecting a 2-hydroxyalkoxy compound having, in the molecule, at least one 2-hydroxyalkoxy group and at least one functional group selected from the group consisting of a hydroxyl group and an amino group, to an intramolecular dehydration reaction in a gas phase to convert the compound into a corresponding functional group-containing vinyl ether in one step without using any subsidiary raw material or any solvent. The process is characterized by using, as a catalyst, an oxide containing an alkali metal element and/or an alkaline earth metal element and silicon.

Process for production of vinyl ether

The present invention provides a process for producing an N-vinyl compound, which comprises subjecting an N-(-alkoxyalkyl) compound to gas phase intramolecular alcohol elimination to convert said compound to an N-vinyl compound directly in one step, wherein a solid oxide containing phosphorus and an alkali metal and/or an alkaline earth metal is used as a catalyst. This process need not use any solvent or any auxiliary raw material and consequently can produce an N-vinyl compound simply and safely without generating any waste material derived from the auxiliary raw material.

Process for production of N-vinyl compound

The present invention provides a process for producing an unsaturated ether, which comprises subjecting a glycol ether to intramolecular dehydration in a gas phase in the presence of a catalyst to convert the glycol ether into an unsaturated ether directly in a one-step reaction. As the catalyst, an oxide containing, for example, silicon and an alkali metal is used. The process, which uses no auxiliary raw material, can produce an unsaturated ether (a vinyl ether and/or an allyl ether) simply and safely without generating any waste material derived from the auxiliary raw material.

Process for production of unsaturated ether and catalyst used for

The present invention provides a catalyst which is an oxide comprising silicon and at least one element selected from the group consisting of alkali metals and alkaline earth metals and which is used for gas-phase intramolecular dehydration of a tertiary N-(2-hydroxyalkyl) carboxylic acid amide to synthesize a tertiary N-alkenyl carboxylic acid amide. This catalyst enables continuous and efficient production of a tertiary N-alkenyl carboxylic acid amide from a tertiary N-(2-hydroxyalkyl) carboxylic acid amide without using any auxiliary raw material, and consequently allows for simple and safe production of a tertiary N-alkenyl carboxylic acid amide without generating any by-product (waste product) derived from the auxiliary raw material.

Catalyst for production of tertiary N-alkenyl carboxylic acid amide, and

A method for preparing isocyanates by the thermal decomposition of carbamates in the presence of a sintered oxide as catalyst under gaseous phase condition. The sintered oxide is composed of at least one element selected from the group consisting of boron, aluminum, silicon, tin, lead, antimony, zinc, yttrium, lanthanum, titanium, zirconium, niobium, tungsten, and iron. The sintered oxide may be composed of at least one element selected from the group consisting of phosphorus, alkali metal element, and alkaline earth metal element.

Process for preparing isocyanates using sintered oxides

In a process for preparing alkylene sulfides through the intramolecular dehydration reaction of mercaptoalkanols in a gaseous phase, catalysts are used, which are represented by the formula: M.sub.a X.sub.b Y.sub.c O.sub.d, where M represents at least one element selected from the group of alkali metals, alkaline earth metals and thallium; X represents at least one element selected from the group of Al, B, Si and P; Y represents at least one element selected from the group consisting of lanthanides, IIIA group, IVA group, VA group, IIIB group, IVB group, VB group and VIB group, excluding an element contained in M or X; O represents oxygen; and a and b are numerical values not equal to 0; b=0.2-100 and c=0-50 when a=1; and d is a numerical value determined according to a, b and c.

Process for preparing alkylene sulfides

A method of producing ethylenediamines represented by the general formula ##STR1## wherein R represents a hydrogen atom, or a methyl or ethyl group, which comprises reacting an aziridine compound of the general formula ##STR2## wherein R is as defined, with ammonia in the gaseous phase in the presence of a solid acid catalyst. In another aspect, a method of producing ethylenediamines of the general formula (I), which comprises reacting a reaction product containing an aziridine compound of the general formula (II), obtained by the gaseous phase intramolecular dehydration reaction of an alkanolamine represented by the general formula ##STR3## wherein X represents the OH group or the NH.sub.2 group, Y represents the NH.sub.2 group when X is the OH group and the OH group when X is the NH.sub.2 group, and R is as defined, in the presence of a catalyst A, with ammonia in the gaseous phase in the presence of a solid acid catalyst (catalyst B).

Growing community of inventors

Otsu, Japan

Yuuji Shimasaki