Abstract: Alkylene glycol is oxidized in a vapor phase in the presence of alcohol (a), oxygen, and a catalyst (a) (primary reaction). &agr;-oxoaldehyde, and alcohol (b) or olefin, are oxidized in a vapor phase in the presence of oxygen and a catalyst (b) (secondary reaction). A molar ratio of the alkylene glycol to the alcohol (a) is preferably in a range of 1/100 to 5/1. It is preferable that one same compound is used as the alcohol (a) and the alcohol (b). In the case where the primary and secondary reactions are successively executed, a reaction device in which a primary reactor and a secondary reactor are connected in a two-stage connection type is preferably used. This ensures that a method is provided that is capable of producing &agr;-oxoaldehyde at a higher yield than conventionally, and further, that is capable of stably obtaining an &agr;-oxoaldehyde solution or gas with a higher concentration than conventionally.

Abstract: The present invention provides a process for producing an alkyl ether of a phenol from a phenol and an alcohol at a selectivity and a yield higher than in conventional processes, stably over a long period of time. The process is characterized by alkyl-etherifying a phenol with an alcohol in the presence of an oxide catalyst comprising an alkali metal as a constituent element.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: The present invention provides a novel process for producing an N-substituted aziridine compound by subjecting an N-substituted alkanolamine to a gas-phase catalytic dehydration reaction (the following reaction formula). ##STR1## In the above formula, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently one member of selected from a hydrogen atom and alkyl groups of 1-4 carbon atoms, and X is one member selected from alkyl groups of 1-4 carbon atoms, a cyclohexyl group, a phenyl group, a benzyl group, hydroxyalkyl groups of 1-4 carbon atoms and aminoalkyl groups of 1-4 carbon atoms.Preferably, the N-substituted aziridine compound is produced at a high yield by subjecting an N-substituted alkanolamine to a gas-phase catalytic dehydration reaction in the presence of a silicon-containing or phosphorus-containing catalyst under the conditions of reaction pressure=5-250 mmHg, reaction temperature=300.degree.-450.degree. C. and space velocity=50-500 hr.sup.-1 (STP).

Abstract: A method for regeneration of catalyst which comprises phosphorus and alkali metal element and/or alkaline earth metal element and was deteriorated by use to produce aziridine compound represented by the general formula ##STR1## wherein R is hydrogen, a methyl group or an ethyl group, by a catalytic vapor-phase intramolecular dehydration reaction of alkanolamine represented by the general formula ##STR2## wherein R is as defined in the formula (II), X is OH or NH.sub.2, and Y is either NH.sub.2 when X is OH or OH when X is NH.sub.2, characterized in that the deteriorated catalyst is contacted with gaseous volatile phosphorus compound.

Abstract: A process for producing a cyclic amine represented by the general formula ##STR1## wherein each of R and R' is selected from hydrogen, a methyl group and an ethyl group, and n is an integer of 2 to 5, which comprises vapor-phase intramolecular dehydration reaction of an alkanolamine represented by the general formula ##STR2## wherein R, R' and n are as defined above, said reaction being carried out in the presence of, as a catalyst, an oxide composition represented by the following formulaX.sub.a P.sub.b Y.sub.c O.sub.dwherein X is at least one element selected from transition metal elements of Groups I through VIII, lanthanide elements, actinide elements and elements of Group IIIA in the periodic table, Si, Ge, Sn, Pb, Sb and Bi, P is phosphorus, Y is at least one element selected from alkali metal elements and alkaline earth metal elements, O is oxygen, the suffixes a, b, c and d are the atomic ratios of the elements X, P, Y and O respectively, and when a=1, b=0.01-6, preferably 0.