Abstract: Process for the preparation of N-vinylcarboxamides by pyrolysis of a compound of the formula CH3—CH(CN)—N(R)—CO—R1??(I), in which R and R1 are H or C1- to C6-alkyl, in the presence of solids which are doped with alkali metal or alkaline earth metal ions, under reduced pressure at a temperature of from 330 to 750° C. with elimination of hydrogen cyanide, cooling, separation and isolation of the reaction products, a solid arranged in a tubular reactor being treated at a temperature in the range from 0 to 250° C. with a solution of an alkali metal and/or alkaline earth metal base, the solution being discharged, the remaining solvent which adheres to the catalyst thus obtainable being evaporated and said catalyst then being heated to a temperature of at least 380° C. for activation.

Abstract: A process for the hydrolysis of polymers comprising vinylcarboxamide units by heating polymers comprising vinylcarboxamide units in an aqueous medium in the presence of acids or bases, wherein an aqueous solution or dispersion of a polymer comprising vinylcarboxamide units and an aqueous solution or a base or acid are fed continuously to a tubular reactor at elevated pressure, from 0.05 to less than one equivalent of a base or acid being used per vinylcarboxamide equivalent and the mixture being passed through the tubular reactor at a temperature of >100° C. to 250° C., depressurized and cooled.

Abstract: A process for removing carbonaceous deposits on surfaces of catalysts and plant parts by treating the deposits with a superheated stream of steam admixed at least temporarily with an oxygenous gas is provided, which involves, in each case monitoring the offgas CO2 content after condensation of the steam, at a temperature of at least 300° C.: (a) treating the carbonaceous deposits with superheated steam at a temperature of at least 300° C. until the CO2 content of the offgas has exceeded a maximum; (b) then, with further supply of superheated steam, commencing oxygen supply, the amount of oxygen supplied being adjusted such that the CO2 content in the offgas decreases further until it has fallen to a value of <1% by volume; and then (c) ending the supply of superheated steam and passing an oxygenous gas over remaining amounts of carbonaceous deposits until the deposits have been virtually removed.

Abstract: Process for the preparation of N-vinylcarboxamides by pyrolysis of a compound of the formula CH3—CH(CN)—N(R)—CO—R1 ??(I), in which R and R1 are H or C1- to C6-alkyl, in the presence of solids which are doped with alkali metal or alkaline earth metal ions, under reduced pressure at a temperature of from 330 to 750° C. with elimination of hydrogen cyanide, cooling, separation and isolation of the reaction products, a solid arranged in a tubular reactor being treated at a temperature in the range from 0 to 250° C. with a solution of an alkali metal and/or alkaline earth metal base, the solution being discharged, the remaining solvent which adheres to the catalyst thus obtainbale being evaporated and said catalyst then being heated to a temperature of at least 380° C. for activation.

Abstract: A process for the hydrolysis of polymers comprising vinylcarboxamide units by heating polymers comprising vinylcarboxamide units in an aqueous medium in the presence of acids or bases, wherein an aqueous solution or dispersion of a polymer comprising vinylcarboxamide units and an aqueous solution or a base or acid are fed continuously to a tubular reactor at elevated pressure, from 0.05 to less than one equivalent of a base or acid being used per vinylcarboxamide equivalent and the mixture being passed through the tubular reactor at a temperature of >100° C. to 250° C., depressurized and cooled.

Abstract: A process for removing carbonaceous deposits on surfaces of catalysts and plant parts by treating the deposits with a superheated stream of steam admixed at least temporarily with an oxygenous gas, which comprises, in each case with monitoring of the CO2 content in the offgas after condensation of the steam, at a temperature of at least 300° C., (a) treating the carbonaceous deposits with superheated steam at a temperature of at least 300° C. until the CO2 content of the offgas has exceeded a maximum, (b) then, with further supply of superheated steam, commencing the supply of oxygen, the amount of oxygen supplied being adjusted such that the CO2 content in the offgas decreases further until it has fallen to a value of <1% by volume, and then (c) ending the supply of superheated steam and passing an oxygenous gas over the amounts of carbonaceous deposits still remaining until the deposits have been virtually removed.

Abstract: The invention relates to a method for producing macrocyclic ketones of general formula (I) by direct cyclisation of compounds of general formula (II) in the gas phase on a heterogeneous catalyst. In general formula (I), X represents a monounsaturated or polyunsaturated or saturated C10–C17 alkyl radical which can be optionally substituted by a C1–C6 alkyl radical, and in general formula (II), R1, R2 can respectively be the same or different and represent hydrogen or C1–C6 alkyl, and has the above-mentioned designation.

Abstract: A process for the preparation of imidazo[1,2-a]-5,6,7,8-tetra hydropyridin-8-ones by reaction of ?-butyrolactones with imidazols, novel imidazo[1,2-a]-5,6,7,8-tetrahydropyridin-8-ones, and their use for the preparation of imidazo[1,2-a]pyridines are described.

Abstract: In a process for the catalytic hydrogenation of a polymethylolalkanal or a monomethylolalkanal of the formula (I) where R may be identical or different and are each a substituted or unsubstituted aliphatic hydrocarbon having from 1 to 22 carbon atoms, an aryl or arylalkyl group having from 6 to 22 carbon atoms or a methylol group, in the presence of a copper-containing catalyst, the hydrogenation feed comprising the polymethylolalkanal or monomethylolalkanal has a total content of metal ions of groups 3 to 14 of the Periodic Table of the Element of up to 5 ppm.

Abstract: The invention relates to a method for producing macrocyclic ketones of general formula (I) by direct cyclisation of compounds of general formula (II) in the gas phase on a heterogeneous catalyst. In general formula (I), X represents a monounsaturated or polyunsaturated or saturated C10-C17 alkyl radical which can be optionally substituted by a C1-C6 alkyl radical, and in general formula (II), R1, R2 can respectively be the same or different and represent hydrogen or C1-C6 alkyl, and has the above-mentioned designation.

Abstract: A method for producing unsaturated cyclic ethers of general formula (I) wherein Z represents (CHR4)q— or (CHR4)q—O—, q 0, 1, 2 or 3 and R1, R2, R3, R4 represent hydrogen or C1-C4-alkyl, by reacting dioles of general formula (II), wherein Z, R1, R2 and R3 have the above-mentioned meanings, in a liquid phase at temperatures of 150-300° C. in the presence of a support catalyst which is not activated prior to use by reduction and which contains cobalt and is doped with sulphur, containing cobalt, and an earth metal which is deposited by sol impregnation and is selected from the group containing platinum, palladium, rhodium, iridium, ruthenium, osmium, rhenium or mixtures thereof, on an inert support, characterized in that water is added.

Abstract: The invention relates to a method for catalytically hydrating a poly- or monomethylol alkanal of the general formula (I), wherein R is the same or different and may represent a substituted or unsubstituted aliphatic hydrocarbon with 6 to 22 carbon atoms, an aryl or arylalkyl group with 6 to 22 carbon atoms or a methylol group, in the presence of a copper-containing catalyst. The inventive method is characterized in that the poly- or monomethylol alkanal containing batch to be hydrated has a total content of up to 5 ppm of metal ions of the groups 3 to 14 of the periodic system.

Abstract: Polymethylolalkanoic or monomethylolalkanoic acids of the formula (I) 1

Abstract: Polymethylolalkanoic or monomethylolalkanoic acids of the formula (I) 1

Abstract: A process for isolating polymethylolalkanoic acids or monomethylolalkanoic acids of the formula (I) 1

Abstract: A process for preparing 3,4-dihydro-2H-pyran by reacting tetrahydrofurfuryl alcohol over solid oxidic catalysts at temperatures of from 150 to 400° C. and pressures of from 0.001 to 50 bar, which comprises carrying out the reaction in the gas phase in a tube bundle reactor.