Abstract: The present invention relates to a process for preparing an isocyanate, comprising hydrogenating a mixture (Gi) comprising an amine in the presence of a hydrogenation catalyst comprising copper to obtain a mixture (Gii) comprising the amine, and reacting the mixture (Gii) with phosgene to obtain a mixture (Giii) comprising the isocyanate. The present invention further relates to the isocyanate preparable by this process.

Abstract: The present invention relates to a process for the production of isocyanates, preferably diisocyanates and polyisocyanates of the diphenylmethane series (MDI), by reacting an amine with phosgene in the liquid phase or in the gas phase to form the corresponding isocyanates, subsequent removal of the solvent in at least two steps to obtain at least two solvent streams, individual treatment of the at least two solvent streams, and recirculation of at least a portion of the solvent streams.

Abstract: The invention relates to a method of measuring entry of water and resulting corrosion in plants for producing isocyanates by reacting phosgene with one or more primary amines in a solvent. The invention further relates to an apparatus for producing such isocyanates, in the work-up section of which probes for monitoring corrosion are arranged in defined places.

Abstract: The invention relates to a method of measuring entry of water and resulting corrosion in plants for producing isocyanates by reacting phosgene with one or more primary amines in a solvent. The invention further relates to an apparatus for producing such isocyanates, in the work-up section of which probes for monitoring corrosion are arranged in defined places.

Abstract: The present invention relates to a process for the production of isocyanates, preferably diisocyanates and polyisocyanates of the diphenylmethane series (MDI), by reacting an amine with phosgene in the liquid phase or in the gas phase to form the corresponding isocyanates, subsequent removal of the solvent in at least two steps to obtain at least two solvent streams, individual treatment of the at least two solvent streams, and re-circulation of at least a portion of the solvent streams.

Abstract: The present invention relates to a process for preparing an isocyanate, comprising hydrogenating a mixture (Gi) comprising an amine in the presence of a hydrogenation catalyst comprising copper to obtain a mixture (Gii) comprising the amine, and reacting the mixture (Gii) with phosgene to obtain a mixture (Giii) comprising the isocyanate. The present invention further relates to the isocyanate preparable by this process.

Abstract: A biodiesel fuel mixture having a cetane number of >40, comprising a) from 1 to 100% by weight of biodiesel, b) from 0 to 98.9% by weight of diesel oil of fossil origin, c) from 0.1 to 20% by weight of polyoxyalkylene dialkyl ether of the formula RO(CH2O)nR ?in which R is an alkyl group having from 1 to 10 carbon atoms and n=from 2 to 10, and d) from 0 to 5% by weight of further additives.

Abstract: The invention relates to a process for the prepartaion of alkanesulfonic acids, comprising the following steps: (a) oxidation of alkylmercaptans and/or dialkyl disulfides and/or dialkyl polysulfides having from three to nine sulfur atoms with nitric acid to form alkanesulfonic acids, water, nitrogen oxides and other byproducts, (b) regeneration of the nitrogen oxides obtained from step (a) with oxygen to give nitric acid and recycling of the nitric acid to step (a), where steps (a) and (b) are carried out in reaction chambers separate from one another.

Abstract: A process for preparing alkanesulfonic acids from dialkyl sulfites comprises the following steps: rearrangement of dialkyl sulfite in the presence of a suitable catalyst to form the corresponding alkyl alkanesulfonate and hydrolysis of the resulting alkyl alkanesulfonate to give the corresponding alkanesulfonic acid.

Abstract: A process for preparing lactams by hydrolytic cyclization of aminonitriles in the gas phase in the presence of a metal phosphate catalyst comprises using a catalyst comprising one or more oligophosphates of the general formula (I) M (POa)b  (I) where M is a metal of group 3 or 4 of the periodic table, including the lanthanides, a is >2.5 and <4.0, and b is such that electrical neutrality is ensured, or a mixture of one or more oligophosphates of the general formula (I) with one or more further salts of a metal of group 3 or 4 of the periodic table, including the lanthanides, with an inorganic acid.

Abstract: Aromatic hydrocarbons are nitrated by a process in which the aromatic hydrocarbon is reacted in the liquid phase with an oxide of nitrogen selected from NO, N2O3, NO2 and N2O4 and with an oxygen-containing gas stream in the presence of a heterogeneous oxidic catalyst, wherein at least 0.1 mol %, based on the aromatic hydrocarbon, of water is present at the beginning of the reaction.

Abstract: Aromatic hydrocarbons are nitrated by a process in which the aromatic hydrocarbon is reacted in the liquid phase with an oxide of nitrogen selected from NO, N2O3, NO2 and N2O4 and with an oxygen-containing gas stream in the presence of a heterogeneous oxidic catalyst, wherein at least 0.1 mol %, based on the aromatic hydrocarbon, of water is present at the beginning of the reaction.

Abstract: The invention relates to a process for preparing lactams by cyclizing hydrolysis of amino nitriles with water in the gas phase on catalysts which comprise oxides or mixed oxides of the metals of groups 3, 4, 5, 13 and/or 14 of the Periodic Table, where appropriate in addition a metal oxide of groups 6, 7, 8, 9 and/or 10, and further comprise a phosphate, carbonate, silicate, arsenite, arsenate, antimonite, antimonate and/or nitrate of said metals and/or, if metal oxides of groups 6, 7, 8, 9 or 10 are present, a sulfate of the abovementioned metals.

Abstract: A process for preparing methanesulfonic acid by irradiating a mixture comprising acetic acid, sulfur dioxide and oxygen with light, wherein the reaction mixture is irradiated with an average cumulative irradiance in the range from 240 to 320 mm of from 0.05 to 50 mmol quanta/cm2h at the light entry area.

Abstract: The present invention relates to a process for preparing 2-cyclo-alkenones of the formula I ##STR1## which comprises subjecting a 2-alkoxycycloalkanone and/or a 2-hydroxyalkanone ketal, in which n is an integer from 0 to 20, m is 0, 1, 2 or 3 and R is alkyl, alkylaryl, aryl, arylalkyl, alkenyl or alkynyl, to an elimination reaction in the gas phase on an acidic heterogeneous catalyst.

Abstract: In a process for preparing N-alkenylcarboxamides by dehydration of N-(2-hydroxyalkyl)carboxamides and/or diethers thereof in the presence of a catalyst, molecular sieves, in particular zeolites, are used as catalyst.

Abstract: Alkyl bromides are prepared from mixtures comprising aqueous hydrobromic acid and olefins in a process in which there is concentration of the aqueous hydrobromic acid present during the reaction.

Abstract: A process for preparing alkyl 5-oxo-6-heptenoates of the formula I ##STR1## where X and Y are hydrogen or methyl, and R.sup.1 is C.sub.1 -C.sub.8 -alkyl, byA) reacting 5-acetyl-2-norbornene with a dialkyl carbonate [CO(OR.sup.2).sub.2, where R.sup.2 is C.sub.1 -C.sub.4 -alkyl,] in the presence of a base to give an alkyl 3-(2-norbornen-5-yl)-3-oxopropionate II,B) reacting the ester II on the presence of a base with an unsaturated compound of the formula III ##STR2## where Z is CN or CO.sub.2 R.sup.3, where R.sup.3 is C.sub.1 -C.sub.4 -alkyl, and hydrolyzing the product of the reaction of compound II with compound III to a 5-(2-norbornen-5-yl)-5-oxopentanoic acid of the formula IV,C) esterifying the acid IV to give a 5-(2-norbornen-5-yl)-5-oxopentanoic ester of the formula V, andD) converting the ester V by thermal cleavage into an alkyl 5-oxo-6-heptenoate I.