Abstract: A process for continuously preparing the tert-butyl ester of an ethylenically unsaturated carboxylic acid, by a) reacting an ethylenically unsaturated carboxylic acid with isobutene in the presence of an acidic catalyst to give an esterification mixture; b) removing the acidic catalyst; c) removing low-boiling components; and d) supplying a tert-butyl ester-comprising liquid to a distillation apparatus and subjecting it to purifying distillation in the distillation apparatus, where d1) in the distillation apparatus the tert-butyl ester-comprising liquid is separated into a tert-butyl ester-comprising gaseous top product and a carboxylic acid-comprising liquid bottom product; d2) the tert-butyl ester-comprising gaseous top product is at least partly condensed and the condensate is recycled partly as reflux to the distillation apparatus; d3) the carboxylic acid-comprising liquid bottom product is recycled at least partly to step a); d4) carboxylic acid-comprising liquid bottom product is drawn off and passed to

Abstract: A process for continuously preparing the tert-butyl ester of an ethylenically unsaturated carboxylic acid, by a) reacting an ethylenically unsaturated carboxylic acid with isobutene in the presence of an acidic catalyst to give an esterification mixture; b) removing the acidic catalyst; c) removing low-boiling components; and d) supplying a tert-butyl ester-comprising liquid to a distillation apparatus and subjecting it to purifying distillation in the distillation apparatus, where d1) in the distillation apparatus the tert-butyl ester-comprising liquid is separated into a tert-butyl ester-comprising gaseous top product and a carboxylic acid-comprising liquid bottom product; d2) the tert-butyl ester-comprising gaseous top product is at least partly condensed and the condensate is recycled partly as reflux to the distillation apparatus; d3) the carboxylic acid-comprising liquid bottom product is recycled at least partly to step a); d4) carboxylic acid-comprising liquid bottom product is drawn off and passed to

Abstract: A process for continuously preparing the tert-butyl ester of an aliphatic C1-C4 carboxylic acid comprises: a) the reaction of an aliphatic C1-C4 carboxylic acid with isobutene in the presence of an acidic catalyst to give an esterification mixture (G1); b) the partial evaporation of the esterification mixture (G1), giving a liquid first high boiler phase (SPh1) comprising the acidic catalyst, and a first vapor (B1) comprising tert-butyl ester; c) the fractional condensation of the first vapor (B1) by partially condensing the first vapor (B1) at a first pressure and a first temperature and obtaining a first condensate (K1), partially condensing the uncondensed second vapor (B2) at a second pressure and a second temperature and obtaining a second condensate (K2), the first temperature being 0 to 45° C. below the condensation temperature of the tert-butyl ester at the first pressure and the second temperature being 45 to 80° C.

Abstract: A process for continuously preparing the tert-butyl ester of an aliphatic C1-C4 carboxylic acid comprises: a) the reaction of an aliphatic C1-C4 carboxylic acid with isobutene in the presence of an acidic catalyst to give an esterification mixture (G1); b) the partial evaporation of the esterification mixture (G1), giving a liquid first high boiler phase (SPh1) comprising the acidic catalyst, and a first vapor (B1) comprising tert-butyl ester; c) the fractional condensation of the first vapor (B1) by partially condensing the first vapor (B1) at a first pressure and a first temperature and obtaining a first condensate (K1), partially condensing the uncondensed second vapor (B2) at a second pressure and a second temperature and obtaining a second condensate (K2), the first temperature being 0 to 45° C. below the condensation temperature of the tert-butyl ester at the first pressure and the second temperature being 45 to 80° C.

Abstract: An eggshell catalyst consisting of a hollow cylindrical support body of length 2 to 10 mm, external diameter 4 to 10 mm and wall thickness 1 to 4 mm, and an eggshell, applied to the outer surface of the support body, of catalytically active oxide material of the general formula I, Mo12V2 to 4W0 to 3Cu0.8 to 1.5X10 to 4X20 to 40On??(I) in which the variables are each defined as follows: X1=one or more elements of the alkali metals and alkaline earth metals; X2=one or more elements from the group of Si, Al, Ti and Zr; and n=the stoichiometric coefficient of the element oxygen, which is determined by the stoichiometric coefficients of the elements other than oxygen and the charges thereof in I.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide of stoichiometry [Bi1WbOx]a[Mo12Z1cZ2dFeeZ3fZ4gZ5hOy]1, in which a finely divided oxide Bi1WbOx with the particle size d50A1 and, formed from element sources, a finely divided intimate mixture of stoichiometry Mo12Z1cZ2dFeeZ3fZ4gZ5h with the particle size d90A2 are mixed in a ratio of a:1, this mixture is used to form shaped bodies and these are treated thermally, where (d50A1)0.7·(d90A2)1.5·(a)?1?820. A shaped catalyst body obtained by the process. A catalyst obtained by grinding the shaped catalyst body. A process for heterogeneously catalyzing the partial gas phase oxidation of an alkane, alkanol, alkanal and/or an alkenal of 3 to 6 carbon atoms using the catalyst.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide of stoichiometry [Bi1WbOx]a[Mo12Z1cZ2dFeeZ3fZ4gZ5hOy]1, in which a finely divided oxide Bi1WbOx with the particle size d50A1 and, formed from element sources, a finely divided intimate mixture of stoichiometry Mo12Z1cZ2dFeeZ3fZ4gZ5h with the particle size d90A2 are mixed in a ratio of a:1, this mixture is used to form shaped bodies and these are treated thermally, where (d50A1)0.7·(d90A2)1.5·(a)?1?820. A shaped catalyst body obtained by the process. A catalyst obtained by grinding the shaped catalyst body. A process for heterogeneously catalyzing the partial gas phase oxidation of an alkane, alkanol, alkanal and/or an alkenal of 3 to 6 carbon atoms using the catalyst.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide of stoichiometry [Bi1WbOx]a[Mo12Z1cZ2dFeeZ3fZ4gZ5nOy]1, in which a finely divided oxide Bi1WbOx with the particle size d50A1 and, formed from element sources, a finely divided intimate mixture of stoichiometry Mo12Z1cZ2dFeeZ3fZ4gZ5h with the particle size d50A2 are mixed in a ratio of a:1, this mixture is used to form shaped bodies and these are treated thermally, where (d50A1)0.7·(d90A1)1.5·(a)?1?820.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide of stoichiometry [Bi1WbOx]a[Mo12Z1cZ2dFeeZ3fZ4gZ5hOy]1, in which a finely divided oxide Bi1WbOx with the particle size d50A1 and, formed from element sources, a finely divided intimate mixture of stoichiometry Mo12Z1cZ2dFeeZ3fZ4gZ5h with the particle size d90A2 are mixed in a ratio of a:1, this mixture is used to form shaped bodies and these are treated thermally, where (d50A1)0.7·(d90A2)1.5·(a)?1?820. A shaped catalyst body obtained by the process. A catalyst obtained by grinding the shaped catalyst body. A process for heterogeneously catalyzing the partial gas phase oxidation of an alkane, alkanol, alkanal and/or an alkenal of 3 to 6 carbon atoms using the catalyst.

Abstract: A process for preparing C1-C4-oxygenates from a reactant stream A which comprises essentially a C1-C4-alkane or a mixture of C1-C4-alkanes, by a) branching off a substream B of the reactant stream A and allowing it to react in a reactor with oxygen or an oxygenous gas stream C, which converts a portion of the C1-C4-alkane or a portion of the mixture which comprises C1-C4-alkanes to C1-C4-oxygenates, b) removing at least 90 mol % of the C1-C4-oxygenates formed from the product stream D resulting from step a) to form a remaining low boiler stream E, which comprises combining the low boiler stream E with the reactant stream A without further workup and without combination with the substream B down-stream of the branching site of the substream B.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide which comprises the element Mo, the elements Bi and/or V and one or more of the elements Co, Ni, Fe, Cu and alkali metals, in which sources of the different elements are used to obtain a finely divided mixture which is coarsened to a powder by press agglomeration, the coarsened powder is used to form, by press agglomeration, shaped bodies V which are separated into undamaged shaped bodies V+ and into damaged shaped bodies V?, the undamaged shaped bodies V+ are converted by thermal treatment to the shaped catalyst bodies K, and the damaged shaped bodies V? are comminuted and recycled into the obtaining of the finely divided mixture.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide which comprises the element Mo, the elements Bi and/or V and one or more of the elements Co, Ni, Fe, Cu and alkali metals, in which sources of the different elements are used to obtain a finely divided mixture which is coarsened to a powder by press agglomeration, the coarsened powder is used to form, by press agglomeration, shaped bodies V which are separated into undamaged shaped bodies V+ and into damaged shaped bodies V?, the undamaged shaped bodies V+ are converted by thermal treatment to the shaped catalyst bodies K, and the damaged shaped bodies V? are comminuted and recycled into the obtaining of the finely divided mixture.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide of stoichiometry [BiaZ1bOx]p[BicMo12FedZ2eZ3fZ4gZ5hZ6iOy]1, in which a finely divided oxide BiaZ1bOx and, formed from element sources, a finely divided mixture of stoichiometry BicMo12FedZ2eZ3fZ4gZ5hZ6i are mixed in a ratio of p:1, this mixture is used to form shaped bodies and these are treated thermally, where 0<c?0.8.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide which comprises the element Mo, the elements Bi and/or V and one or more of the elements Co, Ni, Fe, Cu and alkali metals, in which sources of the different elements are used to obtain a finely divided mixture which is coarsened to a powder by press agglomeration, the coarsened powder is used to form, by press agglomeration, shaped bodies V which are separated into undamaged shaped bodies V+ and into damaged shaped bodies V?, the undamaged shaped bodies V+ are converted by thermal treatment to the shaped catalyst bodies K, and the damaged shaped bodies V? are comminuted and recycled into the obtaining of the finely divided mixture.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide of stoichiometry [BiaZ1bOx]p[BicMo12FedZ2eZ3fZ4gZ5hZ6iOy]1, in which a finely divided oxide BiaZ1bOx and, formed from element sources, a finely divided mixture of stoichiometry BicMo12FedZ2eZ3fZ4gZ5hZ6i are mixed in a ratio of p:1, this mixture is used to form shaped bodies and these are treated thermally, where 0<c?0.8.

Abstract: A process for regenerating a catalyst bed deactivated in the course of a heterogeneously catalyzed partial dehydrogenation of a hydrocarbon, in which a gas comprising molecular oxygen is conducted at elevated temperature through the deactivated catalyst bed and, in the course of the regeneration, the content of molecular oxygen in the regeneration gas is increased repeatedly and the increase in the carbon oxide content of the regeneration gas as it flows through the deactivated catalyst bed is restricted to values of ?5% by volume.

Abstract: An eggshell catalyst consisting of a hollow cylindrical support body of length 2 to 10 mm, external diameter 4 to 10 mm and wall thickness 1 to 4 mm, and an eggshell, applied to the outer surface of the support body, of catalytically active oxide material of the general formula I, Mo12V2 to 4W0 to 3Cu0.8 to 1.5X10 to 4X20 to 40On??(I) in which the variables are each defined as follows: X1=one or more elements of the alkali metals and alkaline earth metals; X2=one or more elements from the group of Si, Al, Ti and Zr; and n=the stoichiometric coefficient of the element oxygen, which is determined by the stoichiometric coefficients of the elements other than oxygen and the charges thereof in I.

Abstract: A process for preparing C1-C4-oxygenates from a reactant stream A which comprises essentially a C1-C4-alkane or a mixture of C1-C4-alkanes, by a) branching off a substream B of the reactant stream A and allowing it to react in a reactor with oxygen or an oxygenous gas stream C, which converts a portion of the C1-C4-alkane or a portion of the mixture which comprises C1-C4-alkanes to C1-C4-oxygenates, b) removing at least 90 mol % of the C1-C4-oxygenates formed from the product stream D resulting from step a) to form a remaining low boiler stream E, which comprises combining the low boiler stream E with the reactant stream A without further workup and without combination with the substream B down-stream of the branching site of the substream B.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide which comprises the element Mo, the elements Bi and/or V and one or more of the elements Co, Ni, Fe, Cu and alkali metals, in which sources of the different elements are used to obtain a finely divided mixture which is coarsened to a powder by press agglomeration, the coarsened powder is used to form, by press agglomeration, shaped bodies V which are separated into undamaged shaped bodies V+ and into damaged shaped bodies V?, the undamaged shaped bodies V+ are converted by thermal treatment to the shaped catalyst bodies K, and the damaged shaped bodies V? are comminuted and recycled into the obtaining of the finely divided mixture.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide of stoichiometry [BiaZ1bOx]p[BicMo12FedZ2eZ3fZ4gZ5hZ6iOy]1, in which a finely divided oxide BiaZ1bOx and, formed from element sources, a finely divided mixture of stoichiometry BicMo12FedZ2eZ3fZ4gZ5hZ6i are mixed in a ratio of p:1, this mixture is used to form shaped bodies and these are treated thermally, where 0<c?0.8.