Abstract: The invention provides a process for preparing aromatic amines by catalytically hydrogenating the corresponding nitro compounds, especially for preparing tolylenediamine by hydrogenating dinitrotoluene, which comprises using hydrogenation catalysts in which the active component present is a mixture of platinum, nickel and an additional metal on a support.

Abstract: A process for preparing tolylenediamine by hydrogenating dinitrotoluene with hydrogen in the presence of a suspended catalyst in a vertically upright reactor (1), at the upper end of which is arranged a motive jet nozzle (2) through which the reaction mixture drawn off from the reactor bottom, via an external loop, is sprayed into the upper region of the reactor (1) and then flows into a central inserted tube (4) which is arranged in the longitudinal direction of the reactor, flows through the latter from the top downward and flows upward again outside the inserted tube (4) in an internal loop motion, with a heat exchanger (6) in the interior of the reactor (1), through which cooling water flows, and absorbs some of the heat of reaction as it does so, with a feed for the dinitrotoluene at the upper end of the reactor (1) and a feed for the hydrogen at the lower end of the reactor (1), and wherein, in addition to the heat exchanger (6) arranged in the interior of the reactor (1), a further heat exchanger (W

Abstract: The invention relates to a shell catalyst containing ruthenium as an active metal, alone or together with at least one other metal of the auxiliary group IB, VIIB or VIII of the periodical system of the elements (CAS version), and applied to a carrier containing silicon dioxide as a carrier material. The invention also relates to a method for producing said shell catalyst, and to a method for hydrogenating an organic compound containing hydrogenable groups, preferably for hydrogenating a carbocyclic aromatic group to form the corresponding carbocyclic aliphatic groups or for hydrogenating aldehydes to form the corresponding alcohols, using the inventive shell catalyst. The invention further relates to the use of the inventive shell catalyst for hydrogenating an organic compound containing hydrogenable groups, preferably for hydrogenating a carbocyclic aromatic group to form the corresponding carbocyclic aliphatic groups or for hydrogenating aldehydes to form the corresponding alcohols.

Abstract: A process for preparing 1,2-diamino-3-methylcyclohexane and/or 1,2-diamino-4-methylcyclohexane by reacting 2,3- and/or 3,4-diaminotoluene with hydrogen at elevated pressure and elevated temperature in the presence of a heterogeneous rhodium catalyst, wherein a mixture comprising 2,3- and/or 3,4-diaminotoluene, a dialkyl ether and/or alicyclic ether as a solvent and ammonia is initially charged in an autoclave in the presence of the catalyst and subsequently hydrogenated while supplying hydrogen.

Abstract: A process for preparing tolylenediamine by hydrogenating dinitrotoluene with hydrogen in the presence of a suspended catalyst in a vertically upright reactor (1), at the upper end of which is arranged a motive jet nozzle (2) through which the reaction mixture drawn off from the reactor bottom, via an external loop, is sprayed into the upper region of the reactor (1) and then flows into a central inserted tube (4) which is arranged in the longitudinal direction of the reactor, flows through the latter from the top downward and flows upward again outside the inserted tube (4) in an internal loop motion, with a heat exchanger (6) in the interior of the reactor (1), through which cooling water flows, and absorbs some of the heat of reaction as it does so, with a feed for the dinitrotoluene at the upper end of the reactor (1) and a feed for the hydrogen at the lower end of the reactor (1), and wherein, in addition to the heat exchanger (6) arranged in the interior of the reactor (1), a further heat exchanger (W

Abstract: Processes comprising: providing a starting material comprising one or more aromatic hydrocarbons, and having an aromatic sulfur compound content and a total sulfur content; reducing the aromatic sulfur compound content and the total sulfur content in the starting material; and hydrogenating the one or more aromatic hydrocarbons in the presence of a supported ruthenium catalyst and hydrogen.

Abstract: A process for aminating hydrocarbons with ammonia, wherein the N2 content in the mixture at the reactor exit is less than 0.1% by volume based on the total volume of the mixture at the reactor exit.

Abstract: A process for aminating hydrocarbons with ammonia in the presence of catalyst (i) which catalyzes the amination, which comprises supplying oxidizing agent to the reaction mixture and reacting the oxidizing agent with hydrogen which is formed in the amination in the presence of a catalyst (ii) which catalyzes this reaction with hydrogen.

Abstract: The invention relates to a shell catalyst containing ruthenium as an active metal, alone or together with at least one other metal of the auxiliary group IB, VIIB or VIII of the periodical system of the elements (CAS version), and applied to a carrier containing silicon dioxide as a carrier material. The invention also relates to a method for producing said shell catalyst, and to a method for hydrogenating an organic compound containing hydrogenable groups, preferably for hydrogenating a carbocyclic aromatic group to form the corresponding carbocyclic aliphatic groups or for hydrogenating aldehydes to form the corresponding alcohols, using the inventive shell catalyst. The invention further relates to the use of the inventive shell catalyst for hydrogenating an organic compound containing hydrogenable groups, preferably for hydrogenating a carbocyclic aromatic group to form the corresponding carbocyclic aliphatic groups or for hydrogenating aldehydes to form the corresponding alcohols.

Abstract: The invention relates to a process for preparing aromatic amines by hydrogenation of nitroaromatics in the presence of catalysts, in which a fluid reaction mixture which comprises amines and from which the catalysts are separated off is formed in a reactor. After the catalysts have been separated off, a measurement of the absorption of UV/VIS radiation by the reaction mixture is carried out to determine the concentration of nitro and nitroso compounds in the reaction mixture.

Abstract: A process for aminating hydrocarbons with ammonia, which comprises performing the amination in the presence of an additive which reacts with hydrogen, the additive used being at least one organic chemical compound, N2O, hydroxylamine, hydrazine and/or carbon monoxide.

Abstract: A process for preparing 1,2-diamino-3-methylcyclohexane and/or 1,2-diamino-4-methylcyclohexane by reacting 2,3- and/or 3,4-diaminotoluene with hydrogen at elevated pressure and elevated temperature in the presence of a heterogeneous rhodium catalyst, wherein a mixture comprising 2,3- and/or 3,4-diaminotoluene, a dialkyl ether and/or alicyclic ether as a solvent and ammonia is initially charged in an autoclave in the presence of the catalyst and subsequently hydrogenated while supplying hydrogen.

Abstract: The invention relates to a process for preparing aromatic amines by hydrogenation of nitroaromatics in the presence of catalysts, in which a fluid reaction mixture which comprises amines and from which the catalysts are separated off is formed in a reactor. After the catalysts have been separated off, a measurement of the absorption of UV/VIS radiation by the reaction mixture is carried out to determine the concentration of nitro and nitroso compounds in the reaction mixture.

Abstract: A process for aminating hydrocarbons comprises physically removing hydrogen from the reaction mixture.

Abstract: A process for aminating hydrocarbons with ammonia, wherein the N2 content in the mixture at the reactor exit is less than 0.1 % by volume based on the total volume of the mixture at the reactor exit.

Abstract: A process for aminating hydrocarbons with ammonia in the presence of catalyst (i) which catalyzes the amination, which comprises supplying oxidizing agent to the reaction mixture and reacting the oxidizing agent with hydrogen which is formed in the amination in the presence of a catalyst (ii) which catalyzes this reaction with hydrogen.

Abstract: The present invention provides a process for hydrogenating aromatic nitro compounds to the corresponding amines in the presence of hydrogenation catalysts, which comprises using hydrogenation catalysts in which nickel and platinum are present on a support in the form of an alloy having an atomic ratio of nickel to platinum in the alloy of between 30:70 and 70:30.

Abstract: Processes comprising: providing a starting material comprising one or more aromatic hydrocarbons, and having an aromatic sulfur compound content and a total sulfur content; reducing the aromatic sulfur compound content and the total sulfur content in the starting material; and hydrogenating the one or more aromatic hydrocarbons in the presence of a supported ruthenium catalyst and hydrogen.

Abstract: The present invention relates to a method for producing an aromatic hydrocarbon from a C1-C4-alkane, or a mixture of C1-C4-alkanes, which comprises a) bringing a feedstock stream A which comprises a C1-C4-alkane, or a mixture of C1-C4-alkanes, into contact with a catalyst and reacting a part of the C1-C4-alkane, or a part of the mixture of the C1-C4-alkanes, to form aromatic hydrocarbon(s); b) fractionating the product stream B resulting from step a) into a low-boiler stream C which comprises the majority of the hydrogen and of the unreacted C1-C4-alkane, or of the mixture of C1-C4-alkanes, and a high-boiler stream D, or a plurality of high-boiler streams D?, which stream or streams comprises or comprise the majority of the aromatic hydrocarbon formed; and c) feeding the low-boiler stream C to a further C1-C4-alkane-consuming method, if appropriate the hydrogen present in the low-boiler stream C being separated off in advance.

Abstract: The invention provides a process for preparing aromatic amines by catalytically hydrogenating the corresponding nitro compounds, especially for preparing tolylenediamine by hydrogenating dinitrotoluene, which comprises using hydrogenation catalysts in which the active component present is a mixture of platinum, nickel and an additional metal on a support.