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US 10,941,087 B2Granted
Process and plant for the adiabatic nitration of aromatic compounds
AssigneeJosef Meissner GmbH & Co. KG
InventorsJürgen Pöhlmann, Heinrich Hermann, Mirko Händel, Sophie Wernitz, Stefan Fankel
Life of this patent
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Abstract
The invention relates to a method for preferably adiabatic nitration of nitratable aromatic organic compounds (aromatics) and to a corresponding plant, in particular a production plant (nitration plant) for carrying out said method.
Claims14
A process for the adiabatic nitration of nitratable aromatic organic compounds for producing the corresponding nitrated aromatic organic compounds,
- wherein the nitratable aromatic organic compounds are converted, via a nitration reaction in the presence of a nitrating acid mixture comprising nitric acid and sulfuric acid, into the corresponding nitrated aromatic organic compounds,
- wherein the spent nitrating acid mixture resulting after the nitration reaction is recycled and circulated to the nitration reaction after the crude nitration aromatic organic compounds have been separated off and after subsequent concentration thereof;
- wherein the corresponding nitrated aromatic organic compounds are added to a reaction starting mixture, which reaction starting mixture comprises (i) the nitratable aromatic organic compounds to be nitrated and (ii) a nitrating acid mixture comprising nitric acid and sulfuric acid, and wherein the nitration reaction is started and carried out in the presence of the corresponding nitrated aromatic organic compounds;
- and
- wherein the nitrated aromatic organic compounds obtained are partly recirculated to the nitration reaction and the subsequent nitration reaction is started and carried out in the presence of said nitrated aromatic organic compounds;
- wherein the amount of corresponding nitrated aromatic organic compounds added to the nitration reaction is selected in such a way that the amount of added nitrated aromatic organic compounds effects lowering of the interfacial tension between organic phase and acid phase and effects an improved dispersibility of organic phase and acid phase, wherein the amount of nitrated aromatic organic compounds added to the nitration reaction is selected in such a way that the proportion by weight of added aromatic organic compounds, based on the sulfuric acid of the nitrating acid mixture comprising nitric acid and sulfuric acid, is in the range of from 0.02 to 10% by weight, and
- wherein the nitrated organic aromatic compounds added to the nitration reaction originate from the nitrated aromatic organic compounds obtained in the vapor condensate after concentration of the spent nitrating acid mixture;
- wherein the nitration reaction is carried out under adiabatic reaction conditions, and
- wherein the nitration reaction is carried out in a tube reactor.
6 more elements
A method for at least one of lowering the interfacial tension of an organic phase and an add phase and improving the dispersibility of an organic phase and an add phase in nitration reactions of nitratable aromatic organic compounds by the use of nitrated aromatic organic compounds,
- wherein the nitratable aromatic organic compounds are converted, via an adiabatic nitration reaction in the presence of a nitrating acid mixture comprising nitric acid and sulfuric acid, into the corresponding nitrated aromatic organic compounds;
- wherein the spent nitrating acid mixture resulting after the nitration reaction is recycled and circulated to the nitration reaction after the crude nitration aromatic organic compounds have been separated off and after subsequent concentration thereof;
- wherein the corresponding nitrated aromatic organic compounds are added to a reaction starting mixture, which reaction starting mixture comprises (i) the nitratable aromatic organic compounds to be nitrated and (ii) a nitrating acid mixture comprising nitric acid and sulfuric acid, and wherein the nitration reaction is started and carried out in the presence of the corresponding nitrated aromatic organic compounds;
- and
- wherein the nitrated aromatic organic compounds obtained are partly recirculated to the nitration reaction and the subsequent nitration reaction is started and carried out in the presence of said nitrated aromatic organic compounds;
- wherein the amount of corresponding nitrated aromatic organic compounds added to the nitration reaction is selected in such a way that the amount of added nitrated aromatic organic compounds effects lowering of the interfacial tension between organic phase and acid phase and effects an improved dispersibility of organic phase and acid phase, wherein the amount of nitrated aromatic organic compounds added to the nitration reaction is selected in such a way that the proportion by weight of added aromatic organic compounds, based on the sulfuric acid of the nitrating acid mixture comprising nitric acid and sulfuric acid, is in the range of from 0.02 to 10% by weight, and
- wherein the nitrated organic aromatic compounds added to the nitration reaction originate from the nitrated aromatic organic compounds obtained in the vapor condensate after concentration of the spent nitrating acid mixture;
- wherein the nitration reaction is carried out under adiabatic reaction conditions, and
- wherein the nitration reaction is carried out in a tube reactor.
6 more elements
A method for at least one of increasing the yields and reducing by-product formation and shortening the total reaction times and lowering the reaction start temperatures in nitration reactions of nitratable aromatic organic compounds by the use of nitrated aromatic organic compounds,
- wherein the nitratable aromatic organic compounds are converted, via an adiabatic nitration reaction in the presence of a nitrating acid mixture comprising nitric acid and sulfuric acid, into the corresponding nitrated aromatic organic compounds;
- wherein the spent nitrating acid mixture resulting after the nitration reaction is recycled and circulated to the nitration reaction after the crude nitration aromatic organic compounds have been separated off and after subsequent concentration thereof;
- wherein the corresponding nitrated aromatic organic compounds are added to a reaction starting mixture, which reaction starting mixture comprises (i) the nitratable aromatic organic compounds to be nitrated and (ii) a nitrating acid mixture comprising nitric add and sulfuric add, and wherein the nitration reaction is started and carried out in the presence of the corresponding nitrated aromatic organic compounds;
- and
- wherein the nitrated aromatic organic compounds obtained are partly recirculated to the nitration reaction and the subsequent nitration reaction is started and carried out in the presence of said nitrated aromatic organic compounds;
- wherein the amount of corresponding nitrated aromatic organic compounds added to the nitration reaction is selected in such a way that the amount of added nitrated aromatic organic compounds effects lowering of the interfacial tension between organic phase and acid phase and effects an improved dispersibility of organic phase and acid phase, wherein the amount of nitrated aromatic organic compounds added to the nitration reaction is selected in such a way that the proportion by weight of added aromatic organic compounds, based on the sulfuric acid of the nitrating acid mixture comprising nitric acid and sulfuric acid, is in the range of from 0.02 to 10% by weight, and
- wherein the nitrated organic aromatic compounds added to the nitration reaction originate from the nitrated aromatic organic compounds obtained in the vapor condensate after concentration of the spent nitrating acid mixture;
- wherein the nitration reaction is carried out under adiabatic reaction conditions, and
- wherein the nitration reaction is carried out in a tube reactor.
6 more elements
Dependencies are inferred from the claim text.