Single Methyl And Plural Nitros Only Bonded Directly To Benzene Ring (e.g., Dinitrotoluene, Etc.) Patents (Class 568/934)
  • Patent number: 11231727
    Abstract: A method for continuously producing a product (A1) by way of at least two coupled-together chemical reactions (C1, C2), wherein at least two input substances (E1, E2) are fed to a first chemical reaction (C1), wherein a plurality of intermediate substances (Z1, Z2) are produced from the input substances (E1, E2) by the first chemical reaction (C1), wherein at least one of the intermediate substances (Z2) is fed to a second chemical reaction (C2), wherein the at least one fed intermediate substance (Z2) is further processed by the second chemical reaction (C2), in particular using at least one further substance (W1, W2) in a second chemical reaction (C2) to form a plurality of output substances (A1, A2), that is to say to form the chemical product (A1) and at least one further output substance (A2), wherein the flow rates (Fi) of the fed substances (E1, E2, Z1, W1, W2, A2) that are fed to one of the reactions (C1, C2) are set by a respective actuating element (VE1, VE2, VW1, VW 2, VZ 2, VA1), wherein each of t
    Type: Grant
    Filed: May 20, 2020
    Date of Patent: January 25, 2022
    Assignee: Covestro Deutschland AG
    Inventors: Bernd Pennemann, Erwin Dieterich, Heinz-Josef Hamacher
  • Patent number: 10698424
    Abstract: A method for continuously producing a product (A1) by way of at least two coupled-together chemical reactions (C1, C2), wherein at least two input substances (E1, E2) are fed to a first chemical reaction (C1), wherein a plurality of intermediate substances (Z1, Z2) are produced from the input substances (E1, E2) by the first chemical reaction (C1), wherein at least one of the intermediate substances (Z2) is fed to a second chemical reaction (C2), wherein the at least one fed intermediate substance (Z2) is further processed by the second chemical reaction (C2), in particular using at least one further substance (W1, W2) in a second chemical reaction (C2) to form a plurality of output substances (A1, A2), that is to say to form the chemical product (A1) and at least one further output substance (A2), wherein the flow rates (Fi) of the fed substances (E1, E2, Z1, W1, W2, A2) that are fed to one of the reactions (C1, C2) are set by a respective actuating element (VE1, VE2, VW1, VW 2, VZ 2, VA1), wherein each of t
    Type: Grant
    Filed: November 17, 2015
    Date of Patent: June 30, 2020
    Assignee: Covestro Deutschland AG
    Inventors: Bernd Pennemann, Erwin Dieterich, Heinz-Josef Hamacher
  • Patent number: 9630866
    Abstract: The present invention relates to a process for workup of nitrite-comprising alkaline process wastewaters from the nitration of aromatic compounds, wherein the alkaline process wastewater is acidified by addition of acids and the offgas which comprises nitrogen oxides and escapes from the acidified process wastewater is worked up, comprising the steps of a) acidifying the process wastewater by adding acid to a pH below 5, which forms an organic phase which separates out, an acidic aqueous phase and a gaseous NOx-containing phase, and b) removing the gaseous NOx-containing phase.
    Type: Grant
    Filed: December 13, 2010
    Date of Patent: April 25, 2017
    Assignee: BASF SE
    Inventors: Ruediger Fritz, Renate Hempel, Michael Zoellinger, Holger Allardt, Reiner Reetz
  • Patent number: 9428441
    Abstract: A process for the preparation of dintrotoluene which comprises (a) nitrating toluene with a nitrating acid, wherein said nitrating acid is a mixture of nitric acid and sulfuric acid, in one or more nitration steps, and separating the nitrating acid from the process stream thus formed, wherein a crude mixture comprising dinitrotoluene and a fraction of said nitrating acid dissolved therein is obtained, said crude mixture further comprising at least 50 ppm of HCN, and (b) washing the crude dinitrotoluene containing mixture in one or more washing steps, wherein, before the first washing step is carried out, the crude mixture is distilled and/or stripped to remove HCN therefrom, wherein a crude dinitrotoluene containing mixture which is essentially free of HCN is obtained.
    Type: Grant
    Filed: September 1, 2014
    Date of Patent: August 30, 2016
    Assignee: BASF SE
    Inventors: Yuan Shen Dai, Katharina Spuhl, Renate Hempel
  • Patent number: 9284257
    Abstract: Proposed is a separation method in a toluene to dinitrotoluene process, wherein said method with a first process step comprising feeding a toluene comprising first stream (1) and a nitric acid comprising second stream (2) into a first reactor (R1), reacting of the toluene comprising first stream (1) and the nitric acid comprising second stream (2) within the first reactor (R1) to a first reaction mixture (3), said first reaction mixture (3) comprising a first liquid/liquid mixed phase of an acid phase and an organic phase comprising mononitrotoluene, feeding the first reaction mixture (3) into a first separation device (S1), separating the first reaction mixture (3) within the first separation device (S1) into a first forward stream (4) having a flow direction to a second process step and a first backward stream (5) having a flow direction back to the first reactor (R1), said method having a second process step comprising feeding the first forward stream (4) into a second reactor (R2), feeding a nitric acid c
    Type: Grant
    Filed: December 10, 2013
    Date of Patent: March 15, 2016
    Assignees: BASF SE, Shanghai BASF Polyurethane Company Limited
    Inventors: Yuanshen Dai, Da Peng Li, Pei Shi Jia, Zhan Cai, Samuel Neto
  • Patent number: 9260377
    Abstract: The invention provides a continuous adiabatic process for the preparation of nitrobenzene by nitrating benzene with mixtures of sulfuric and nitric acids using a stoichiometric excess of benzene, wherein the content of organic compounds in the circulating sulfuric acid, at least during the start-up period of the production plant, is always kept below 1.0 mass percent, based on the total mass of circulating sulfuric acid. This is preferably achieved by a procedure in which, either after the end or before the beginning of a production cycle, the circulating sulfuric acid is circulated at elevated temperature so that the organics contained in the sulfuric acid, preferably comprising nitrobenzene and traces of benzene, dinitrobenzene and nitrophenols, are separated off in the evaporation apparatus for concentrating the sulfuric acid.
    Type: Grant
    Filed: July 23, 2013
    Date of Patent: February 16, 2016
    Assignee: Bayer MaterialScience AG
    Inventors: Thomas Knauf, Michael Merkel, Antoni Mairata
  • Patent number: 9115048
    Abstract: The present invention relates to a method for removing impurities from nitrated crude products obtained during the nitration of nitratable aromatic compounds, after removal of the final nitrating acid, by treatment with a washing medium, and also to a plant or apparatus suitable for implementing this method. Further provided by the invention is a production plant for the nitration of nitratable aromatic compounds with subsequent purification of the nitrated products.
    Type: Grant
    Filed: May 18, 2012
    Date of Patent: August 25, 2015
    Assignee: Josef Meissner GmbH & Co. KG
    Inventors: Jürgen Pöhlmann, Heinrich Hermann, Mirko Handel, Jurgen Gebauer
  • Patent number: 9108847
    Abstract: A method for reprocessing waste acid from methods for producing nitro-aromatics, in particular for producing dinitrotoluene (DNT) or trinitrotoluene (TNT), to recover concentrated and purified sulfuric acid and nitric acid, wherein in a first stage, the waste acid is separated in a stripping column countercurrently with water vapor from the bottom of the stripping column into at least one vapor phase, which contains nitric acid and possibly nitro-organics, and a pre-concentrated sulfuric acid, and the vapor phase and the pre-concentrated sulfuric acid are condensed and/or reprocessed in downstream method stages, wherein in the first stage of the method, in addition to the stripping, the nitric acid contained in the stripping vapor is concentrated in the presence of additional concentrated sulfuric acid so that nitric acid in a highly concentrated form suitable for feeding back into the nitration process is obtained directly in the first stage.
    Type: Grant
    Filed: September 8, 2010
    Date of Patent: August 18, 2015
    Assignee: DE Dietrich Process Systems GMBH
    Inventors: Gottfried Dichtl, Harald Steeg
  • Publication number: 20140039227
    Abstract: The invention relates to a process for scrubbing a crude mixture comprising dinitrotoluene, nitric acid, nitrogen oxides and sulfuric acid obtained in the nitration of toluene after the nitrating acid has been separated off, which comprises two scrubbing steps (SS-I) and (SS-II), wherein i) in a first scrubbing step (SS-I), the crude mixture is extracted with a scrubbing acid I comprising nitric acid, nitrogen oxides and sulfuric acid in a scrub comprising at least one extraction stage, where the scrubbing acid discharged from the first extraction stage (SS-I-1) of the first scrubbing step (SS-I) has a total acid content of from 20 to 40% by weight and a prescrubbed crude mixture is obtained, ii) in a second scrubbing step (SS-II), the prescrubbed crude mixture comprising dinitrotoluene is extracted with a scrubbing acid II in a scrub comprising at least one extraction stage, where the scrubbing acid discharged from the first extraction stage (SS-II-1) of the second scrubbing step (SS-II) has a pH of less
    Type: Application
    Filed: April 25, 2013
    Publication date: February 6, 2014
    Inventor: BASF SE
  • Patent number: 8410322
    Abstract: The present invention relates to a process for preparing dinitrotoluene. The process of the invention for preparing dinitrotoluene from mononitrotoluene, which comprises carrying out a mononitrotoluene nitration reaction using a nitrating mixture comprising nitric acid, sulphuric acid and water resulting in a two-phase medium and separating the organic and aqueous phases of said two-phase medium, is characterized in that the mononitrotoluene nitration is carried out using a nitrating mixture comprising at most 10% by weight of water resulting in a two-phase medium, in that the organic and aqueous phases of said two-phase medium are separated, and in that the aqueous phase derived from the separating operation is recycled, at the end of the mononitrotoluene nitration reaction and before the separation of the organic and aqueous phases, such that the weight ratio of the aqueous phase to the organic phase is at least equal to 1.2.
    Type: Grant
    Filed: July 8, 2008
    Date of Patent: April 2, 2013
    Assignee: Vencorex France
    Inventor: Philippe Marion
  • Publication number: 20120136181
    Abstract: A method of removing alkalinity and salt from a nitroaromatic product downstream of water washing to remove mineral acids and alkaline washing to remove salts of organic acids, comprises washing the product stream with an acidic aqueous solution, prior to the step of removing excess organic reactant, by steam stripping or distillation. Acid removed from the stripper or column is recycled back for use in the acidic washing. The acidic washing is done instead of the neutral washing step of the prior art. It removes residual salt and decreases the level of entrained colloidal water in the nitroaromatic product.
    Type: Application
    Filed: August 18, 2009
    Publication date: May 31, 2012
    Applicant: NORAM INTERNATIONAL LIMITED
    Inventor: Sergio Berretia
  • Patent number: 7928270
    Abstract: A process is proposed for distillatively removing dinitrotoluene from process wastewater from the preparation of dinitrotoluene by nitrating toluene with nitrating acid, which comprises basifying the process wastewater to a pH of >8.5, feeding it to a stripping column in the upper region thereof and stripping it with steam in countercurrent to obtain a vapor stream laden with dinitrotoluene and a bottom stream depleted in dinitrotoluene compared to the process wastewater used.
    Type: Grant
    Filed: March 6, 2007
    Date of Patent: April 19, 2011
    Assignee: BASF Aktiengesellschaft
    Inventors: Ulrich Penzel, Ruediger Fritz, Holger Allardt, Johannes Adam, Anne-Kathrin Merten
  • Patent number: 7851661
    Abstract: The present invention provides a process for preparing dinitrotoluene, comprising the steps of a) reacting toluene with nitric acid in the presence of sulphuric acid to give mononitrotoluene, b) separating the reaction product from step a) into an organic phase comprising mononitrotoluene and an aqueous phase comprising sulfuric acid, c) reacting the organic phase comprising mononitrotoluene with nitric acid in the presence of sulphuric acid to give dinitrotoluene, d) separating the reaction product from step c) into an organic phase comprising dinitrotoluene and an aqueous phase comprising sulfuric acid, wherein the reaction product from step a) has a content of toluene of from 3.0 to 8% by weight, based on the organic phase, and a content of nitric acid of from 0.1 to 1.2% by weight, based on the aqueous phase, and the phase separation in step b) is effected in such a way that further reaction of the toluene with the nitric acid is prevented.
    Type: Grant
    Filed: February 2, 2005
    Date of Patent: December 14, 2010
    Assignee: BASF Aktiengesellschaft
    Inventors: Johannes Buettner, Wolfgang Mackenroth, Heinrich Hermann, Peter Konieczny, Juergen Gebauer
  • Publication number: 20100185026
    Abstract: Nitro-compounds are hydrogenated with an activated Ni catalyst whose Ni/Al alloy also contained one or more elements from the list of Cu, Ag and Au prior to activation. In combination with the Group IB elements mentioned above, this catalyst can also be doped with other elements via their addition to the Ni/Al alloy prior to activation and/or they can be adsorbed onto the surface of the catalyst either during or after the activation of the alloy. The suitable doping elements for the alloy prior to activation in combination with the group IB elements mentioned above are one or more of the elements from the list of Mg, Ti, Ce, Cr, V, Mo, W, Mn, Re, Fe, Co, Tr, Ru, Rh, Pd, Pt and Bi. The suitable doping elements that may be adsorbed onto the surface of the catalyst that was previously doped in the alloy prior to activation with the group IB elements mentioned above are one or more elements from the list Mg, Ca, Ba, Ti, Ce, V, Cr, Mo, W, Mn, Re, Fe, Ru, Co, Rh, Ir, Pd, Pt, Ni, Cu, Ag, Au and Bi.
    Type: Application
    Filed: May 29, 2007
    Publication date: July 22, 2010
    Applicant: EVONIK DEGUSSA GMBH
    Inventors: Daniel Ostgard, Monika Berweiler, Markus Gottlinger, Steffen Laporte, Matthias Schwarz
  • Publication number: 20100145109
    Abstract: The present invention relates to a process for preparing dinitrotoluene. The process of the invention for preparing dinitrotoluene from mononitrotoluene, which comprises carrying out a mononitrotoluene nitration reaction using a nitrating mixture comprising nitric acid, sulphuric acid and water resulting in a two-phase medium and separating the organic and aqueous phases of said two-phase medium, is characterized in that the mononitrotoluene nitration is carried out using a nitrating mixture comprising at most 10% by weight of water resulting in a two-phase medium, in that the organic and aqueous phases of said two-phase medium are separated, and in that the aqueous phase derived from the separating operation is recycled, at the end of the mononitrotoluene nitration reaction and before the separation of the organic and aqueous phases, such that the weight ratio of the aqueous phase to the organic phase is at least equal to 1.2.
    Type: Application
    Filed: July 8, 2008
    Publication date: June 10, 2010
    Applicant: PERSTORP FRANCE
    Inventor: Philippe Marion
  • Publication number: 20100130796
    Abstract: Improved micro machined (MEMs scale) heaters, which are particularly suitable for use in MEMs scale preconcentrators. Preferably the heater possess a trapping medium, in particular a polymer of intrinsic microporosity (PIMs). There is further provided devices comprising the preconcentrator, and methods of preparation and use. There is particular benefit directed to the use of a MEMs scale heater coated with the PIMs for use in hand-held or field portable chemical detection devices. The heater comprises a number of electrically conducting paths which have been engineered so that the electrical resistance of all the electrically conducting paths are substantially equal, to provide a more uniform heat distribution.
    Type: Application
    Filed: June 25, 2008
    Publication date: May 27, 2010
    Inventors: David J. Combes, Tomothy I. Cox, Ian C. Sage
  • Patent number: 7511176
    Abstract: The present invention relates to a process for the preparation of toluenediamine, in which dinitrotoluene is reacted with hydrogen in the presence of a catalyst. The dinitrotoluene required by this process has a content of carbon dioxide, in either physically dissolved or chemically bonded form, of not more than 0.175 mol %, based on the molar amount of the dinitrotoluene.
    Type: Grant
    Filed: December 13, 2007
    Date of Patent: March 31, 2009
    Assignee: Bayer MaterialScience AG
    Inventors: Fritz Pohl, Wolfgang Lorenz, Lars Padeken, Bernd Pennemann, Friedhelm Steffens, Gerhard Wiechers
  • Patent number: 7495136
    Abstract: Dinitrotoluene is produced by nitration of toluene with nitrating acid (mixture of nitric acid and sulfuric acid) in which, in a first stage, the toluene is converted to mononitrotoluene (MNT) and then the mononitrotoluene is converted in a second stage to dinitrotoluene (DNT). Control of the weight ratio of the aqueous to organic phases, dispersion of the organic phase in the aqueous phase and use of less than 2.06 moles of nitric acid per mole of toluene are key features of this process.
    Type: Grant
    Filed: July 12, 2007
    Date of Patent: February 24, 2009
    Assignee: Bayer MaterialScience AG
    Inventors: Fritz Pohl, Wolfgang Lorenz, Juergen Muennig, Bernd Pennemann, Gerhard Wiechers
  • Publication number: 20090043135
    Abstract: A process is proposed for distillatively removing dinitrotoluene from process wastewater from the preparation of dinitrotoluene by nitrating toluene with nitrating acid, which comprises basifying the process wastewater to a pH of >8.5, feeding it to a stripping column in the upper region thereof and stripping it with steam in countercurrent to obtain a vapor stream laden with dinitrotoluene and a bottom stream depleted in dinitrotoluene compared to the process wastewater used.
    Type: Application
    Filed: March 6, 2007
    Publication date: February 12, 2009
    Applicant: BASF SE
    Inventors: Ulrich Penzel, Rudiger Fritz, Holger Allardt, Johannes Adam, Anne-Kathrin Merten
  • Patent number: 7449610
    Abstract: The invention provides a process for removing nitrocresols from wastewater of mononitrotoluene preparation, which comprises acidifying the alkaline wastewater of mononitrotoluene preparation with acids to a pH of at most 3 and treating the nitrocresols with an extractant. The invention further provides the preparation of dinitrotoluene by use of the nitrocresol-containing extracts as a feedstock.
    Type: Grant
    Filed: September 18, 2004
    Date of Patent: November 11, 2008
    Assignee: BASF SE
    Inventors: Johannes Buettner, Holger Allardt, Reinhard Tonder, Reiner Reetz, Michael Reichelt
  • Patent number: 7435319
    Abstract: The invention relates to a semibatchwise process for the mild distillative separation of mixtures, in a first stage a column being supplied continuously with a feed and the feed being separated at least into different fractions, one of the fractions being removed continuously into a container, and, in a second step, the fraction removed into the container being recycled to the column and being separated again batchwise into different fractions.
    Type: Grant
    Filed: May 12, 2003
    Date of Patent: October 14, 2008
    Assignee: LANXESS Deutschland GmbH
    Inventors: Ludwig Deibele, Dieter Heinz, Jan Thomas Leu, Johannes-Peter Schäfer, Kai Fahrenkamp, Wolfgang Scheinert, Thomas Schilling, Paul Wagner
  • Publication number: 20080242900
    Abstract: The invention relates to a method for producing dinitrotoluene, comprising the steps of a) reacting toluene with nitric acid in the presence of sulphuric acid to give mononitrotoluene, b) separating the reaction product of step a) into a mononitrotoluene-containing organic phase and a sulphuric acid-containing aqueous phase, c) reacting the mononitrotoluene-containing organic phase with nitric acid in the presence of sulphuric acid to give dinitrotoluene, d) separating the reaction product of step c) into a dinitrotoluene-containing organic phase and a sulphuric-acid containing aqueous phase, whereby the reaction product of step a) contains 3.0 to 8 wt % of toluene, in relation to the organic phase, and 0.1 to 1.2 wt. % of nitric acid, in relation to the aqueous phase and the phase separation of step b) is carried out in such a manner that further reaction of toluene with nitric acid is prevented.
    Type: Application
    Filed: February 2, 2005
    Publication date: October 2, 2008
    Applicant: BASF Aktiengesellschaft
    Inventors: Johannes Buttner, Wolfgang Mackenroth, Heinrich Hermann, Peter Konieczny, Jurgen Gebauer
  • Patent number: 7271300
    Abstract: An environmentally friendly picric acid explosive comprising, providing a nitromalondialdehyde, providing a dinitroketone, reacting the nitromalondialdehydes with the dinitroketone to produce a mixture, and subjecting the mixture to a cyclodehydrative mechanism to produce environmentally friendly picric acid explosive. Embodiments of the present invention include the picric acid explosive produced by the methods of described above.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: September 18, 2007
    Assignee: United States of America as represented by the Secretary of the Navy
    Inventor: Matthew C. Davis
  • Patent number: 6984762
    Abstract: The invention relates to a process for the production of dinitrotoluene by the two-stage nitration of toluene. In the first stage of this process, toluene was reacted adiabatically with nitrating acid so that at least 90% of the toluene was reacted off and no more than 70% of the toluene formed dinitrotoluene. The resulting organic phase containing mononitrotoluene and the aqueous acid phase containing sulfuric acid were separated, and the aqueous acid phase containing sulfuric acid was concentrated by flash evaporation. The resulting concentrated sulfuric acid was recycled into the reaction in the first stage, and/or into the reaction in the second stage, and/or into the concentration in the second stage. In the second stage, the organic phase containing mononitrotoluene from the first stage was completely reacted isothermally with nitrating acid.
    Type: Grant
    Filed: February 17, 2004
    Date of Patent: January 10, 2006
    Assignee: Bayer Aktiengesellschaft
    Inventors: Erwin Dieterich, Anke Hielscher, Berthold Keggenhoff, Manfred Keller-Killewald, Jürgen Münnig, Dietmar Wastian
  • Patent number: 6953869
    Abstract: The present invention relates to a process for working up organic secondary components which are formed in the one-stage or two-stage nitration of toluene to dinitrotoluene. These organic secondary components are present in the acidic and alkaline waste water from the dinitrotoluene washing step and in the aqueous distillate from the sulfuric acid concentration step, together with small amounts of mononitrotoluene and dinitrotoluene. This process comprises a) combining the acidic and alkaline waste waters from the washing step and the aqueous distillate from the sulfuric acid concentration step such that the resulting mixture has a pH below 5, b) separating the aqueous and organic phases which form by phase separation, and c) recycling the organic phase from step b) into the nitration process.
    Type: Grant
    Filed: June 28, 2004
    Date of Patent: October 11, 2005
    Assignee: Bayer MaterialScience AG
    Inventors: Jürgen Münnig, Dietmar Wastian, Wolfgang Lorenz, Berthold Keggenhoff
  • Patent number: 6936741
    Abstract: The present invention relates to a process for working up or treating aqueous waste waters which are formed during the nitration of toluene to dinitrotoluene with nitrating acid. These aqueous waste waters containing acidic wash water and alkaline wash water from the dinitrotoluene washing step, and distillate from the sulfuric acid concentration step. The process comprises, a) combining the acidic and alkaline waste waters from the washing step and the aqueous distillate from the sulfuric acid concentration step such that the resulting mixture has a pH below 5, b) separating the aqueous and organic phases which are formed by phase separation, c) subjecting the aqueous phase from b) to an extraction step, wherein d) the organic components contained in the aqueous phase from c) are extracted with toluene, and e) introducing the toluene phase enriched with the organic components into the toluene nitration.
    Type: Grant
    Filed: June 28, 2004
    Date of Patent: August 30, 2005
    Assignee: Bayer MaterialScience AG
    Inventors: Jürgen Münnig, Dietmar Wastian, Wolfgang Lorenz, Berthold Keggenhoff
  • Publication number: 20040262238
    Abstract: The present invention relates to a process for working up or treating aqueous waste waters which are formed during the nitration of toluene to dinitrotoluene with nitrating acid. These aqueous waste waters containing acidic wash water and alkaline wash water from the dinitrotoluene washing step, and distillate from the sulfuric acid concentration step.
    Type: Application
    Filed: June 28, 2004
    Publication date: December 30, 2004
    Inventors: Jurgen Munnig, Dietmar Wastian, Wolfgang Lorenz, Berthold Keggenhoff
  • Publication number: 20040267061
    Abstract: The invention relates to a process for the production of dinitrotoluene by the two-stage nitration of toluene.
    Type: Application
    Filed: February 17, 2004
    Publication date: December 30, 2004
    Inventors: Erwin Dieterich, Anke Hielscher, Berthold Keggenhoff, Manfred Keller-Killewald, Jurgen Munnig, Dietmar Wastian
  • Publication number: 20040267062
    Abstract: The present invention relates to a process for working up organic secondary components which are formed in the one-stage or two-stage nitration of toluene to dinitrotoluene. These organic secondary components are present in the acidic and alkaline waste water from the dinitrotoluene washing step and in the aqueous distillate from the sulfuric acid concentration step, together with small amounts of mononitrotoluene and dinitrotoluene.
    Type: Application
    Filed: June 28, 2004
    Publication date: December 30, 2004
    Inventors: Jurgen Munnig, Dietmar Wastian, Wolfgang Lorenz, Berthold Keggenhoff
  • Patent number: 6528690
    Abstract: Dinitrotoluene (DNT) is produced by the adiabatic nitration of toluene with nitric acid at a temperature of from about 60 to about 200° C. and at a molar ratio of toluene to nitric acid of from about 1:1.5 to about 1:3.0. The reaction mixture thus-obtained is concentrated to a water content of up to 30% by weight. The dinitrotoluene which is present in the reaction mixture is at least partially (if not completely) removed from the reaction mixture either before or after concentration of the reaction mixture. The DNT which is still present in the vapor generated during the concentration of the reaction mixture is kept liquid by the addition of a solvent to the vapors generated during concentration of the reaction mixture. The solvent added to vapor, together with any DNT present in the vapor is recovered. This solvent/DNT mixture may be recycled directly to the reaction vessel. The solvent/DNT mixture may also be separated. The separated solvent may be recycled to the solvent addition step.
    Type: Grant
    Filed: October 10, 1998
    Date of Patent: March 4, 2003
    Assignee: Bayer Aktiengesellschaft
    Inventors: Uwe Klingler, Hans-Georg Pirkl, Thomas Schieb, Dietmar Wastian
  • Patent number: 6506948
    Abstract: This invention relates to an improvement in a process for the production of dinitrotoluene and particularly to the recovery of dinitrotoluene and organic by-products from the wastewater and wash waters generated in the process. Wastewater and wash water streams contaminated with residual levels of mononitrotoluene, dinitrotoluene, and organic by-products, formed in the purification process, are contacted with toluene. An organic phase and an aqueous phase are generated. The phases are separated and the dinitrotoluene recovered from the organic phase.
    Type: Grant
    Filed: February 7, 2002
    Date of Patent: January 14, 2003
    Assignee: Air Products and Chemicals, Inc.
    Inventor: John Edward Sawicki
  • Patent number: 6291726
    Abstract: The nitration of aromatic compounds is achieved in high yield and selectivity by using oxygen activated by an inorganic catalyst and nitrogen dioxide. Since this process uses neither concentration nitric nor sulfuric acids, the generation of spent waste acid does not occur. Furthermore, the process does not encounter the problem of high costs associated with the generation of ozone as in an alternative nitration process. Since the solubility of oxygen in a reaction medium is increased by using pressurized oxygen, nitrogen dioxide is activated by a porous inorganic oxide and thus an aromatic compound(e.g., benzene) is nitrated into a nitro compound (e.g., PhNO2), the reaction rate is significantly increased, and the recovery of reactants is easy due to the insolubility of the catalyst.
    Type: Grant
    Filed: October 18, 2000
    Date of Patent: September 18, 2001
    Assignee: Inha University Foundation
    Inventors: Bon-Su Lee, Kyoo-Hyun Chung, Yoon-Sik Lee, Young-Gyu Kim
  • Patent number: 6288289
    Abstract: An integrated process for treating alkaline wash water effluent from nitroaromatic manufacture, principally containing nitro-hydroxy-aromatic compounds is described. The integrated process concentrates the alkaline wash water to recover chemicals and water prior to treating the concentrate through supercritical water oxidation. The supercritical water oxidation step consists of treating the concentrate in the presence of an oxygen source at conditions, which are supercritical for water to cause a substantial portion of the organic component of the concentrate to oxidize. The product effluent includes a gaseous component and a clean water component, and in the event that insoluble ash is formed, an ash component. The new integrated process results in reduced chemical and water consumption compared to existing processes. In addition, the treated wash water effluent can be recycled to process or directly discharged.
    Type: Grant
    Filed: January 27, 2000
    Date of Patent: September 11, 2001
    Assignee: Noram Engineering and Constructors Ltd.
    Inventors: David Anthony Boyd, Stuart Alan Gairns, Alfred Alexander Guenkel
  • Patent number: 6258986
    Abstract: Dinitrotoluene is produced by nitrating toluene with nitrating acid under adiabatic conditions in a manner such that some mononitrotoluene is present in reaction mixture. The nitration reaction mixture is then treated to remove at least 5% by weight of water before the reaction mixture is separated into an acid phase and an organic phase. The product dinitrotoluene is recovered from the organic phase. The acid phase may be recycled after nitric acid has been added to replace that which was used in the nitration reaction.
    Type: Grant
    Filed: August 3, 1995
    Date of Patent: July 10, 2001
    Assignee: Bayer Aktiengesellschaft
    Inventors: Uwe Klingler, Thomas Schieb, Dietmar Wastian, Gerhard Wiechers, Jürgen Zimmerman
  • Patent number: 6069277
    Abstract: The present invention relates to a process to aminate electrophilic aromatic compounds by vicarious nucleophilic substitution of hydrogen using quaternary hydrazinium salts. The use of trialkylhydrazinium halide, e.g., trimethylhydrazinium iodide, as well as hydroxylamine, alkoxylamines, and 4-amino-1,2,4-triazole to produce aminated aromatic structures, such as 1,3-diamino-2,4,6-trinitrobenzene (DATB), 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and 3,5-diamino-2,4,6-trinitrotoluene (DATNT), is described. DATB and TATB are useful insensitive high explosives. TATB is also used for the preparation of benzenehexamine, a starting material for the synthesis of novel materials (optical imaging devices, liquid crystals, ferromagnetic compounds).
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: May 30, 2000
    Assignee: The Regents of the University of California
    Inventors: Alexander R. Mitchell, Philip F. Pagoria, Robert D. Schmidt
  • Patent number: 5948944
    Abstract: A multi-step process for producing DNT employing a mononitration step in a single liquid phase at an elevated temperature using a carefully controlled amount of water, followed by a phase separation step prior to dinitration of the MNT present in the resulting organic phase. This process results in a DNT product with a desired isomer ratio of 2,4-DNT to 2,6-DNT and provide relatively fast nitration rates with less by-products.
    Type: Grant
    Filed: November 18, 1998
    Date of Patent: September 7, 1999
    Assignee: Arco Chemical Technology, L.P.
    Inventors: Chunjie Zhang, Buford T. Pennington, Jeffrey W. Baird, Allen B. Quakenbush, Stephen L. Goldstein, Donald L. Lickei, Peter J. Whitman
  • Patent number: 5902910
    Abstract: This invention relates to an improved process for the production of dinitrotoluene wherein one is able to effectively employ a feed sulfuric acid, which is referred to as "weak acid" as the feed sulfuric acid for the nitration facility. The weak acid concentration, as feed, ranges from 86-91%, preferably 87-89% sulfuric acid by weight, to meet the total sulfuric acid requirements for the facility. This is accomplished by utilizing cocurrent processing in a mononitration zone and countercurrent nitration with respect to sulfuric acid in the dinitration zone.
    Type: Grant
    Filed: September 19, 1997
    Date of Patent: May 11, 1999
    Assignee: Air Products and Chemicals, Inc.
    Inventors: William Joseph Mazzafro, Stephen Ian Clarke, Mark Shedric Simpson, Richard Van Court Carr
  • Patent number: 5874654
    Abstract: Environmentally-polluting nitrocresol values are removed from admixtures of nitroaromatic compounds comprised thereof, notably the media of nitration of aromatic compounds by reacting same with aqueous HNO.sub.3 /H.sub.2 SO.sub.4, by first intimately contacting such nitroaromatic compound admixtures with an oxidizing agent comprising hydrogen peroxide, javelle water, or mixture thereof, and thereafter with a neutralizing agent; the nitroaromatic aromatic compounds thus purified are conveniently catalytically hydrogenated into aromatic amines.
    Type: Grant
    Filed: September 19, 1997
    Date of Patent: February 23, 1999
    Assignee: Rhone Poulenc Chimie
    Inventors: Antoinette Gacon-Camoz, Pascal Metivier
  • Patent number: 5820764
    Abstract: Objectionable byproduct aqueous effluents containing contaminating amounts of hydroxynitroaromatic compounds, in particular those aqueous effluents produced during the synthesis of nitroaromatic compounds, e.g., dinitrotoluenes, via reaction of an aromatic compound with nitric acid in the presence of sulfuric acid, are efficiently, facilely and economically treated/removed by (a) intimately contacting a mixture of at least one nitroaromatic compound and at least one hydroxynitroaromatic compound with an aqueous wash medium containing a neutralizing agent, (b) separating the resulting admixture into an organic phase and an aqueous phase, (c) recycling a fraction of the separated aqueous phase to the aqueous wash medium to thus constitute a portion thereof, and (d) periodically draining a fraction of the wash medium, whether to destruction thereof or to waste.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: October 13, 1998
    Assignee: Rhone-Poulenc Chimie
    Inventors: Faouzi Joulak, Louis Le Bris, Philippe Marion
  • Patent number: 5762802
    Abstract: A process for removing nitrocresols in a crude aqueous alkaline dinitrotoluene wash stream derived by nitration of toluene using a mixed acid technique followed by treatment with aqueous alkaline material in which the crude aqueous alkaline dinitrotoluene wash stream is mixed with a dilute oxidizing acid such as nitric acid, heated to 130.degree. to 180.degree. C. for a period of time required to reduce the nitrocresols to a level at which it does not precipitate from the mixed acidic wash stream at temperatures above about 60.degree. C., and removing the remaining nitrocresols by conventional methods such as adsorption or activated sludge biotreatment.
    Type: Grant
    Filed: May 1, 1997
    Date of Patent: June 9, 1998
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Richard Van Court Carr, Mark Shedrick Simpson
  • Patent number: 5763696
    Abstract: Reduction of dinitrotoluene impurity in water is achieved by distillation in the presence of nitric acid. A suitable process for such reduction comprises (a) contacting said composition with nitric acid to provide a nitric acid-containing composition, (b) distilling at least a portion of said water in said nitric acid-containing composition to provide vaporized water containing a reduced concentration of said dinitrotoluene, and (c) separating said vaporized water from said nitric acid-containing composition.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: June 9, 1998
    Assignee: Arco Chemical Technology, L.P.
    Inventors: Allen B. Quakenbush, Majid N. Keyvani, Michael C. Fullington, James L. Meyer
  • Patent number: 5756867
    Abstract: A process for the removal and recovery of nitric acid, sulphuric acid and nitrous oxide (NO.sub.x) from crude dinitrotoluene (DNT) obtained by nitrating with a nitrating acid, a benzene derivative selected from the group consisting of tolulene or mononitrotoluene (after separation from the dinitrotoluene from the nitrating acid, wherein the crude dinitrotoluene is extracted in a plurality of steps whereby a dilute aqueous solution of nitric, sulfuric and nitrous acids countercurrently contacts the crude dinitrotoluene, the volume ratio of the dinitrotoluene to the aqueous solution being between 1:3 and 10:1, the extraction steps resulting in the formation of an aqueous extract which is blended directly into the nitrating acid for re-use in the acid nitration of the benzene derivative.
    Type: Grant
    Filed: September 15, 1995
    Date of Patent: May 26, 1998
    Assignee: Josef Meissner GmbH & Co.
    Inventors: Heinrich Hermann, Jurgen Gebauer
  • Patent number: 5728901
    Abstract: A process for preparing a nitrated arene which comprises reacting an arene and nitric acid in the presence of a water tolerant Lewis acid catalyst under process conditions sufficient to form the nitrated arene and recovering the nitrated arene. Suitable Lewis acid catalysts are represented by the formula M.sup.n (A.sub.1).sub.x (A.sub.2).sub.n-x whereinM is selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Sc, Hf, Lu and Li;A.sub.1 and A.sub.2 are independently selected from a perfluoroalkylsulfonate, a fluorosulfonate, a hexafluorophosphate or a nitrate;n is the common oxidation state of M andx is 1, 2, 3 or 4 with the proviso that x is never greater than n.The catalysts of the process are isolatable from water and can be recycled for subsequent process cycles.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: March 17, 1998
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Dorai Ramprasad, Francis Joseph Waller, Anthony Gerard Barrett, David Christopher Braddock
  • Patent number: 5696305
    Abstract: Nitroaromatic compounds are produced by continuously reacting an aromatic compound with nitrating acid. The reaction mixture is separated into an organic phase from which the desired nitroaromatic compound is recovered and an acid phase. The acid phase is subjected to flash evaporation to remove at least 5% by weight of the water present therein. The vapors generated during the flash evaporation are introduced into a jet spray of coolant to produce a condensate made up coolant, condensed vapors and suspended organic compounds. A portion of the condensate is subjected to phase separation to remove water and organic compounds present therein. The water and organic compounds may be reused. The process of the present invention is particularly advantageous in that deposits which block pipelines and interfere with heat transfer are not generated.
    Type: Grant
    Filed: August 3, 1995
    Date of Patent: December 9, 1997
    Assignee: Bayer Aktiengesellschaft
    Inventors: Uwe Klingler, Thomas Schieb, Gerhard Wiechers, Jurgen Zimmermann
  • Patent number: 5689018
    Abstract: Dinitrotoluene is produced from toluene and nitric acid in the presence of sulfuric acid in a two stage process in the first stage, toluene and nitric acid are reacted under isothermal conditions in amounts such that mononitrotoluene is produced. The reaction mixture is then separated into an organic phase and an acid phase. The organic phase is then further reacted with nitric acid under adiabatic conditions to produce dinitrotoluene. The reaction mixture is then separated into an organic phase and an acid phase. Dinitrotoluene is recovered from the organic phase. After at least 5% by weight water is removed from the acid phase and sufficient nitric acid to replace that consumed during the nitration reaction has been added, the acid phase may be recycled.
    Type: Grant
    Filed: August 3, 1995
    Date of Patent: November 18, 1997
    Assignee: Bayer Aktiengesellschaft
    Inventors: Uwe Klingler, Thomas Schieb, Gerhard Wiechers, Jurgen Zimmermann
  • Patent number: 5679873
    Abstract: Dinitrotoluene is produced in a two-stage process from toluene and nitric acid in the presence of sulfuric acid under adiabatic conditions in the presence of nitrating acids made up of specified components. The reaction product of the first phase is separated into an acid phase and an organic phase containing the mononitrotoluene. Some water is removed from the acid phase, nitric acid is added and the resultant mixture is recycled. The organic phase containing mononitrotoluene is further nitrated to produce the dinitrotoluene. This nitration mixture is also separated into an acid phase and an organic phase. The acid phase is treated to remove some water, nitric acid is added and the resultant acid mixture is recycled. Dinitrotoluene is recovered from the organic phase. This process is advantageous in that dilute nitric acid may be used and the heat of the nitration reaction is utilized.
    Type: Grant
    Filed: August 3, 1995
    Date of Patent: October 21, 1997
    Assignee: Bayer Aktiengesellschaft
    Inventors: Uwe Klingler, Thomas Schieb, Gerhard Wiechers, Jurgen Zimmermann
  • Patent number: 5663462
    Abstract: Dinitrotoluene and isomer mixtures of dinitrotoluene are produced in a single stage, continuous process by nitrating mononitrotoluene or an isomer mixture of mononitrotoluene in which the ortho-mononitrotoluene content is low with a nitrating acid made up of (1) from about 80 to about 100 wt. % inorganic constituents and (2) up to 20 wt. % organic constituents. The inorganic constituents of the nitrating acid include: (a) from about 60 to about 90 wt. % sulfuric acid, (b) from about 1 to about 20 wt. % nitric acid, and (c) at least 5 wt. % water. The organic constituents of the nitrating acid include: from about 70 to about 100% by weight nitrotoluene isomers and up to about 30% by weight nitration by-products. The nitration reaction is carrier out under adiabatic conditions. The molar ratio of nitric acid to mononitrotoluene during the nitration reaction is generally from about 0.7:1 to about 1.4:1.
    Type: Grant
    Filed: June 4, 1996
    Date of Patent: September 2, 1997
    Assignee: Bayer Aktiengesellschaft
    Inventors: Uwe Klingler, Thomas Schieb, Gerhard Wiechers
  • Patent number: 5633406
    Abstract: The present invention relates to a process to produce 1,3-diamino-2,4,6-trinitrobenzene (DATB) or 1,3,5-triamino-2,4,6,-trinitrobenzene (TATB) by:(a) reacting at ambient pressure and a temperature of between about 0.degree. and 50.degree. C. for between about 0.1 and 24 hr, a trinitroaromatic compound of structure V: ##STR1## wherein X, Y, and Z are each independently selected from the group consisting of --H and --NH.sub.
    Type: Grant
    Filed: May 12, 1995
    Date of Patent: May 27, 1997
    Assignee: The Regents of the University of California
    Inventors: Alexander R. Mitchell, Philip F. Pagoria, Robert D. Schmidt
  • Patent number: 5616818
    Abstract: An aromatic compound is polynitrated in a continuous process in a single apparatus under adiabatic conditions in an emulsion as the reaction medium. From 1.3 to 3.5 mol of HNO.sub.3 per mol of aromatic compound are introduced in the form of a nitronium ion solution into the reactor with the aromatic compound under conditions such that an emulsion forms. The emulsion, which has a tendency to coalesce, is maintained by repeated dispersion. The first dispersion of the liquid streams to produce the emulsion takes place in less than one second. At least 20% of the total amount of HNO.sub.3 to be used should generally be present during this first dispersion. It is preferred, however, that the total amount of nitronium ion solution to be used be present at the time the aromatic compound and nitronium ion solution are first dispersed.
    Type: Grant
    Filed: October 13, 1995
    Date of Patent: April 1, 1997
    Assignee: Bayer Aktiengesellschaft
    Inventors: Hans-Georg Pirkl, Reinhard Schom acker, Uwe Klingler, Thomas Schieb, Gerhard Wiechers, J urgen Zimmermann
  • Patent number: 5554299
    Abstract: Objectionable byproduct aqueous effluents containing contaminating amounts of hydroxynitroaromatic compounds, in particular those aqueous effluents produced during the synthesis of nitroaromatic compounds, e.g., dinitrotoluenes, via reaction of an aromatic compound with nitric acid in the presence of sulfuric acid, are efficiently, facilely and economically treated/removed by (a) intimately contacting a mixture of at least one nitroaromatic compound and at least one hydroxynitroaromatic compound with an aqueous wash medium containing a neutralizing agent, (b) separating the resulting admixture into an organic phase and an aqueous phase, (c) recycling a fraction of the separated aqueous phase to the aqueous wash medium to thus constitute a portion thereof, and (d) periodically draining a fraction of the wash medium, whether to destruction thereof or to waste.
    Type: Grant
    Filed: January 3, 1995
    Date of Patent: September 10, 1996
    Assignee: Rhone-Poulenc Chimie
    Inventors: Faouzi Joulak, Louis Le Bris, Philippe Marion