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CN-122029145-A - Method and device for drying and/or purifying nitrate esters

CN122029145ACN 122029145 ACN122029145 ACN 122029145ACN-122029145-A

Abstract

The present invention relates to a process for drying and/or purifying, preferably for drying and purifying, aliphatic or cycloaliphatic nitrates (nitrates), in particular for removing water and volatile and/or volatizable impurities produced in particular during the production and/or washing of the nitrates, and to the corresponding use and to corresponding devices and systems for carrying out the process.

Inventors

  • POLMANN JURGEN
  • HANDEL MIRKO
  • Tim bergmann
  • Dieter Ober
  • Daniel. Wen Shi

Assignees

  • 约瑟夫·迈斯纳两合公司

Dates

Publication Date
20260512
Application Date
20240710
Priority Date
20230928

Claims (20)

  1. 1. A process for drying and/or purifying, preferably for drying and purifying, aliphatic or cycloaliphatic nitrates (nitrates), in particular for removing water and volatile impurities which are produced in particular during the production and/or washing of the nitrates, The method comprises the following method steps: (a) First, the crude nitrate obtained from the production process is washed with a washing medium, then the washing medium is separated, (B) Subsequently, the washed crude nitrate obtained in process step (a) is dried and/or purified, preferably dried and purified, by contact with an inert gas, in particular by flow through (permeation), in particular in such a way that the water present in the washed crude nitrate is removed, and at the same time and/or in the same way volatile impurities, in particular generated during the production of the nitrate and/or washing, are removed.
  2. 2. The method according to claim 1, Wherein the nitrate is liquid under standard conditions, in particular at a pressure of 1.013 bar and a relative atmospheric humidity of 0% (standard conditions according to DIN 1343, STPD), and/or is present in liquid form, and/or Wherein the nitrate is a nitrate of a mono-or poly-aliphatic or cycloaliphatic alcohol, and/or Wherein the nitrate is selected from (i) nitrate esters of aliphatic or cycloaliphatic alkanols, in particular nitrate esters of linear or branched aliphatic or cycloaliphatic alkanols, preferably nitrate esters of hexanol, heptanol, octanol, ethylhexyl alcohol and cyclohexanol, (ii) nitrate esters of aliphatic alkanediols, in particular nitrate esters of ethylene glycol and propylene glycol and oligomers and polymers thereof, such as nitrate esters of ethylene glycol or propylene glycol, ethylene or propylene triethylene glycol and polyethylene glycol or polypropylene glycol, (iii) nitrate esters of aliphatic alkanetriols, in particular nitrate esters of trimethylolethane, trimethylolpropane, butanetriol and glycerol, (iv) nitrate esters of quaternary or poly-aliphatic alkanols.
  3. 3. The method according to claim 1 or 2, Wherein the volatile impurities are selected from (i) unreacted and/or partially reacted starting materials and/or starting reagents, (ii) nitrated and non-nitrated reaction by-products, (iii) degradation and oxidation products of nitrated and by-products, (iv) inorganic acids, in particular sulfuric acid, nitric acid and nitrous acid, preferably nitric acid, (v) organic acids, in particular formic acid, acetic acid, oxalic acid, carbonic acid and hydrocyanic acid, (vi) nitrogenous bases, in particular ammonia (NH 3 ), (vii) nitrogen oxides, in particular nitrogen monoxide (NO), nitrogen dioxide (NO 2 ) and nitrous oxide (N 2 O), and nitrous and other nitrogen oxides (NO x ), (viii) carbon oxides, in particular carbon monoxide (CO) and carbon dioxide (CO 2 ), (ix) solvent and/or scrubbing medium residues, and/or Wherein the volatile impurities to be removed have a higher volatility, in particular a higher vapor pressure and/or a lower boiling point than the nitrate to be purified, in particular based on the vapor pressure of the nitrate under standard conditions (pressure 1.013bar; atmospheric humidity 0% [ standard conditions according to DIN 1343, STPD ]) and/or in particular based on the boiling point of the nitrate under standard conditions (pressure 1.013bar; atmospheric humidity 0% [ standard conditions according to DIN 1343, STPD ]), in particular wherein the vapor pressure of the volatile impurities to be removed is at least 5 mbar, preferably at least 7.5 mbar, more preferably at least 10 mbar, higher than the nitrate to be purified, and/or in particular wherein the boiling point of the volatile impurities to be removed is at least 1 ℃, preferably at least 2.5 ℃ and more preferably at least 5 ℃ lower than the nitrate to be purified.
  4. 4. The method according to any of the preceding claims, Wherein the process step (a) and/or the washing is carried out as liquid-liquid extraction, and/or Wherein process step (a) comprises an acidic, basic (alkaline) and/or neutral wash, in particular at least one basic (alkaline) and/or neutral wash, preferably an acidic, basic (alkaline) and neutral wash, and/or Wherein the process step (a) and/or washing is carried out in one or more washing stages, preferably in one, two or three washing stages, more preferably in two or three washing stages, in particular wherein each washing stage comprises one or more washing and/or extraction cycles (steps), and/or Wherein the process step (a) and/or the washing is carried out with an aqueous-based washing medium, in particular wherein the aqueous-based washing medium is set neutral, acidic or basic (alkaline-containing).
  5. 5. The method according to any of the preceding claims, Wherein the process step (a) and/or the washing is carried out in at least two, in particular three washing stages, in particular wherein the washing stages comprise at least one alkaline (alkaline) washing stage and one final neutral washing stage, preferably wherein the washing stages comprise a first acidic washing stage followed by a second alkaline (alkaline) washing stage and a final third neutral washing stage.
  6. 6. The method according to any of the preceding claims, Wherein process step (a) and/or washing, in particular in each washing stage, is carried out in cross-flow or counter-flow or a combination of cross-flow and counter-flow, preferably the washing medium is recovered.
  7. 7. The method according to any of the preceding claims, Wherein in process step (a) the separation of the washing medium is carried out by a separation device (separator), in particular by a static separation device or a centrifugal separator.
  8. 8. The method according to any of the preceding claims, Wherein method step (b) is carried out in a drying and/or purifying apparatus, preferably a drying and purifying apparatus; In particular, wherein the washed crude nitrate obtained in process step (a) is transferred in process step (b) to a drying and/or cleaning plant, preferably a drying and cleaning plant, and/or In particular wherein the drying and/or purifying means, preferably the drying and purifying means, comprises a column and/or a gas/liquid reactor or stripping means, and preferably a column, in particular a single-stage or multistage column, preferably a packed bed column, a sieve plate column, a bubble tray column or a falling film column or a combination thereof.
  9. 9. The method according to any of the preceding claims, Wherein in process step (b) the drying and/or the cleaning, preferably the drying and cleaning, is carried out as a continuous or discontinuous, in particular continuous, process.
  10. 10. The method according to any of the preceding claims, Wherein in process step (b) the drying and/or purification, preferably drying and purification, is carried out as gas-liquid extraction and/or by desorption, in particular as gas-liquid extraction.
  11. 11. Method for drying and/or purifying, preferably for drying and purifying, aliphatic or cycloaliphatic nitrates (nitrates), in particular for removing water and volatile and/or volatile impurities generated during the production and/or washing of the nitrates, in particular according to one of the preceding claims, The method comprises the following method steps: (a) First, the crude nitrate obtained from the production process is washed with a washing medium, then the washing medium is separated, Wherein the process step (a) and/or the washing is carried out as liquid-liquid extraction; (b) Subsequently, the washed crude nitrate obtained in process step (a) is dried and/or purified, preferably dried and purified, in particular in such a way that the water present in the washed crude nitrate is removed, and at the same time and/or in the same way volatile and/or volatile impurities, in particular generated during the production of the nitrate and/or washing, are removed by contact with an inert gas, in particular by means of through-flow (osmosis), Wherein the drying and/or purification, preferably the drying and purification, is carried out as a gas-liquid extraction and/or by desorption, in particular as a gas-liquid extraction; In particular wherein the volatile and/or volatizable impurities are selected from the group consisting of (i) unreacted and/or partially reacted starting materials and/or starting reagents, (ii) nitrated and non-nitrated reaction by-products, (iii) degradation and oxidation products of nitrated and by-products, (iv) mineral acids, in particular sulfuric acid, nitric acid and nitrous acid, preferably nitric acid, (v) organic acids, in particular formic acid, acetic acid, oxalic acid, carbonic acid and hydrocyanic acid, (vi) nitrogenous bases, in particular ammonia (NH 3 ), (vii) nitrogen oxides, in particular Nitric Oxide (NO), nitrogen dioxide (NO 2 ) and nitrous oxide (N 2 O), and nitrous and other nitrogen oxides (NO x ), (viii) carbon oxides, in particular carbon monoxide (CO) and carbon dioxide (CO 2 ), (ix) solvent and/or washing medium residues, and/or In particular wherein the volatile and/or volatizable impurities to be removed have a higher volatility, in particular a higher vapor pressure and/or a lower boiling point than the nitrate to be purified, in particular based on the vapor pressure of the nitrate under standard conditions (pressure 1.013bar; atmospheric humidity 0% [ standard conditions according to DIN 1343, STPD ]) and/or based on the boiling point of the nitrate under standard conditions (pressure 1.013bar; atmospheric humidity 0% [ standard conditions according to DIN 1343, STPD ]).
  12. 12. The method according to any of the preceding claims, Wherein in process step (b) the washed crude nitrate obtained in process step (a) is used directly, and/or in process step (b) the washed crude nitrate obtained in step (a) is used in concentrated or undiluted form, and/or Wherein in process step (b) no (additional) solvent and/or dispersant for drying and/or cleaning, preferably drying and cleaning, is added to the washed crude nitrate obtained in process step (a).
  13. 13. The method according to any of the preceding claims, Wherein in process step (b) the inert gas is selected and/or formed in such a way that it does not react with respect to the nitrate under the conditions of process step (b), and/or Wherein in process step (b) the inert gas is selected from the group consisting of nitrogen, oxygen, a noble gas, in particular argon, hydrogen, carbon oxides and in particular air, and mixtures thereof, preferably from the group consisting of nitrogen, oxygen, a noble gas, in particular argon, and in particular air, and particularly preferably from the group consisting of nitrogen, oxygen and in particular air.
  14. 14. The method according to any of the preceding claims, Wherein in process step (b) the contacting, in particular the passing, of the washed crude nitrate obtained in process step (a) with an inert gas is carried out in a cross-flow and/or counter-flow, preferably counter-flow, manner; In particular in which the inert gas is directed to flow upwards and the nitrate is directed to flow downwards, in particular in a drying and/or purification apparatus, preferably a drying and purification apparatus, more preferably a column, in particular a single-stage or multistage column, preferably a packed bed column, a sieve plate column, a bubble tray column or a falling film column or a combination thereof, and/or in a gas/liquid reactor or stripping apparatus.
  15. 15. The method according to any of the preceding claims, Wherein in process step (b) the contacting, in particular the passing, of the nitrate with the inert gas takes place and/or is carried out in such a way that the inert gas is distributed in the nitrate, in particular finely distributed, and/or Wherein in process step (b) the inert gas is introduced into the nitrate esters, preferably by means of nozzles, jet mixers, jet pumps, injectors, spray guns, screen plates and/or microporous membranes, more preferably by means of nozzles, jet mixers and/or microporous membranes, with and/or with a dispersion distribution, in particular a finely dispersed distribution.
  16. 16. The method according to any of the preceding claims, Wherein in process step (b) the inert gas is used in dry form; In particular wherein the dew point of the inert gas in dry form is lower than the temperature at which step (b) of the process of the invention is carried out, in particular wherein the dew point is preferably at least 5 ℃, more preferably at least 10 ℃, most preferably at least 15 ℃ lower than the temperature at which step (b) of the process of the invention is carried out, and/or In particular wherein the inert gas supplied, in particular at the beginning of process step (b) and/or initially supplied, has a dew point of-20 ℃ or less, in particular-30 ℃ or less, preferably-35 ℃ or less, more preferably-40 ℃ or less, and/or a dew point of-80 ℃ or more, in particular-65 ℃ or more, preferably-55 ℃ or more, more preferably-50 ℃ or more, and/or In particular wherein the dew point of the inert gas supplied, in particular at the beginning of process step (b) and/or initially supplied, is in the range from-20 ℃ to-80 ℃, in particular from-30 ℃ to-65 ℃, preferably from-35 ℃ to-55 ℃, more preferably from-40 ℃ to-50 ℃, and/or In particular wherein the relative humidity of the inert gas, in particular supplied at the beginning of process step (b) and/or initially supplied, is in the range of 0 to 95%, in particular 0 to 90%, preferably 0 to 85%, more preferably 0 to 80%.
  17. 17. The method according to any of the preceding claims, Wherein in process step (b) drying and/or cleaning, preferably drying and cleaning and/or contacting, in particular through-flow, with an inert gas is carried out at a volumetric flow rate of 100L/h/kg nitrate (L/h/kg nitrate to be dried and/or free of volatile impurities) or more, in particular 200L/h/kg nitrate or more, preferably 300L/h/kg nitrate or more, more preferably 350L/h/kg nitrate or more, and/or at a volumetric flow rate of 600L/h/kg nitrate or less, in particular 500L/h/kg nitrate or less, preferably 450L/h/kg nitrate or less, more preferably 425L/h/kg nitrate or less, and/or Wherein in process step (b) drying and/or purging, preferably drying and purging and/or contacting, in particular through-flow, with an inert gas is performed at a volumetric flow rate in the range of 100L/h/kg nitrate to 600L/h/kg nitrate, in particular 200L/h/kg nitrate to 500L/h/kg nitrate, preferably 300L/h/kg nitrate to 450L/h/kg nitrate, more preferably 350L/h/kg nitrate to 425L/h/kg nitrate.
  18. 18. The method according to any of the preceding claims, Wherein in process step (b) drying and/or purging, preferably drying and purging and/or contacting with an inert gas, in particular through-flow, is performed with a residence time of the nitrate in the presence of inert gas of 30 seconds or more, in particular 1 minute or more, preferably 3 minutes or more, more preferably 7 minutes or more, and/or with a residence time of the nitrate in the presence of inert gas of 20 minutes or less, in particular 17 minutes or less, preferably 14 minutes or less, more preferably 12 minutes or less, and/or Wherein in process step (b) drying and/or purging, preferably drying and purging and/or contacting with an inert gas, in particular through-flow, is performed, the residence time of the nitrate esters in the presence of inert gas is from 30 seconds to 20 minutes, in particular from 1 minute to 17 minutes, preferably from 3 minutes to 14 minutes, more preferably from 7 minutes to 12 minutes.
  19. 19. The method according to any of the preceding claims, Wherein in process step (b) the vapor pressure of the nitrate is less than 100 mbar, in particular less than 80 mbar, preferably less than 60 mbar, more preferably less than 50 mbar, and/or at a temperature at which drying and/or purification, preferably drying and purification and/or contact with an inert gas, in particular throughflow, is performed Wherein in process step (b) drying and/or purification, preferably drying and purification and/or contact with an inert gas, in particular through-flow, is carried out at a temperature of more than 0 ℃, in particular more than 5 ℃, preferably more than 7.5 ℃, more preferably more than 10 ℃, and/or less than 60 ℃, in particular less than 50 ℃, preferably less than 40 ℃, more preferably less than 35 ℃, and/or Wherein in process step (b) drying and/or purging, preferably drying and purging and/or contacting with an inert gas, in particular through-flow, is carried out at a temperature in the range of 0 ℃ to 60 ℃, in particular 5 ℃ to 50 ℃, preferably 7.5 ℃ to 35 ℃, more preferably 10 ℃ to 30 ℃.
  20. 20. The method according to any of the preceding claims, Wherein in process step (b) drying and/or purification, preferably drying and purification and/or contact with inert gas, in particular throughflow, is carried out at atmospheric pressure (normal pressure; 1.01325 bar) or vacuum (reduced pressure) or superatmospheric pressure, preferably at atmospheric pressure, and/or Wherein in process step (b) the drying and/or purging, preferably the drying and purging and/or the contacting with inert gas, in particular the through-flow, is carried out at an absolute pressure of from 0.1 bar to 3 bar, in particular from 0.3 bar to 1.2 bar, preferably from 0.5 bar to 1.1 bar, more preferably about 1 bar.

Description

Method and device for drying and/or purifying nitrate esters Technical Field The present invention relates to the technical field of production and in particular drying and/or purification of aliphatic and cycloaliphatic nitrates (nitrates) and aims at providing dry and/or anhydrous and pure nitrates. In particular, the present invention relates to a process for drying and/or purifying aliphatic or cycloaliphatic nitrates (nitrates), in particular for removing water and volatile impurities which are particularly generated during the production and/or washing of the nitrates. The invention further relates to a device for drying and/or purifying aliphatic or cycloaliphatic nitrates and to a production plant for producing aliphatic or cycloaliphatic nitrates. Finally, the invention relates to the use of inert gases for drying and/or purifying, preferably for drying and purifying, crude aliphatic or cycloaliphatic nitrates (nitrates) obtained from a production process. Background Aliphatic and/or cycloaliphatic organic nitrates (nitrates) are the reaction products of the corresponding aliphatic and/or cycloaliphatic alcohols with nitric acid. Nitrate is generally produced in a continuously operated apparatus by reacting the alcohol directly with nitric acid, or in the presence of sulfuric acid as catalyst and water binder (for example by the method according to Schmid-Meissner or Biazzi, by the syringe method or by the n.a.b. process of Nielsen and Brunnberg, or by the modified method according to EP1792891 A1). The nitration of alcohols (i.e. their conversion to nitrates) usually takes place in the liquid phase, either as pure substances or as mixtures, or else in solution in inert, water-immiscible solvents. Organic nitrates are particularly common in the field of explosive chemistry (e.g., nitroglycerine, ethylene glycol dinitrate, etc.), as well as in the pharmaceutical industry (e.g., sterol nitrates, etc.) or in the fuel industry, particularly as additives therein. For example, one known and widely used additive in the fuel industry is ethylhexyl nitrate (EHN), which is used as an additive to diesel fuel to increase cetane number. Other widely used nitrates are in particular pentaerythritol tetranitrate (PETN), glycerol trinitrate (NGL), ethylene Glycol Dinitrate (EGDN) and the like. Cetane number is a number describing the flammability of diesel fuel, the higher the cetane number, the more flammable the fuel. In this case, it was first determined that the higher the proportion of linear hydrocarbon molecules contained in the fuel oil, the better the pyrophoricity thereof, which is an ideal characteristic especially in diesel engines. Compression ignition engines (diesel engines) therefore tend to be more difficult to start with lower cetane number fuels and are more noisy when operated in the cold state. Conversely, higher cetane fuels tend to make cold starts easier, engine noise lower, and reduce white smoke ("cold smoke") generated by incomplete combustion. Accordingly, there is a general preference for diesel fuels having a high cetane number, which is becoming more apparent due to increasingly stringent emission regulations, since the minimum cetane number is typically specified in the specifications of automotive diesel. Accordingly, many diesel fuel compositions contain additives in the form of ignition improvers, also known as cetane boost additives or cetane improvers, to ensure compliance with these specifications and to generally improve the combustion performance of the fuel. The ignition improving additive most commonly used in diesel fuel may be 2-ethylhexyl nitrate (EHN). It is especially capable of shortening the ignition delay of the fuel to which the additive is added. The crude nitrates obtained from the production process mentioned at the beginning have to undergo washing (in particular multistage washing) and additional purification steps before being used, for example, as ignition improving additives and/or their further processing in this respect. This is necessary to remove dissolved or suspended impurities (e.g., sulfuric acid, nitric acid, nitrous gases, etc.) from the crude nitrate as well as by-products of the oxidative degradation of the starting alcohol. In this way, the stability of the nitrate esters, which mainly constitute the high sensitivity explosive, can be improved. Generally, the process of washing the crude nitrate to remove acids dissolved and suspended therein from the nitration mixture and to remove other impurities that are acidic or extractable with detergents includes three steps, acidic washing, basic washing and neutral washing (see, e.g., t. Urbanski, volume 2, page 97 and later, particularly fig. 43, 44, 59 and 60,Pergamon Press,1985 reprinting). However, washing the crude nitrate directly with, for example, a sodium carbonate solution, i.e. omitting the "acid wash" washing stage, is also practiced to some extent and belongs to the prior art. Water is ge