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EP-4276088-B1 - USE OF A CONTAINER FOR THE STORAGE OF A SATURATED ALIPHATIC C6-C12 CARBOXYLIC ACID

EP4276088B1EP 4276088 B1EP4276088 B1EP 4276088B1EP-4276088-B1

Inventors

  • TELES, JOAQUIM HENRIQUE
  • HAMANN, Jessica Nadine
  • LIANG, SHELUE
  • RITTINGER, STEFAN

Dates

Publication Date
20260513
Application Date
20211012

Claims (9)

  1. Use of a container with an inner volume of 0.05 to 10000 m 3 for the transport and storage of a liquid comprising a non-substituted saturated aliphatic C 6-12 carboxylic acid or a mixture thereof, whereas the liquid has a saturated aliphatic C 6-12 carboxylic acid content of 99 to 100 wt.-% and occupies 1 to 99% of the inner volume of the container with a gas phase above the liquid, wherein a) the container is a metallic container, in which the walls are solely made of a metal or at least contain a metallic mantle, and b) the gas phase above the liquid is an inert gas phase containing nitrogen, helium, neon, argon, krypton, xenon, hydrogen, carbon dioxide, carbon monoxide or a mixture thereof, having a molecular oxygen content of 0 to 100 vol.-ppm.
  2. The use of the container of claim 1, wherein the container is a stainless steel container.
  3. The use of the container of claims 1 to 2, wherein the container is a mobile container with an inner volume of 0.05 to 120 m 3 .
  4. The use of the container of claims 1 to 3, wherein the non-substituted saturated aliphatic C 6-12 carboxylic acid is octanoic acid, 2-ethylhexanoic acid, nonanoic acid, 3,5,5-trimethylhexanoic acid, decanoic acid, 2-propylheptanoic acid or dodecanoic acid, or a mixture thereof.
  5. The use of the container of claim 4, wherein the non-substituted saturated aliphatic C 6-12 carboxylic acid is 2-ethylhexanoic acid.
  6. The use of the container of claims 1 to 5, wherein the liquid has an active oxygen content of 0 to 100 wt.-ppm.
  7. The use of the container of claims 1 to 6, wherein the liquid occupies 90 to 99% of the inner volume of the container.
  8. The use of the container of claims 1 to 7, wherein the inert gas phase has a molecular oxygen content of ≤ 10 vol.-ppm.
  9. The use of the container of claims 1 to 8, wherein the inert gas phase contains ≥ 99.9 vol.-% nitrogen, calculated on a basis, in which the vapor of the saturated aliphatic C 6-12 carboxylic acids vaporized from the liquid was deducted and the remaining gas phase set to 100 vol.-%.

Description

The present invention relates to the use of a container with an inner volume of 0.05 to 10000 m3 for the storage and transport of a liquid comprising a non-substituted saturated aliphatic C6-12 carboxylic acid or a mixture thereof, whereas the liquid has a non-substituted saturated aliphatic C6-12 carboxylic acid content of 99 to 100 wt.-%, in which the liquid occupies 1 to 99% of the inner volume of the container and a gas phase is present above the liquid. Saturated aliphatic carboxylic acids are important intermediates globally with a wide range of applications. They can be used as such, but are typically further processed to metal salts, esters, amides, anhydrides, acid chlorides, and other derivatives. Overall, they are important intermediates for the production of a wide variety of compounds such as metal salts and metal soaps, flavors, fragrances, pharmaceutical and agrochemical ingredients, cosmetic ingredients, plasticizers, paints, coating additives, coolants, lubricants or catalysts for polymer processing. A very important representative of a C6-12 saturated aliphatic carboxylic acid is 2-ethylhexanoic acid. It is mainly used in the form of its derivatives as for example its metal salts or esters for their use as drying agents and thickeners for alkyd resins and paints, as catalysts in polyurethane foam manufacturing, as PVC stabilizers and/or plasticizers, or as anti-wear agents and corrosion inhibitors for lubricants. Esters of C6-12 saturated aliphatic carboxylic acids such as of n-heptanoic acid, n-octanoic acid, 2-ethylhexanoic acid, n-nonanoic acid or 3,5,5-trimethylhexanoic acid are also often used as lubricants. A widely used and important method for the production of saturated aliphatic C6-12 carboxylic acids is the oxidation of the corresponding aldehydes with molecular oxygen in the liquid phase in the presence or absence of a catalyst or any additives. This general synthesis route is, for example, described in J. Kubitschke et al., "Carboxylic acids, aliphatic" in Ullmann's Encyclopedia of Industrial Chemistry, 2014, Wiley-VCH Verlag GmbH & Co. KGaA, DOI: 10.1002/14356007.a05_235.pub2, chapter 4.2.1 "Aldehyde oxidation" and chapter 7 "Commercially important aliphatic carboxylic acids". The obtained C6-12 carboxylic acids are then usually purified by distillation to obtain them in a preferably pure form. However, before they are further processed to their derivatives or used otherwise, they are usually stored in immobile or mobile containers of different size and, if required, transported therein to other locations for their further use. Since most aliphatic carboxylic acids are flammable and corrosive, J. Kubitschke et al. teach in chapter 6 "Storage and transportation" of the above-mentioned article to store and transport them in corrosion-resistant containers. This implies an easy handling in stainless steel or acid-resistant plastic containers without any further specific measures and without taking specific care on the mentioned flammability. Although J. Kubitschke et al. mentioned the flammability of aliphatic carboxylic acids, an overview on various saturated aliphatic C6-12 carboxylic acids based on the data available on the European Chemicals Agency (ECHA) database, which is a publicly available electronic database of chemicals provided by the European Union, revealed typical flash points of ≥ 100°C at ambient pressure such as for example for C6:104°C for hexanoic acid;for C7:117°C for heptanoic acid;for C8:132°C for octanoic acid;118°C for 2-ethylhexanoic acid;for C9:137°C for nonanoic acid;117°C for 3,5,5-trimethylhexanoic acid;for C10:147°C for decanoic acid; andfor C12:154°C for 2-butyloctanoic acid. Flash points of ≥ 100°C are relatively high, but do not per se release from explosion preventing measures such as keeping the aliphatic carboxylic acids under an inert gas atmosphere. N. Allen depicts in his article "Hazards of high flash point liquids in relation to the ATEX 137 directive" in Hazards XXI, Symposium Series No. 155, IChemE 2009, pages 271-276 that liquids with a flash point < 40°C generally require explosion preventing measures, but also liquids with a flash point ≥ 40°C may also require such measures if the liquid is intentionally or unintentionally heated above their flash point, mists and aerosols may be formed, chemical reactions or decompositions may occur, or the liquid may be contaminated or mixed with a low flash point component. Since the flash points of saturated aliphatic C6-12 carboxylic acids are well above any temperatures that can reasonably be assumed during storage or transport, and also none of the other exceptions mentioned above apply, N. Allen confirms that the storage and transport of saturated aliphatic C6-12 carboxylic acids does not require explosion preventing measures such as the provision of an inert gas atmosphere. Summing up, the articles of J. Kubitschke et al. and N. Allen,the absence of oxygen sensitive C=C double bonds in satur