Process for packaging a dianhydrohexitol, aqueous solution of dianhydrohexitol packaged and uses thereof

Abstract

The present invention relates to a process for packaging a dianhydrohexitol, in the form of an aqueous solution in a container comprising a metal-based layer. It also relates to the container containing the aqueous solution of dianhydrohexitol.

Claims

1. A method for conditioning a dianhydrohexitol, comprising: providing an aqueous solution of dianhydrohexitol, introducing said aqueous solution of dianhydrohexitol into a container having an interior surface, and then closing said container with the aqueous solution of dianhydrohexitol in direct contact with the interior surface, said interior surface consisting of a layer based on metal, optionally covered by one of a polyester resin and epoxy resin based varnish, wherein an oxygen pressure inside the closed container is not a reduced oxygen pressure.

2. The method as claimed in claim 1, wherein the dianhydrohexitol is selected from the group consisting of isosorbide, isomannide, isoidide, and mixtures of at least two of these products.

3. The method as claimed in claim 1, wherein the aqueous solution of dianhydrohexitol has a content of dry matter of between 40% and 95%, relative to a total weight thereof.

4. The method according to claim 3, wherein the aqueous solution of dianhydrohexitol has a content of dry matter of between 50% and 90% relative to the total weight thereof.

5. The method as claimed in claim 1, wherein the layer based on metal is covered by one of a polyester resin and epoxy resin based varnish.

6. The method according to claim 1, wherein said metal comprises one of aluminum and steel.

7. A closed container containing an aqueous solution of dianhydrohexitol, said container having an interior surface in direct contact with the aqueous solution of dianhydrohexitol, said interior surface consisting of a layer based on metal, optionally coated with a varnish based on one of a polyester resin and an epoxy resin, wherein an oxygen pressure inside the closed container is not a reduced oxygen pressure.

8. The closed container containing an aqueous solution of according to claim 7, wherein said metal based layer is covered by an epoxy-phenol based varnish.

9. A packaged article, said article including a closed container with an aqueous solution of dianhydrohexitol in direct contact with an interior surface of said container, said interior surface is formed from a metal layer, and an optional varnish layer covering said metal, wherein said dianhydrohexitol directly contacts one of said layers, and wherein an oxygen pressure inside the closed container is not a reduced oxygen pressure.

10. The article of claim 9, wherein said metal comprises one of aluminum and steel.

11. A method of producing a product from a dianhydrohexitol precursor, comprising: providing a closed container of the precursor, said precursor comprising an aqueous solution of dianhydrohexitol which is in direct contact with an interior surface of the container, wherein the interior surface is formed from at least one of a metal layer and a varnish layer and wherein an oxygen pressure inside the closed container is not a reduced oxygen pressure; and recovering said stored dianhydrohexitol for producing said product.

12. The method according to claim 11, wherein said dianhydrohexitol precursor is selected from the group consisting of isosorbide, isomannide, isoidide, and mixtures of at least two of said dianhydrohexitol precursors.

13. The method according to claim 6, wherein the wall of the container is a single layer based on aluminum.

Description

EXAMPLES

(1) The following examples illustrate the benefit of the packaging method according to the invention, by demonstrating that it enables packaging of a composition of dianhydrohexitol (isosorbide in the case in point) which remains very stable over time, as evidenced by the change in pH thereof.

(2) Not only does the pH of the liquid composition of isosorbide remain stable over several months, regardless of the storage conditions, but it is even more stable than the pH of the same composition of isosorbide in solid form.

Example 1

(3) This example relates to the packaging and storage of isosorbide, in solid or liquid form, said isosorbide having been stabilized beforehand with disodium phosphate.

(4) The procedure begins first of all by manufacturing a solid isosorbide composition and a liquid isosorbide composition, in the following way:

(5) 1 kg of a solution of sorbitol at 70% of dry matter sold by the applicant company under the name Neosorb 70/02 and 7 g of concentrated sulfuric acid are introduced into a jacketed stirred reactor. The mixture obtained is heated under vacuum (pressure of approximately 100 mbar) for 5 hours so as to eliminate the water contained in the initial reaction medium and that originating from the sorbitol dehydration reaction.

(6) The reaction crude is then cooled to 100° C. and then neutralized with 11.4 g of a 50% (by weight) sodium hydroxide solution. The isosorbide composition neutralized in this way is then distilled under vacuum (pressure lower than 50 mbar).

(7) The slightly colored (light yellow color) crude isosorbide distillate is then dissolved in 2-propanol, at a temperature of 60° C., so as to obtain a solution with 75% DM. This solution is then cooled slowly, over the course of 5 hours, down to a temperature of 10° C. A recrystallized isosorbide seed is added at 40° C.

(8) The crystals are then drained in a centrifuge and washed with 2-propanol. After drying under vacuum, the crystals are redissolved in water so as to obtain a DM of 40%.

(9) This solution is then percolated on a column of granular active carbon CPG 12-40 at a rate of 0.5 BV/h (Bed Volume/hour). The decolored isosorbide composition thus obtained is then passed, at a rate of 2 BV/h, successively over a column of Purolite C 150 S strong cationic resin and then a column of Amberlite IRA 910 strong anionic resin. This solution is then treated with powdered active carbon of Norit SX+ type at 20° C. for 1 hour. The active carbon is used in a proportion of 0.5% expressed by dry weight/dry weight of solution.

(10) 0.005% of disodium phosphate (stabilizer) (dry weight/dry weight of isosorbide contained in the composition) is then introduced into said composition.

(11) After filtration, the isosorbide solution is concentrated under vacuum. The solution is concentrated until a solution with 80% dry matter is obtained. A portion of the solution is recovered in order to carry out tests 4, 5 and 6. The concentration under vacuum of the remainder of the solution is then carried out, in order to eliminate the residual water. The molten mass obtained crystallizes on cooling in the form of a massed product of large crystals which is subsequently ground to obtain a white-colored powder having a moisture content of 0.2%. This powder is recovered for tests 1, 2 and 3.

(12) These different compositions then serve to illustrate the packaging method according to the invention or according to the prior art.

(13) Test No. 1

(14) This test relates to the prior art and illustrates the packaging of the solid isosorbide composition in a “PE+Alu” conditioning. More specifically, this conditioning consists of a first inner bag (20 cm×20 cm) made of polyethylene (PE) with a thickness of 100 μm, combined with a second outer bag (25 cm×25 cm) consisting of an aluminum complex (Alu) containing 80 μm thick polyethylene covered with 8.5 μm thick aluminum.

(15) The isosorbide composition is packaged in the following manner: 100 g of the solid isosorbide composition as obtained above are introduced into the inner PE bag which is closed by sealing using an impulse heat sealer (SZ 380 model sold by Joisten & Kettenbaum GmbH & Co, Bergisch Gladbach, Germany). This bag is itself placed inside the outer bag Alu, which is then closed by sealing with the same heat sealer in order to ensure leaktightness with regard to the outer atmosphere.

(16) Test No. 2

(17) This test relates to the prior art and illustrates the packaging of the solid isosorbide composition in a conditioning consisting of “white PE BigBag Liner/alu/PET”. More specifically, this conditioning consists of a bag (25 cm×25 cm) consisting of a complex of total thickness of approximately 100 μm consisting of an inner layer made of polyethylene (PE) with a thickness of 80 μm, an intermediate layer made of aluminum with a thickness of 9 μm and an outer layer made of polyethylene terephthalate (PET) with a thickness of 12 μm.

(18) The isosorbide composition is packaged in the following manner: 100 g of the solid isosorbide composition as obtained above are introduced into the “white PE BigBag Liner/alu/PET” bag which is closed by sealing using an impulse heat sealer (SZ 380 model sold by Joisten & Kettenbaum GmbH & Co, Bergisch Gladbach, Germany) in order to ensure leaktightness with regard to the outer atmosphere.

(19) Test No. 3

(20) This test relates to the prior art and illustrates the packaging of the solid isosorbide composition in a conditioning consisting of “carbon PE+Alu”. More specifically, this conditioning consists of a first inner bag (20 cm×20 cm) made of carbon-additivated polyethylene (carbon PE) with a thickness of 150 μm, and a second, outer, bag (25 cm×25 cm) consisting of an aluminum complex (Alu) containing 80 μm thick polyethylene covered with 8.5 μm thick aluminum.

(21) The isosorbide composition is packaged in the following manner: 100 g of the solid isosorbide composition as obtained above are introduced into the inner carbon PE bag which is closed by sealing using an impulse heat sealer (SZ 380 model sold by Joisten & Kettenbaum GmbH & Co, Bergisch Gladbach, Germany). This bag is itself placed inside the outer bag Alu, which is then closed by sealing with the same heat sealer in order to ensure leaktightness with regard to the outer atmosphere.

(22) Test No. 4

(23) This test relates to the invention and illustrates the packaging of the liquid isosorbide composition in aluminum conditioning, referred to as “Alu”. More specifically, this conditioning is a 300 ml pure aluminum flask (>99.5% of aluminum). A flask of this type is sold especially by VWR under the reference 215-0261 or by Burkle under the reference 0327-0300.

(24) The isosorbide composition is packaged in the following manner: 100 g of the liquid isosorbide composition as obtained above are poured into the aluminum flask which is closed by screwing on a plastic cap equipped with an internal seal, also made of aluminum, in order to ensure leaktightness with regard to the outer atmosphere.

(25) Test No. 5

(26) This test relates to the invention and illustrates the packaging of the liquid isosorbide composition in a stainless steel conditioning, referred to as “Inox”.

(27) More specifically, this conditioning is a 355 ml 18/8 (18% chromium 8% nickel) stainless steel flask. Such a flask is sold especially by sans-BPA.com under the reference 09.01.10.01, with a Loop Inox PP5 cap.

(28) The isosorbide composition is packaged in the following manner: 100 g of the liquid isosorbide composition as obtained above are poured into the stainless steel flask which is closed by screwing on a cap, also made of stainless steel, in order to ensure leaktightness with regard to the outer atmosphere.

(29) Test No. 6

(30) This test relates to the invention and illustrates the packaging of the liquid isosorbide composition in a metal conditioning coated with an epoxy layer, referred to as “Metal Epoxy”. More specifically, this conditioning consists of a 150 ml steel flask coated with an epoxy-phenol resin.

(31) The isosorbide composition is packaged in the following manner: 100 g of the liquid isosorbide composition as obtained above are poured into the epoxy metal flask which is closed by crimping on a cover also made of steel coated with an epoxy-phenol resin using a crimper (Sertibasic 132 model, sold by SCIM, Casteljaloux, France). Such a flask is especially sold by Temaco under the reference 120619.

(32) The solid and liquid isosorbide compositions packaged according to tests 1 to 6 are placed in a ventilated oven, thermostated at the temperature of 50° C. Several conditionings per test are placed in the oven in order to monitor the change in pH of each composition over time.

(33) The change in pH of each composition over time is monitored in the following way: firstly, for each solid or liquid isosorbide composition, all the sample is extracted from the conditioning materials and is added to osmosed water in order to obtain a solution of isosorbide with 40% dry matter in osmosed water, then the initial pH of this solution is measured. The pH measurement is carried out on a pH meter of Radiometer Analytical PHM 220 brand equipped with a combined Ag/AgCl wire electrode of Mettler Toledo brand, calibrated beforehand using pH 7 and 4 buffer solutions. After a determined period of storage at 50° C., a solution of isosorbide with 40% dry matter is prepared in the same way in osmosed water for each solid or liquid isosorbide composition, then the pH is measured using the same pH meter. The results are given in table 1.

(34) TABLE-US-00001 TABLE 1 Test No. 1 2 3 4 5 6 Packaging White PE + Alu White PE BigBag Carbon PE + Alu Alu Inox Epoxy Metal Liner/alu/PET Physical form Solid Solid Solid Liquid Liquid Liquid pH 0 day 7.2 7.6 7.2 7.4 7.4 7.4 pH 1 month 3.1 3.9 3.2 7.8 7.3 7.5 pH 2 months 7.0 4.9 7.5

(35) These results demonstrate clearly that the aqueous solution of isosorbide conditioned according to the invention in an “Inox”, “Alu” and “Epoxy Metal” packaging is much more stable than the solid isosorbide conditioned in the “PE+Alu”, “white PE BigBag Liner/alu/PET” and “carbon PE+Alu” packaging.

Example 2

(36) This example relates to the packaging and storage of isosorbide, in solid or liquid form, said isosorbide having been stabilized beforehand with diethanolamine.

(37) The procedure begins first of all by manufacturing a liquid isosorbide composition and a solid isosorbide composition in the same way as for example 1, except for the fact that the disodium phosphate is replaced by 0.0025% of diethanolamine by dry weight relative to the dry weight of isosorbide.

(38) The liquid and solid compositions obtained as above then serve to illustrate the packaging method according to the invention or according to the prior art.

(39) In this example, the flasks according to the invention are the same as those described in the preceding example.

(40) Test No. 7

(41) This test relates to the prior art and illustrates the packaging of the solid isosorbide composition in a “PE+Alu” conditioning. More specifically, this conditioning consists of a first inner bag (20 cm×20 cm) made of polyethylene (PE) with a thickness of 100 μm, combined with a second outer bag (25 cm×25 cm) consisting of an aluminum complex (Alu) containing 80 μm thick polyethylene covered with 8.5 μm thick aluminum.

(42) The isosorbide composition is packaged in the following manner: 100 g of the solid isosorbide composition as obtained above are introduced into the inner PE bag which is closed by sealing using an impulse heat sealer (SZ 380 model sold by Joisten & Kettenbaum GmbH & Co, Bergisch Gladbach, Germany). This bag is itself placed inside the outer bag Alu, which is then closed by sealing with the same heat sealer in order to ensure leaktightness with regard to the outer atmosphere.

(43) Test No. 8

(44) This test relates to the prior art and illustrates the packaging of the solid isosorbide composition in a conditioning consisting of “white PE BigBag Liner/alu/PET”. More specifically, this conditioning consists of a bag (25 cm×25 cm) consisting of a complex of total thickness of approximately 100 μm consisting of an inner layer made of polyethylene (PE) with a thickness of 80 μm, an intermediate layer made of aluminum with a thickness of 9 μm and an outer layer made of polyethylene terephthalate (PET) with a thickness of 12 μm.

(45) The isosorbide composition is packaged in the following manner: 100 g of the solid isosorbide composition as obtained above are introduced into the “white PE BigBag Liner/alu/PET” bag which is closed by sealing using an impulse heat sealer (SZ 380 model sold by Joisten & Kettenbaum GmbH & Co, Bergisch Gladbach, Germany) in order to ensure leaktightness with regard to the outer atmosphere.

(46) Test No. 9

(47) This test relates to the invention and illustrates the packaging of the liquid isosorbide composition in aluminum conditioning, referred to as “Alu”. More specifically, this conditioning is a 300 ml pure aluminum flask (>99.5% of aluminum).

(48) The isosorbide composition is packaged in the following manner: 100 g of the liquid isosorbide composition as obtained above are poured into the aluminum flask which is closed by screwing on a plastic cap equipped with an internal seal, also made of aluminum in order to ensure leaktightness with regard to the outer atmosphere.

(49) Test No. 10

(50) This test relates to the invention and illustrates the packaging of the liquid isosorbide composition in a stainless steel conditioning, referred to as “Inox”.

(51) More specifically, this conditioning is a 355 ml 18/8 (18% chromium-8% nickel) stainless steel flask.

(52) The isosorbide composition is packaged in the following manner: 100 g of the liquid isosorbide composition as obtained above are poured into the stainless steel flask which is closed by screwing on a cap, also made of stainless steel, in order to ensure leaktightness with regard to the outer atmosphere.

(53) Test No. 11

(54) This test relates to the invention and illustrates the packaging of the liquid isosorbide composition in a metal conditioning coated with an epoxy layer, referred to as “Metal Epoxy”. More specifically, this conditioning consists of a 150 ml steel flask coated with an epoxy-phenol resin.

(55) The isosorbide composition is packaged in the following manner: 100 g of the liquid isosorbide composition as obtained above are poured into the epoxy metal flask which is closed by crimping on a cover also made of steel coated with an epoxy-phenol resin using a crimper (Sertibasic 132 model, sold by SCIM, Casteljaloux, France).

(56) The solid and liquid isosorbide compositions packaged according to tests 7 to 11 are placed in a ventilated oven, thermostated at the temperature of 50° C. Several conditionings per test are placed in the oven in order to monitor the change in pH of each composition over time.

(57) The change in pH of each composition over time is monitored according to the same protocol as for example 1.

(58) The results are given in table 2. As for example 1, it is observed that the aqueous solutions of isosorbide packaged according to the invention are much more stable than the solid compositions of isosorbide packaged according to the prior art.

(59) TABLE-US-00002 TABLE 2 Test No. 7 8 9 10 11 Packaging White PE + White PE Alu Inox Epoxy Alu Big Bag metal Liner/alu/PET Physical form Solid Solid Liquid Liquid Liquid pH 0 day 8.1 8.4 8.5 8.5 8.5 pH 1 month 6.5 7.5 8.3 8.3 8.2 pH 2 months 3.2 7.5 8.3 8.2 8.2 pH 3 months 3.2 7.1 6.9 7.0