EP1881969A1

EP1881969A1 - Method of storing and transporting vinylene carbonate

Info

Publication number: EP1881969A1
Application number: EP06724704A
Authority: EP
Inventors: Reinhard Langer
Original assignee: Saltigo GmbH
Current assignee: Saltigo GmbH
Priority date: 2005-05-12
Filing date: 2006-05-04
Publication date: 2008-01-30
Also published as: JP2008540468A; KR20080008420A; CN101175744A; US20090131687A1; WO2006119908A1; DE102005021965A1

Abstract

Method of storing and transporting vinylene carbonate, characterized in that the vinylene carbonate possesses a stabilizer content of less than 100 ppm, has a degree of purity of 99.9% to 99.99999%, and is in the solid aggregate state.

Description

Process for the storage and transport of vinylene carbonate

The present invention relates to a process for the storage and transport of vinylene carbonate (VC).

Vinylene carbonate is an important intermediate for the manufacture of chemicals, pharmaceutical products, pesticides and, in particular, for polymers, paints and battery electrolytes.

Vinylene carbonate is prepared by known methods by splitting off hydrogen chloride from chloroethylene glycol carbonate by means of tertiary amines, in particular triethylamine.

Chloroethylene glycol carbonate (CGC) is obtained by radical chlorination of ethylene glycol carbonate using chlorine or sulfuryl chloride.

This synthesis was first published in 1953 by Newman and Addor (JACS, 1953, p. 1263; JACS 1955, p. 3789).

Ethylene glycol carbonate (GC) was riert photochlo- means of ultraviolet light at 60-70 ⁰ C in substance and the resulting CGC purified by vacuum distillation.

VC received Newman and Addor by elimination of medium triethylamine in boiling ether, the mixture being heated overnight.

The isolation was carried out by filtering off the triethylammonium chloride and subsequent distillation, which yielded a crude VC with 59% yield, which had to be purified by further distillation.

JP 2000/026449 describes the elimination in high-boiling solvents (bp. 170-300 ⁰ C). Explicitly reacted with triethylamine in dibutyl carbonate for 20 hours at 50 ⁰ C. After filtering off the ammonium chloride and distilling off excess triethylamine, crude VC is isolated by simple distillation. To remove traces of the amine, the VC is passed over a silica gel column. Finally, a fine distillation is carried out. The chlorine content of the VC thus obtained is given as 29 ppm, while comparative samples contain> 3000 ppm. The yield is 56%.

DE-A 19 955 944 claims the elimination in GC as solvent (bp 243-244 ° C). CGC is charged to GC and reacted in 1.5 hours by addition of triethylamine at 60 ⁰ C. After distilling off. Excess triethylamine at 40 ⁰ C and evaporation over a Dünnschich- ter at 100 ⁰ C is obtained with 73% yield a colorless mixture of VC and GC. About the purity is not specified. The reactions of CGC in the liquid phase, after filtering off the salts and simple distillative separation from the solvent and other impurities, give a crude vinylene carbonate contaminated with residues of chloroacetaldehyde, chloroglycol carbonate, dichloroglycol carbonate and other partly chlorine-containing organic compounds.

Johnson and Patton described in JOC, 1960, p. 1042, the reaction of CGC on solid beds of CaSO 4 catalysts in the gas phase at 250 ⁰ C and 50-60 Torr.

DE-A 1135452 describes the elimination of HCl from CGC at 300-400 ⁰ C. The CGC is passed in gaseous form over an inert support material which with elements of L, JJ. or VIYY. Subgroup of the periodic table or their salts or oxides is occupied. Preferably, the chlorides of iron, cobalt, copper, particularly preferably cadmium chloride are used. Suitable support materials are pebbles and silicates with grain sizes of 4 to 8 mm.

The catalysts are operated as a stationary bed at atmospheric pressure or reduced pressure and a temperature of 270 to 450, preferably from 300400 ⁰ C.

The gas phase process for producing vinylene carbonate, after simple distillation, gives a crude vinylene carbonate that is very similar to the liquid process in terms of impurities.

In terms of distillative cleaning effort, the information in the literature are inaccurate, so that the effort was driven in each case and the yield losses can not be estimated by the cleaning.

High purity of the VC, especially for the applications of polymerization and additive for battery electrolytes, is of great technical importance.

It is described in US Pat. No. 2,873,230 that VC, prepared by the method of Newman and Addor, can not be sufficiently purified even with an 80-column column in order to be copolymerized with vinyl acetate and that insufficient molecular weights are achieved in homopolymerization. Chlorine contaminants are held responsible.

Huang et. al. describe in Chin. J. PoIm. Be. (1990) 8 (3), 197-203 that VC is prepared by the method of Newman and Addor, after its isolation by filtration and distilling off the solvent for 1 hour with about 4% NaBH4 at 64 ° C and then stirs one Subject to fine distillation. This procedure must be repeated to obtain discoloration-stable, well-polymerizable material. Both references are not exactly on the content of impurities, which remained in the pure VC. Losses due to the isolation procedure are also open.

GB-A 899 205 describes the purification of VC produced by Newman and Addor by repeated melt crystallization. In order to obtain high molecular weight polymers one must use VC with a melting point greater than 21 ° C obtained by quadruple crystallization. Again, not directly on the purity of the VC is received, as well as the whereabouts of the mother liquors. Since the VC was prepared as described in JACS 75, 1263 (1953), distilled VC was used in the crystallization.

Zief and Ruch describe in the Journal of Chemical Education (1963, Vol. 40, p. 351-2) the cleaning of VC by zone melting. A monomer with a melting point of 22 ° C and a chlorine content of 1-1.8% achieved after a single zone melting a chlorine content of 500 ppm, after 3 more passes through the zone melting apparatus, the VC reached a chlorine content of 50 ppm. The more contaminated the VC, the more zone melting runs the material requires, therefore the authors consider upstream distillation to be useful.

JP 2002-322171 describes the combination of distillation and crystallization for the purification of VC. For crystallization, solvent mixtures of an aromatic component and an aliphatic hydrocarbon are claimed. The yield via distillation and crystallization in the examples is 60 and 83%. The purity is above 99.95%. Impurities of ethylene glycol carbonate of 400 and 25 ppm and chloride contents of 15 ppm remained in the VC.

In the applications for purification by crystallization, working either with larger amounts of solvents, or the crystallization process must be repeated several times to achieve high purities.

When working with solvent, the VC must finally be distilled again, you want to remove considerable residues of solvent from the VC.

Also during transport and storage of VC, a stabilizer must always be added to prevent the decomposition of VC.

It should be noted that the analytical methods for determination of purity in the literature are not described in detail, so that the purity data are not unique.

The object of the invention is to provide a method for storage and transport of vinylene carbonate. It has surprisingly been found that VC can advantageously be stored and transported without decomposition if it is present in solid form in a high degree of purity.

The invention relates to a process for the storage and transport of vinylene carbonate, in which the VC has a stabilizer content of less than 100 ppm, preferably less than 10 ppm, and a purity of 99.9 to 99.99999%, preferably 99.99 to 99.9999% and is in the solid state.

Advantageously, this high-purity VC is obtained by using the VC

a) at a temperature in the range of 25 to 180 ⁰ C with an organic compound having at least one amidic hydrogenated hydrogen bond in contact,

b) if necessary, any precipitated solid is filtered off,

c) distilling the remaining solution through a column and

d) from the distillate by crystallization receives the purified VC.

Organic compounds containing amidic nitrogen hydrogen bonds in the context of the invention are all aliphatic and aromatic carboxylic acid amides containing one or more of the following functional groups of the following formula (I)

with R =H, C ₁ -C ₁₀ -alkyl or cycloalkyl, C ₆ -C ₁₀ -aryl,

have or ureas of the following formula (TT)

with R, R "and R" the same or different = H, Q-Cio-alkyl or cycloalkyl, C ₆ -C ₀ -aryl, ureas are preferably used.

Preference is given to organic compounds having amidic nitrogen hydrogen bonds from the group formamide, methylformamide, acetamide, methylacetamide, ethylacetamide, phenyl acetamide, adipamide, benzoic acid amide, phthalic acid diamide, propionamide, dimethylurea, diethylurea, diphenylurea, urea. Dimethylurea, diethylurea, diphenylurea are particularly preferably used. Very particular preference is urea.

The thermal treatment in step a) is carried out with stirring at temperatures between 25 and 180 ^° C., preferably between 60 and 160 ^° C., more preferably between 90 and 140 ^° C.

Relative to the vinylene carbonate, 0.1-30% by weight, preferably 1-10% by weight, more preferably 2-6% by weight, of cleaning substance is added.

The addition of the organic compound with at least one amide nitrogen compound can be carried out in the presence or without the addition of solvents. Examples of suitable solvents are dimethylacetamide, N-methylpyrrolidone (NMP), dimethylformamide and DMSO.

After the thermal treatment and the filtration of a possibly precipitated solid, the vinylene carbonate is distilled off from the residue in step c). This can be done as a batch distillation from a container via a column having at least 10, preferably at least 20, more preferably at least 30 trays.

Column internals are all possibilities known to those skilled in the art, e.g. Bubble cap trays, sieve trays, further packed beds such as, Raschig rings, Pall rings, Berlsättel, also cross-channel structures such. the packs of Sulzer and Montz.

The low-boiling precursors of the fine distillation obtained by the process according to the invention are advantageously collected and distilled separately for the low-loss removal of those low boilers, the VC thus recovered being recycled for the thermal treatment in step a) and / or fine distillation in step b) ,

The VC thus obtained is subjected to melt crystallization in the process according to the invention in step a) with a content of between 99.0 and 99.99, preferably between 99.5 and 99.9%.

The melt crystallization can be carried out in industrial plants, as are known in the art; to name in particular tube bundle crystallizer.

The VC after isolation in very high purity, with residual chloride content <10 ppm.

The mother liquor obtained in the crystallization can be recycled directly into the distillation in step c) and / or thermal treatment in step a). Unstabilized pure VC tends to polymerize, therefore it is marketed with stabilizers such as BHT.

The purer the monomer, the more sensitive it is given by unwanted polymer formation.

It has surprisingly been found that such highly pure VC can be stored unaltered in the solid state over a long time without change.

The storage and transport of high purity, stabilizer-free VC therefore takes place at a temperature between -200 ⁰ C and +20 ⁰ C, preferably between 0 and 15 ⁰ C instead.

Example: Production of solid VC (high purity):

The distillation apparatus consisted of an oil-heated 15L flat bottomed pot with anchor stirrer, column, reflux divider, condenser, and a constant vacuum device. In front of the vacuum pump was a cooled to -78 ° C cold trap. Flush pot, column, reflux condenser and condenser were made of glass, the anchor stirrer made of Teflon.

The column had a 1500 mm long Sulzer DX package of Hastelloy C with a diameter of 50 mm. Packages of this type have separations between 15 and 30 trays per meter.

The apparatus was always inertized with nitrogen before and after charging and before operation.

As a starting material was used by a pre-distillation without column substantially only free of polymeric impurities crude VC.

This crude VC was about 97% and had an organic and inorganic chlorine content of about 0.5% to 1%.

The gas chromatographic analysis was carried out by means of an HP 6890. A 50-meter-long CP-SiI 8 CB with an ID of 0.53 mm and a FD of 1.0 μm was separated.

Carrier gas was nitrogen at a pre-pressure of 5 psi. The injector was operated with a flow of 138 ml / min and a split of 30/1. Injected was 1 μL of VC pure.

The injector temperature was 220 ⁰ C, the detector temperature 320 ⁰ C. The temperature program started at 50 ⁰ C, heated at 5 ° C / min to 25O ⁰ C.

Evaluated according to the standard% method.

Example 1 (treatment with urea):

12060 g of crude VC were mixed with 200 g of urea and stirred under nitrogen at 140 ⁰ C for 2 hours. After cooling to about 30-40 ⁰ C, 235 g of solids were filtered, transferred 11743 g liquid in the above-described distillation apparatus and mixed with 1000 g of NMP.

The mixture was heated at about 35 mbar pressure to reflux and then distilled off at a reflux ratio of 30/1 forerun. Within 2.5 hours, about 160 g of distillate were obtained, so that, according to GC analysis, 96% consisted of VC. In the following 3.5 hours, about 400 g of a distillate that consisted of 97.5% of VC, followed by about 470 g of distillate with 99.4% VC content, which distilled over in 2.5 hours.

Now the main run was taken off with a reflux ratio of 5/1. In 26 hours about 9600 g of a 99.9% VC distilled over that had a chlorine content below 50 ppm.

There remained about 1100 g of swamp back, with a VC content of less than 0.5%.

The cold trap had remained practically empty.

The mass balance was practically quantitative, 93% of VC was found again.

84% of the vinylene carbonate was accumulated in the main fraction.

Example 2 (crystallization in static crystallizer):

The crystallizer consisted of a 400 mm long thermostated glass tube with an inner diameter of 30 mm. At the lower end, a perforated disc for fixing the crystals and a drain cock for the mother liquor was attached. Under the stopcock there was a argong flushed bill of exchange. At the upper end of the gas phase could be replaced by purging with argon, also passed a coolable plastic fingers into the interior, by means of which the crystallization could be initiated targeted.

302 g of the distillate from Example 1 were felt in the crystallizer and displaced the gas phase by purging with argon. The vinylene carbonate was cooled down with a 19 ° C oil circuit. Then, by cooling the cold finger, the crystallization was started and allowed to run for 4 hours.

A rapid spreading of a crystal front from the cold finger over the entire heat exchanger surface is observed. Then the crystals grew strikingly compact inside.

After 4 hours, by opening the tap at the lower end, first the liquid under the perforated plate in the uncooled part of the raw material, then the mother liquor is discharged and collected separately. Then the original was changed again and with a tap open in 1 h with a linear Ramp the oil circuit warmed to 22 ⁰ C and held for a further hour at 22 ⁰ C, whereby the crystals are cleaned by sweating. Finally, the main fraction was melted at 3O ⁰ C in a further template.

The educt was about 99.9% pure, had a chlorine content <50 ppm and a water content of about 100 ppm. 24 g of feed were collected, with a content of VC of 99.87%, a chlorine content of about 110 ppm and a water content of about 230 ppm.

It incurred 56 g of mother liquor, with a content of VC of 99.8%, a chlorine content of 160 ppm and a water content of 330 ppm.

The sweat weighed 35 g, had a content of 99.9% VC, 70 ppm chlorine and 110 ppm water.

The product melt weighed 187 g, had a 99.99% VC content, was 3 ppm chlorine, and contained 10 ppm water.

Mother liquor, flow and sweat can be recycled directly into the urea treatment or the distillation and are thus no loss.

Example 3 (Storage of VC):

Samples of vinylene carbonate purified according to Example 2 was unstabilized with exclusion of light as a liquid at 20 ⁰ C and stored in crystalline form at 5 ° C.

a) Comparative experiment:

The unstabilized vinylene carbonate samples show weak to strong yellowing and faint turbidity after 70 days. The salary, measured with ISTD much up to 96%. Unstabilized, high-purity vinylene carbonate in the liquid state is not storage-stable.

b) according to the invention:

The samples stored at 5 ° C in the solid state were all colorless and clear even after 365 days after melting. The analyzes showed no changes in quality. Unstabilized vinylene carbonate is storage stable in the solid state!

Claims

claims

1. A process for the storage and transport of vinylene carbonate, characterized in that the vinylene carbonate has a stabilizer content of less than 100 ppm, and a purity of 99.9 to 99.99999%, and is present in the solid state.

2. The method according to claim 1, characterized in that the vinylene carbonate at a temperature between -200 ⁰ C and +20 ⁰ C, stored or transported.