DE1593253A1 - Process for the stabilization of monomeric vinylidene chloride - Google Patents

Description

Dr. Walter Bei! Alfred Hoeppener

Dr. Hans Chr.Beil ...

Lawyers "« flUg, 1300

Frankfurt a. M.-Höchst

Adeionstrasse 58 - Tel. 31 26 49

Our Kr. 12951

PITTSBUIiGIi PLATE GLASS GCMPAL ϊ Pittsburgh, Pa. V.St.A.

Process for stabilization: of monomeric »vinylidene chloride.

The present application relates to dilution of monomeric vinylidene chloride (VDO).

Vinylidene chloride is known to be an unstable compound which easily decomposes autogenously, probably about free radicals, which are under the influence of oxygen are formed.

When standing, vinylidene chloride builds up. üünlich to form unwanted color bodies. The Aboau is particularly noticeable d:. *. Nn when the vinylidene chloride is in j-egenv.art of fluid steel is stored, e.g. in btahltroniLtieln, in which it is usually transported and stored.

The treatment according to the invention improves the stability of monomeric vinylidene chloride. Thus, the vinylidene chloride treated according to the invention shows a noticeably increased color stability. The erfindun _c; s _o eiiiLu3se method is kidney sov.ohl in the raw, i ο no AuCN than at the very pure ionomers applicable. When a crude inonomeric vinylidene chloride is treated according to the invention, the monomer shows less tendency to polymerize in arisen-less physical purification processes, for example distillation.

009829/1734 -2-

BATH ORIGINAL

In the practical application of the invention, the monomeric vinylidene chloride is treated by contacting it with aqueous solutions containing silver, lapine and / or mercury ions. An aqueous ammoniacal copper (I) sulfate solution is particularly useful. Ea ^ diii example was found that crude vinylidene chloride, the $ 0 Li en long at room temperature with a same. Volume of amniotic copper-I-sulphate (2? »CuSO .: 5 H ₂ O in 5 ° NH.OH) well mixed and then filtered anu phutene-separated, stabilized with 5,000 iiles / ikillion phenol and in the presence of mild steel 2:50 at a 2er hours was .peratur supported by 5O ⁰ G, had an APHA color value of η ar 10-15 units (Pt-Go scale). Untreated vinylidene chloride gave under the same storage conditions for 100 hours an APriA Furb value of 1 μG units. An explanation of the APHA color test can be found in the £ j.ch "Standard Le" Lhods for the Examination of V / ater, Sev / age, and Industrial V. Branches "American Health Association, In. (1st edition, 195i>) »Visible at ce 87.

The iiehandluries the monomeric vinylidene chloride according to the vorlie ^ enöen Erfindan _o is best obtained by thoroughly mixing the monomers with an aqueous solution of silver, mercury or Kapfersalzen achieved. The jellies are usually used in relatively low concentrations, for example about 0.5 to 5 · 0 percent by weight, based on the weight of the acid in the solution. A coordinating ligand is preferably added to the solution in order to make the salt soluble, ie to produce a complex compound of the rietall ions contained in the solution or to stabilize the ions.

LcJi can use many kinds of copper, ^ uecicsilber, and silver stilts related. In general, any salt can be used, including the coordinating Ligands - has the desired solubility in aqueous solutions. Suitable salts include copper I salts

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009829/1734

BATH ORIGINAL '

e.g. ammoniacalic copper ferricyanide, copper I ferrocyanide, copper I hydroxide, copper I oxide, copper I sulfate, copper I carbonate, copper I cyanide, copper 1- ferricyanide, copper-I-sulfide or copper-I-thiocyanate; Copper (II) salts, e.g. copper (II) aee tat, copper (II) aü.moniumchlorid, copper (II) tetraamine sulfate, copper (II) bromate, copper (II) bromide, copper (II) chlorate, copper -II-chloride, copper-II-fort: .iat, copper-II-lactate, copper-II-nitrate, Ivupfer-II-fluorosilicate or copper-II-sulfate | », Ueccsilber-II-salts, e.g. mercury-II-acetate, CiUecksilber-II-brouiid, Il-chlorate, I-chlorate, mercury-I-aettat, ^ utcV: silver-I-formate, mercury-I-nitrate, v.uccksilbfcr-I-iluorLiliicü.t} una wilberealze, e.g. silver acetate, Silun-mov. Ι orat, t- Silver chlorate, silver fluoride, silver nitrate, syllable pptiohlorate, silver fluorosilicate and silver sulfate, oil, Kapfea-I and mercury-I ions are preferably reduced because the precipitate formed by these ions is less explosive than they are when using copper-II- o, er ^ ueclLsilber-II-ions containing wä ^ sritjen solutions, resulting Meder-Lät: t. Especially before ^ u ^ t v.eideii wä.vsri "«? ii-JLzi t-rI- Löaun ._; en.

In each case the veiv.endet ^ij : iw ^ .tu ^ tn Löcun ^ e with a coordinating Li ^ anden ve. ^ «Vv ^ t vei: en, am aie luettillionen in complex ions un.i-av. ^ Ndeln αηΰ .ie loulici ^ ^ a make. Lan can at ^ roct-t? Jihl Jü ligands veiv ^ nJen, z.3. Acetonitrile, aGiTiSt thiourea, xthylenethiourestoif, C _t . -riiä, ^ lk ^! phosphine, e.g.! iriäthylphosphin und iripropylp :: oä jiiii.,, t ^ .ine, z. ^. primary, secondary and tertiary alkanols, alkanol avalanches (where the alkyl or alkanol groups contain 1 and 5 carbon atoms), liquid or aqueous anionic, thiocyanates, e.g. 5. Sodium, potassium or A ^^ oni ^ mthiocyanate, ab. R- ! «Aturlioh every coordinating country can use the tiio .1 n: ii den: monomers

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009829/17 ^ 4 BADORfGINAt

Vinylidene chloride reacts and can easily be separated from it in phases. The coordinating ligand is generally used in relatively small amounts, e.g. about 1 to 15, rarely less than about 0.5 or more than 25 percent by weight, based on the water of the solution. The preferred group of carding ligands includes wns & riges and liquid ammonia and primary, secondary and tertiary alkyl and alkanol amines.

Lie drawing represents a flow diagram of a test facility which operates in accordance with the present invention.

ψ The heating vessel 1 in the drawing was charged with crude vinylidene chloride and an open volume of an aramoniakali copper sulphate solution. The starting solution introduced into the reaction vessel contained 2 percent by weight CuüSCL ·. 5 ή Jj and 5 percent by weight ΝΗ, ΟΗ, based on the weight of the viasser in the solution. The feed rate was about 14.4 liters of crude vinylidene chloride per hour. A three-stage container provided with a guide plate and a stirrer was used as the reaction vessel. The mixture withdrawn from the reaction vessel was passed through a 1 filter 2 to remove any precipitates which had formed in the reaction vessel. The mixture of vinylidene chloride and ammonia was filtered

Copper sulphate solution in the I-yrex phase separator 3, which was 10.16 cm in diameter, was phase-separated. The aqueous phase was oxidized by means of pressure from the phase center to the air oxidation chamber 4 ο ^θίαηΓ ^ » ⁱⁿ accordance with the reaction formula Ju ⁺ + 0— * ■ Gu ⁺⁺ copper-I-ions with air to form copper-II-ions became. The pH of the aqueous phase was measured Y.'ert in re ^ elmäesigen intervals, '!, The pn Fourth ean below 10.0 sank, the Luftoxydationskammer aqueous ammonia was added until the pH of the aqueous phase 11.0 fraud. Air was blown at a rate of 28.3 l / hr for 2 minutes every hour. introduced into the chamber.

The partially oxidized * .- ammoniacal copper sulfate solution, / from the air oxide .tion chamber 4 to the copper

009829/1734 ~ ⁵ "

BADOFHGINAL

chamber 5 pumped. This copper chamber consisted of an Oyrex tube with a diameter of 10.16 cm, the initial copper filling of which was about four feet. In this chamber the. Copper (II) ions in the solution are reduced to copper (I) ions by the metallic copper ^{according to the reaction formula Cu ++} + Gu ⁰ -> 2 0 \ x ^+. The copper ions produced in this way served to replenish the copper in the aqueous ammoniacal solution. The solution containing copper (I) ions withdrawn from the copper chamber was returned to the reaction vessel 1.

Hau vinylidene chloride from the phase separator was passed by means of pressure to a washing column 6, in which it was washed with water. This column was a 1.80 m long Pyrex tube with a diameter of 5.08 cm, at the lower end of which there was a section of a Pyrex tube with a diameter of 10.16 cm, which served as a surge pot. Any traces of the aminoniakaliscaen copper-I-sulfate solution, which might have been carried away from the phase separator 5, should be removed in the scrubber. The vinylidene chloride closed off from the ash . an ivalzium chloride dryer 7, which consisted of a 1.20 m long section of a Pyrex tube with a diameter of 10.16 cm and was filled with anhydrous (91%) calcium chloride pellets. In the dryer, the water content of the vinylidene chloride was reduced from over about 350 l'eile / toillion am to about;, u [ceile / aiillion. Kachdem the product obtained • Δ \ λϊ Distance low- and high-boiling or ^ Nian impurities by conventional distillation and kühleinricntungen 8, was passed 9 and 10, were obtained generally a product with a purity of over 99.9? Έ.

The monomeric vinylidene chloride used in the examples was used as a Zv-ischenproduukt in the manufacture of 1,1,1-triehlorethane according to the USA patent specification; 065 280 manufactured. D-.s used in the present examples crude monomeric "vinylidene chloride was according to the example of

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009829/1734 BAD ORIGINAt.

U.S. Patent 3,065,280. Thus, the monomeric vinylidene chloride used in the examples was prepared by adding ethylene under Formation of 1,1,2-trichloroethane and evolution of hydrogen chloride has been chlorinated with elemental chlorine. Dieees 1,1,2 ~ trichloroethane was then formed with crude vinylidene chloride (1,1-dichloroethylene) dehydrochlorinated.

The test facility ran 24 hours per lug for about 6 days. The operations were running continuously and the plant were only minor checks and "cures ψ interrupted. In this period were 1095 kg Rohee vinylidene introduced into the test facility. 1073 kg vinylidene were after copper treatment, ie, before being transferred to one of the Destiallationsapparate won . Subsequently, the vinylidene chloride was BAW for the removal of low. high-boiling organic substances duroh a distillation column 8 for leichtaiedende substances and 9 directed to a distillation column for schwersiedenae substances "from the cooler 10 was obtained about 1,049 kg of purified vinylidene chloride. the condense monomeric vinylidene chloride was treated with 500 25 parts / million parts of paramethoxyphenol stabilized, one part of the stabilized monomer v. 'Was stored in a stainless steel container. Another part was stored in conventional oil drums with a capacity of 200 liters, which had been thoroughly cleaned beforehand.

Ls found that the color stability of the monomer is improved if the Speucner containers are kept as clean as possible. An appropriate cleaning process for a steel drum is the drum at least Rinse thoroughly three times with about 8 liters of condensed steam. Then the drum is filled with live steam au clean and dry thoroughly.

The stored vinylidene chloride was analyzed weekly. The color stability was extremely good. So ze Lg-

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009829/1734

BATH ORIGINAL

The vinylidene chloride stored in the stainless steel container had an APHA color value of only 15 on the 6th analysis. Similar values were found in the analyzes in the cleaned ones Vinylidene chloride stored in steel drums.

The inventive method can of course in a carried out a large number of different embodiments will. For example, the treatment explained in the example as a continuous operation can also be discontinuous if necessary are executed. The solution should preferably have a pH value above at least about 7, preferably between about 9 and 11, rarely above 11.5. It has been found suitable to use the vinylidene chloride an approximately equal volume of the aqueous phase to I.

treat. Useful results can also be used if other ratios to the aqueous solution are used. So the vinylidene chloride z..l. with one u. significantly smaller volume of the aqueous phase, ie with only about 3 #, rarely less than 2% and preferably about 20 to about 150 fi are brought into contact. Although the treatment of vinylidene chloride with a volume of the aqueous solution that is much larger than the same generally has the consequence that excessively large bends in the aqueous phase are recycled, substantial excesses, for example up to several 100%, can often be used. The desired concentration of copper, silver or vuecksilüerionen in the aqueous phase iat verbouieJt-n, but should average between about 1 and 4, rarely vt: .i _o er alü etv.a 0.3 or more than about 5 percent by weight, be-do ^ en on the weight of the solution.

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009829/1734 BAD ORiGINAt '

Claims (1)

Claims 1) Process for stabilizing monomeric vinylidene chloride, characterized in that the monomeric vinylidene chloride with a silver, mercury and / or Lupferionen-containing aqueous solution brings into contact. 2) The method according to claims 1, characterized in that the m: .n the treatment with a silver, mercury I- and / or an aqueous solution containing copper ions. 5) Method according to ^ nipruch 1 and 2, characterized in that that an aqueous treatment solution is used which also contains a coordinating ligand, unc the monomeric vinylidene chloride is obtained from the ischoOig. 4) The method according to claim 3, characterized in that ε one _{uses a jehandlun o} slösung which, as coordinating ligands, is aqueous or liquid ammonia or priLvires, secondary or tertiary alkyl or .alkanolamines ψ contains. 5) The method according to claim 35, characterized by ^ ekennzeicnnet, d: -fcs one keeps the pH of the aqueous solution but 7. 6; Method according to claim 1 bit; 5 »characterized by d ^ ss the monomeric vinylidene chloride thoroughly with a aqueous solution of a copper salt mixes which is sufficient to stabilize the copper ion contained in the aqueous solution Contains amount of coordinating ligand, and the monomeric vinylidene chloride from the mixture gev.inn. -9- 009829/1734 BAD ORtQINAL 7) Method according to claim 6, characterized in that that the aqueous solution used is about 0.2 to 5 percent by weight Copper salt and about 1 to 15 percent by weight of Am.; Ionium hydroxide, based on the weight of the water contained in the solution. 8) Method according to claim 1 to 7, characterized in that the monomeric vinylidene chloride and the silver, Aqueous solution containing mercury and / or copper ions Put the mixture in a heating vessel and remove it of solids through a Piltriervorrich-üung sends, then the filtered mixture in a phase separator conducts, in which the aqueous phase is removed and returned to the fitness vessel, and the monomer Vinylidene chloride from the phase separator wins. y) Method according to claim 8, characterized gekennaeicnnet, that the vinylidene chloride obtained from the phase separation device washes to remove the remaining aqueous phase. 10) Method according to claim 91, characterized in that that crude monomeric vinylidene chloride is used as monomeric vinylidene chloride and this is used after washing Removal of organic contaminants passes into a distillation device. 11) method naoh claim 1 to 10, characterized in that that an aqueous ammoniacal solution of copper-I-sulfate is used as the treatment solution and this solution leads from the phase separation device into an air oxidation chamber, in which the copper ions are oxidized to copper (II) ions air is passed through the solution, the aqueous solution from the air oxidation chamber au a chamber filled with copper metal, in which the copper-II-ions and the copper are converted into copper-I-ions and the aqueous solution is returned from the copper-filled chamber to the reaction vessel. -10- 009829 / 1.734 BATH ORIGINAL 12) The method according to claim 11, characterized in that one daυs the aqueous solution in the chamber for Luftoxydations .Huirechterhaltung a pH of about 7 with ammonia liber: added. PITTSBüK & fl PLftl'i. GIu.ob COLPAHY IjU * Lawyer 009829/1734