JPS6094929A - Separation and recovery of brominated acenaphthylene condensate - Google Patents

Abstract

PURPOSE:To obtain the condensation product of the titled compound with simple operation, in high recovery, in powdery form, from the solution of the compound obtained by the bromination, condensation and dehydrobromination reactions of acenaphthene, by carrying out the reprecipitation using a 5-9C saturated aliphatic hydrocarbon as the poor solvent. CONSTITUTION:A solution of the brominated acenaphthylene condensate having the units of formula I and formula II (n and n' are integer of 1-5) as the constituent elements and obtained by the bromination, condensation and hydrobromina- tion reactions of acenaphthene is added to a 5-9C saturated aliphatic hydrocarbon (preferably pentane, hexane, cyclohexane, heptane, octane or 2,2,4-trimethyl- pentane) to effect the reprecipitation of the condensation compound. The amount of the alcohol is usually 1-20pts.vol., preferably 2-10pts.vol. based on 1pt.vol. of the above solution. The condensation product useful as a flame-retardant and anti-radiation agent for various inflammable resins can be separated and recovered by this process in the form of powder suitable for handling and rolling.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for separating and recovering a brominated acenaphthylene condensate as a powder from a solution obtained in its production process.

Brominated acenaphthylene condensate (hereinafter referred to as Con-BACN)
1) is a compound with excellent flame retardancy and radiation resistance, and has the property of making the resin flame retardant and radiation resistant when blended with various flammable resins. In addition, since there are double bonds in the molecule, it is possible to graft it onto resins by subjecting it to free radical generation treatment, and since it is a condensate, it has excellent compatibility with resins, so it can last for a long time. It is attracting attention as a compound that can maintain stable flame retardancy and radiation resistance. (Unexamined Japanese Patent Publication No. 56-1.22862)
An object of the present invention is to provide a method for separating and recovering CO11-BACN Y powder from a solution containing CO11-BACNχ.

Con-BACN as referred to in the present invention is a compound containing one or more bromines in the aromatic ring. Formally, brominated acenaphthene undergoes a Sliedergraph reaction and is synthesized.
Condensation degree is 2 or more, and it becomes a polymorph of H, followed by a dehydrobromination reaction, and becomes Con-BACN. That is,
General formula mark or (・mar) (in the formula, n and n' are 1 to
It is a condensate consisting of a unit bi component represented by an integer of 5), and its bonding mode is an intermolecular bond between the benzylic carbon of acenaphthylene and the aryl carbon of acenaphthylene. The bonding point is, for example, 1 (or 1 (or 2), 6'-).Those having a degree of condensation of 3 or more are those in which the constituent units are increased by any of such bonds.

The condensate as used in the present invention refers to a condensation product having a degree of condensation of 10 or less and having excellent compatibility with resin.

Con-HACN is generally produced by bromination, condensation and dehydrobromination reactions of acenaphthenes.

That is, acenaphthene is brominated and condensed for 7 times in a halogenated hydrocarbon solvent in the presence of a Lewis acid catalyst by adding bromine, and the resulting halogenated acenaphthene condensate is dehydrobrominated with a base such as caustic potash-methanol. Produce it by performing 7 reactions. The dehydrobromination reaction is carried out in a base-inert solvent such as caustic potash-methanol, ie, a halogenated hydrocarbon or aromatic hydrocarbon solvent. Therefore C
on-BACN is obtained as a solution of halogenated or aromatic hydrocarbons. From the Con-BACN solution obtained through these manufacturing processes, Con-
Possible methods for separating and recovering BACN include (1) evaporating the solvent from the Con-BACN solution and (2) adding the Con-BACN solution to a poor solvent to collect the precipitate. But (1)
In the method described above, Con-BACN is solidified into a resinous state, and Co
Since n-BACN is obtained as a powder, it is difficult to handle.

In addition, although this resinous Con-BACN can be put to practical use as it is, a small amount of solvent remains in Con-BACH and is relatively difficult to remove.
The melting point of on-BACH is 50°C to 80°C, which is 50°C to 70°C lower than that of powder, and when the compound is mixed with a resin on a roll, it may cause roll adhesion, and processing and processing due to thermal decomposition of the solvent may occur. It has disadvantages such as poor workability, such as corrosion of the molding machine.

Therefore, the solvent in Con-BACH is completely removed and C
If on-BACH could be made into a powder with a high melting point, it would be extremely advantageous in terms of handling and roll mixing work.

In the method (2), a method is known in which Con-BACN is added to acetone, which is a poor solvent for dissolving Con-BACN, and then reprecipitated and recovered as a powder. (Y, Morita
andM, Had<iwar; I, J, Appl'
, Polym, Sci, 273329 (1982)
) However, according to this method (J)rxl-13AcN
Since Con-BACN dissolves in acetone to some extent, the Con-BACN solution obtained by the reaction is recovered.
Pre-concentrate followed by cold acetone (0 to -10°C)
It requires a complicated operation of adding it to the liquid and re-precipitating it. Moreover, the recovery rate of Con-BACN is also low.

The present inventors recovered eon-B as Con-13ACN Y powder by a simple operation using a reprecipitation method using a poor solvent.
As a result of searching for various types of poor solvents in order to increase the recovery rate of ACN, we found that when using a partial alcohol of a saturated aliphatic compound having 3 to 5 carbon atoms, it was possible to recover Con with a relatively simple operation and a high recovery rate. -13AcN 'Taken as Pt powder'
- I discovered what I could do and filed a patent application.

According to this method, these solvents are used as a d'''I liquid after separating the powder, and the aliphatic acycols, which are the reprecipitation solvent, are combined with the halogenated hydrocarbons or aromatic hydrocarbons and the reprecipitation solvent. When this recovered mixed solvent is used directly in a reaction, the reaction system becomes heterogeneous due to the influence of the poor solvent, and the viscous liquid separates into layers before the reaction product is produced. It forms a layer on the reactor wall and stirrer, and solidifies over time, making the reaction and subsequent separation operations difficult.Also, when these alcohol-containing halogenated hydrocarbon solvents are used in bromination and condensation reactions, This causes side reactions and results in impurities of unknown structure being mixed into the reaction product.In order to avoid such problems, there is a method of separating the recovered mixed solvent by distillation and reusing it. It is possible, but
In this case, it is impossible to separate the halogenated hydrocarbon or the mixture of aromatic hydrocarbon and aliphatic alcohol by mere distillation because they are both azeotropic. Although it is possible to remove alcohol, which is a poor solvent, as much as possible by azeotropic distillation and reuse it in the reaction with halogenated hydrocarbons or aromatic hydrocarbons, which contain less alcohol, to avoid troubles in reaction and separation operations. This method is undesirable because the solvent recovery efficiency is poor (it is not economical) and because it is impossible to avoid the generation of impurities due to side reactions, it is not possible to obtain a product of excellent quality.

The present inventors improved the above-mentioned drawbacks and produced Con-BACN from the Con-BACN solution obtained from the manufacturing process.
The purpose is to search for a poor solvent that can be precipitated and separated as a Y powder, preferably a poor solvent that has a high recovery rate as a powder (and that allows easy separation of the solvent of the Con-BACN solution and the poor solvent). Through research, we have arrived at the present invention.That is, the present invention involves bromination of acenaphthene.

Con-BACN produced by condensation and dehydrobromination reaction
By adding a solution of Con-HACN to a saturated aliphatic hydrocarbon having a carbon number of 5 to 9, Con-HACN 5 powder can be recovered at a relatively high recovery rate, and these saturated aliphatic hydrocarbons can be Because it does not azeotrope with halogenated hydrocarbons and aromatic hydrocarbons, which are the solvents of BACN solution,
After re-precipitation, the present invention was completed based on the discovery that it can be easily separated by distillation.

In this way, the present invention allows C0n-BACN
As part of the process, it provides a method for precipitating the powder from a solution and separating and collecting it.

A detailed explanation of the present invention follows.

Co n-l: 1A obtained in the 5g production process according to the present invention
The organic solvent of the cN solution refers to a good solvent that dissolves Con-BACN, and a halogenated hydrocarbon or an aromatic hydrocarbon that is inactive in the dehydrobromation reaction is selected.

For example, carbon tetrachloride, chloroform, methylene chloride, ethylene dichloride, ethylene dipromide.

Chlorbenzene, benzene, toluene, xylene.

You can ask for things like ethylbenzene. Also Co
The concentration of the n-13ACN solution is not particularly limited, but is usually 5.
~70% by weight is used.

From this Con-BACN solution, Can-BACN
In the method of the present invention, during the k separation and recovery, the solution yC
A reprecipitation method is employed in which on-HACN is added to a poor solvent and precipitated.

The poor solvent used in the method of the present invention has 5 carbon atoms.
to 9 saturated aliphatic hydrocarbons, which may be linear, monobranched or cyclic (e.g. evahentane, hexane, cyclohexane, methylcyclopentane, 2-methylpentane).

3-methylpentane, 2,2-dimethylbutane.

2.3-dimethylbutane, hegetane, methylcyclohexane, 2-methylhexane, 3-methylhexane, 2,
3-dimethylpentane, 2,4-dimethylpentane 1.
Octane, 2,2.3-trimethyl, 2,2.
4-t') Melpentane, ethylcyclohexane, nonane, etc. can be mentioned. Pentane, hexane, and cyclohexane having 5 to 8 carbon atoms from the viewpoint of industrial availability and economy.

Hegetane, octane or 2,2,4-trimethylpentane are practically preferred. These may be a mixture of two or more types. Aliphatic hydrocarbons with a carbon number of 4 or less have a low boiling point (difficult to reprecipitate at room temperature and under pressure), whereas aliphatic hydrocarbons with a carbon number of 10 or more have a high boiling point of 170°C or higher (the resulting powder drying etc. is not easy.

Furthermore, the aliphatic hydrocarbons having 5 to 9 carbon atoms according to the present invention are advantageously free from any halogenated hydrocarbons or aromatic hydrocarbons, and therefore can be easily separated by distillation and reused. Is possible.

The amount of these saturated aliphatic hydrocarbons used is
The amount used is 1 to 20 times, preferably 2 to 10 times, the volume of the on-BACN solution. If the amount of saturated hydrocarbon is less than the equivalent volume of Con-BAGN solution, use Con
There is a drawback that the recovery rate of -13AcN is low, and if the recovery rate is 20 times or more, there is no problem with reprecipitation itself, but it is not economical. Co
The reprecipitation of n-BA(,:H is carried out by adding a Con-BACN solution into the aliphatic hydrocarbon, and it is preferable that stirring is performed at that time. Con-1ACN
When added to these poor solvents, the compatibility between the solvents increases
Due to its excellent dispersibility, Co
Con-1' where precipitation of 13AcN powder occurs
1 Since the good solvent remaining in ACN can be efficiently extracted,
), efficient precipitation of Con-BACN becomes possible.

Furthermore, since the obtained crystals are obtained as fine powder, crushing after drying is not necessary.

Adding eon-1 (ACN m) to each of these girls-3'
- The temperature during filtration is not particularly limited as long as it is below the melting point of Con-BACH, but room temperature is usually sufficient.

The precipitated Co n-BACN powder can be separated by a conventional method. For example, gold can be separated by centrifugation, suction filtration, spray drying, etc.

As is clear from the above description, by implementing the method of the present invention, the C on obtained from the manufacturing process
-Con-BACNt from HACN solution with simple operations
It can be separated as a powder with a relatively high recovery rate, and since the poor solvent of the present invention does not form an azeotrope with the reaction solvent,
-BACN crystal separation (1-FJ) The mixed solvent can be separated and recovered individually if necessary by distillation, and each can be reused, making it possible to economically produce Con-BA(,IN). In addition, Con-13ACN &?, which can be obtained according to the present invention, is a fine powder and is also made into a resin and has a higher melting point than Con-BACN.・Easy to insert, insert 1 and σ)
Excellent roll workability when rolls are mixed up.

The following is a more detailed explanation using examples. I'Jf force t1
The present invention is limited to these embodiments.
・.

Example 1 Acenaphthene 2319, ferric chloride 18g and 7 carbon chloride 2. 1, and 4α at 25°C. To this solution, 43 kg of bromine and 38 liters of carbon tetrachloride were added dropwise over 5 hours. Eyebrows up to 55°C after instillation.

The color of the warm bromine did not disappear when it was heated for 15 Y. Insoluble matters in the reaction solution were removed by filtration, and the reaction solution was thoroughly washed with water, and then potassium hydroxide IQ8g'Y methanol 0.0% was added under heating to reflux.
45 lfc Melted liquid 7111 was added dropwise, and
Allowed time to react. After cooling the reaction solution, potassium bromide Yi
Filter and remove methanol? The residue was distilled off and washed three times with water to obtain 2.71'f of a Co-based BACN 470, 5-carbon tetrachloride solution. As a result of the analysis, (the given Con-BACN has a bromine content of 67%, and the degree of condensation determined by gel-no-merization chromatography is 33% below dimer, 43% trimer, 4-8% From this Co11-BACN carbon tetrachloride solution, 94 fl of Con-BACN Y was obtained.
A solution of 541 was used for the next reprecipitation. The following Con-BACN solution was added dropwise into i-octane 2.2) under stirring at room temperature over 30 minutes. Precipitation of fine powder occurred simultaneously with the dropping. After dropping, stirring was continued for another 10 minutes to completely precipitate the powder. Then, the precipitated Con-BACNwF was separated, and the obtained powder was dried at a temperature of 75°C. melting point 12
Reddish-brown powdery Con-BACN that exhibits a temperature range of 6 to 147°C
7 B, 0.9 'a' f). Con-BAe
The recovery rate of Con-1-3ACN from N carbon tetrachloride solution corresponds to 83.0. Next, the P solution was distilled, and carbon tetrachloride and i-octane were separated and recovered with a purity of 98% or higher. No problems were observed when these were reused in the next reaction or reprecipitation. .

Example 2 l f- produced as in Example 1 in n-hexane with stirring at 21 °C.
('', on-HA (', N '11 Q 4 Q containing carbon tetrachloride solution 015417 was added dropwise at room temperature over 30 minutes.

Precipitation of fine powder occurred simultaneously with the dropping. After dropping and stirring for 10 minutes, it was separated and dried to give a melting point of 126-147.
Reddish brown powdered Con-BACN at °C 76.59
I got k.

Con-BACN from carbon tetrachloride solution
The recovery rate of CN corresponds to 81.4%.

Example 3: 2.2 l'lf of n-pentane at 15°C: Into the medium while stirring with a blade, the C o n-BACN produced in Example 1 was added.
IN tetrachloride containing 94El of dissolved FE 0.54 l
Con-BAeN reprecipitation 1-+, H7, was carried out by dropping Y. The operation was carried out according to Example 2, and the melting point was 125-14.
Can-BACN reddish-brown powder at 7°C 71.9.
9 I got Y. Co from Con-BACN carbon tetrachloride solution
The recovery rate of 'n-BACN corresponds to 76.5 cases.

Example 4゜acenaphthene 92.6.9 and 2.2'-azobisisobutyronitrile 2. (1) was added to 280 ml of carbon tetrachloride and heated under reflux at 77°C. To this solution was added dropwise solution Z1' in which 96.09 bromine was dissolved in 140 ml of carbon tetrachloride! The reaction was carried out for .5 hours. After the reaction, the reaction solution was cooled and titanium tetrachloride 11.79Y
It was added to the reaction solution at 25°C and reacted at this temperature for 3 hours.

Subsequently, bromine 3369'f was added dropwise to the reaction solution at 125°C over 4 hours, and then the temperature was raised to 75°C and heated to reflux for 5 hours.
Time reacted. After washing twice with 450 ml of water, the reaction solution was concentrated to dryness and dissolved in 797,380 ml of water. Add 38% of potassium hydroxide to this solution. Add 7 drops of the solution dissolved in 200 ml of methanol, and heat to reflux under VC2.
Time reacted.

After cooling the reaction solution Z, the precipitated potassium bromide salt w was removed by filtration, methanol was distilled off, and washed with water three times.
BACN 222 g 'a' containing benzene solution 480
m1 was obtained.

As a result of analysis, the obtained Con-BACN had a bromine content of 6
0.54, and the degree of condensation measured by gel permeation chromatography is 244.3 and 201.4.
There were ~8 leaf bodies and 56 chi.

Next, add this Co into the n-hair tongue 21 while stirring.
The n-BACN solution was added dropwise at room temperature for 1 hour. Precipitation of fine powder occurred simultaneously with the dropping. After stirring for 30 minutes after dropping, the powder was separated and dried at a temperature of 75°C to a melting point of 11.
Reddish brown powdered Can-BACN 18 at 8-146°C
5.4 gY was obtained.

Con-HAC from Con-13ACN be/zene solution
The N recovery rate corresponds to 83.5%.

Next is P liquid? By distillation, it was possible to separate and recover benzene and n-hegeta with purity levels of 98 or higher. No problems were observed even when the product was reused for subsequent reactions or reprecipitation.

Comparative Example 1゜0.544 carbon tetrachloride solution containing 94 g of Con-BACN produced in Example 1! Ge, cold acetone (θ~
= 10° C.) 2.21 and entrained. After dropping, the precipitated powder wP was separated and dried, with a melting point of 126-146°C (1) Con-13ACN 65.8, ji, a yellowish brown powder.
'l: Got it.

From Con-BACN carbon tetrachloride solution to Con-BA(
, "N recovery rate corresponds to 70%. In the P solution, Co
Although 28.2 g of n-BACN, carbon tetrachloride, and acetone were contained, the solvent formed an azeotropic mixture, and it was not possible to separate and recover carbon tetrachloride with high purity by distillation.

Patent Applicant: Toyo Soda Kogyo Co., Ltd. Procedural Amendment May 11, 1980 Mr. Kazuo Wakasugi, Commissioner of the Patent Office ε71 1 Indication of Patent Application No. 201920 1988 2 Name of Invention Separation of Brominated Acenaphthylene Condensate Relationship with 111 persons making amendments under the Recovery Act Patent applicant 4th supplement I [Date of order... Voluntary Contents of Kusunoki 7th amendment to "Detailed description of the invention" of the specification subject to 6th amendment (1) Details The document is amended as follows.

Page line Before correction After correction 3　13　10 or less is referred to as 10 or less.

Preferable.

13　2　dimer or less　monomer 13 2 trimer dimer 13 2 4-8mer 3-8mer 15 17 Dimer or less Monomer 1517-18' pentamer dimer 15 18 4-8mer 6-8mer

Claims (1)

[Claims] In a method for separating and recovering a brominated acenaphthylene condensate produced by bromination, condensation and dehydrobromination reaction of acenaphthene, a solution of the obtained brominated acenaphthylene condensate is a saturated aliphatic hydrocarbon having 5 to 9 carbon atoms. A method for separating and recovering a brominated acenaphthylene condensate.