JPH04197407A - Purification of polyethers - Google Patents

Abstract

PURPOSE:To purify high viscosity polyethers by adding an adsorbent composed of magnesium silicate having specific properties to a crude product to apply adsorbing treatment thereto and subsequently filtering the crude product thus treated through a filter precoated with a filtering aid composed of diatomaceous earth having specific properties. CONSTITUTION:High viscosity polyethers with a high MW are prepared using an alkali metal or multicomponent metal cyanide complex catalyst. An adsorbent composed of magnesium silicate having a mean particle size of 100mum or more is added to the obtained crude product to perform the adsorbing treatment of the crude product. Subsequently, the crude product thus treated is filtered through a filter precoated with a filtering aid composed of diatomaceous earth having a mean particle size of 100mum or more. By this method, filtering can efficiently be performed and polyethers are purified.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a purification method for removing a catalyst from high viscosity polyethers containing a catalyst.

[Prior Art] Polyethers obtained by ring-opening reaction of monoepoxides such as alkylene oxides with initiators are widely used as raw materials for synthetic resins such as polyurethane, surfactants, lubricants, and other uses. The initiator is ASH).

It is a hydroxyl group-containing compound represented by (A: a residue obtained by removing the hydrogen atom of the hydroxyl group of the hydroxyl group-containing compound, n: an integer of 1 or more). Examples of initiators include monohydric alcohols, polyhydric alcohols, monohydric phenols, and polyhydric phenols. Compounds having a hydroxyalkylamino group (alkanolamines, amines-alkylene oxide adducts, etc.) are also used as initiators. Furthermore, polyethers obtained by reacting the above initiator with a monoepoxide can also be used as initiators.

Polyethers are the following compounds obtained by subjecting the above initiator to a ring-opening addition reaction of a large number of monoepoxides.

A -E+-R-0+-fflH]- -+R-0+-: Ring-opening reaction unit of monoepoxide m: Integer Usually, as a method for producing polyethers, a method of reacting monoepoxide in the presence of an alkali catalyst is used. Widely used. Alkali metal compounds such as potassium hydroxide and sodium hydroxide have been used as alkali catalysts.

However, polyethers obtained using an alkali catalyst have the following problems. In other words, an unsaturated monool produced by isomerization of a monoepoxide, especially propylene oxide, serves as an initiator, and an unsaturated polyether monool (hereinafter also referred to as an unsaturated monool) is produced by ring-opening addition of a monoepoxide to this. do.

The rate of isomerization increases as the molecular weight of polyethers increases, and this tendency becomes noticeable when the molecular weight is 6,500 or more (in the case of trifunctional), so when propylene oxide is used as the monoepoxide, polyethers with a molecular weight of 6,500 or more It was virtually impossible to synthesize this kind.

On the other hand, it is known that polyethers can be produced using multimetal cyanide complexes as catalysts (US 32
78457. US 327845g, US 32784
59°US 3427256. US 342) 334.
US 3427335). This catalyst produces less of the above-mentioned unsaturated monools and is also capable of producing extremely high molecular weight polyethers.

[Problem to be solved by the invention] When polyethers are produced using an alkali catalyst or a multimetal cyanide complex catalyst as described above, purification is usually required to remove the catalyst from the produced polyethers. It is. For example, when polyethers are used as raw materials for polyurethane resins, the presence of the above-mentioned catalysts tends to cause abnormal side reactions in the polyurethane forming reaction. The removal of alkaline catalysts is usually done by adding a neutralizing agent such as an acid and reacting with the catalyst to precipitate it as an insoluble salt, or by adding an adsorbent and adsorbing the catalyst to it. A purification method is used in which it is separated from polyethers by filtration. Furthermore, when neutralization is performed, excess acid may be treated with an alkali adsorbent and then filtered.

In the case of a multi-metal cyanide complex catalyst, it is known to deactivate the catalyst with a basic substance and then treat it with an adsorbent or ion exchange resin to remove the catalyst components. In addition, if necessary, the multimetal cyanide complex catalyst can be deactivated with an alkali and at the same time converted into an alkali catalyst, reacted with a monoepoxide, especially ethylene oxide, and then treated by the method described above. Are known.

The method for separating neutralized salts and adsorbents from polyethers is as follows:
Filtration method is almost the only method.

However, the higher the viscosity of polyethers, the more difficult it becomes to filter them.The viscosity of polyethers usually increases as their molecular weight increases.Additionally, a small amount of alkylene is added to a polyfunctional and solid initiator such as sugar. Polyether polyols with a high hydroxyl value and a high number of hydroxyl groups (raw material for rigid polyurethane foam) obtained by reacting oxides also have high viscosity. Conventionally, these high viscosity polyethers are filtered under heating. However, in the solvent dilution method, removing the solvent after filtration is complicated.

As mentioned above, when producing particularly high-molecular-weight polyethers, it is often difficult to perform filtration under high temperature. It is necessary to carry out filtration at a temperature below 160°C.

On the other hand, the neutralized salts and adsorbents are often fine particles, making filtration difficult.

In particular, the multi-metal cyanide complex catalyst is oxidized by alkali. When processed, they form complex salts with insoluble hydroxides and are dispersed as ultrafine particles in polyethers, which tends to clog the filter cloth during filtration and significantly impede filtration.

Further, even if a commonly used adsorbent such as synthetic magnesium silicate is used, the amount of adsorbent required is large and the filtration efficiency is significantly reduced. Therefore, it is desired to develop a new filtration method particularly suitable for the filtration of high viscosity polyethers.

[Means for Solving the Problems] The present invention provides the following inventions that have been made to solve the above-mentioned problems.

In a method for removing a catalyst from a catalyst-containing crude product of high viscosity polyethers obtained by ring-opening polymerization of monoepoxide in the presence of a catalyst, the crude product has an average particle size of 100 μm.
Purification of polyethers characterized by performing an adsorption treatment by adding an adsorbent made of magnesium silicate with an average particle size of 100 μm or more, and then filtering with a filter pre-coated with a filter aid made of diatomaceous earth with an average particle size of 100 μm or more. Law.

The present invention has a viscosity of 80 centimeter voice (
It is preferable to apply this method when purifying polyethers with a temperature of 1.5 cps or higher. In particular, it is applied when the viscosity at 100°C is 100 cps or more and the filtration is performed at a temperature of 100°C or higher. Furthermore, filtration is performed at a temperature of 100°C or higher, and the viscosity at that temperature is 100°C.
It is preferable to apply this method when purifying polyethers of cps or higher. The viscosity of such polyethers at room temperature is usually 2000 cps or more, especially 30 cps or more.
00 cps or more. According to the method of the present invention, filtration is possible even if the viscosity at the filtration temperature is 1000 cps.

In the present invention, it is preferable to deactivate the catalyst before treating the crude product with an adsorbent. For example, when a double metal cyanide complex catalyst is used, an alkali such as sodium hydroxide is added to the crude product to decompose and deactivate the double metal cyanide complex. Water can also be added in the case of an alkaline catalyst. In the case of an alkaline catalyst, it is preferable to neutralize the catalyst in the crude product with an acid in advance to precipitate a neutralized salt.As the acid, inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, carboxylic acids, etc. These include organic acids, acidic salts of these acids, carbon dioxide gas, etc. When a double metal cyanide complex catalyst is used as described above, an alkali such as potassium hydroxide is added to deactivate the catalyst and at the same time deactivate the catalyst. It is also possible to pre-treat the double metal cyanide complex component that has been converted into an alkali catalyst, further reacted with ethylene oxide, etc., and then deactivated the alkali catalyst component by such a method.

In adsorption treatment using an adsorbent, the adsorbent is added to
It is preferable to stir at 50° C. for 0.5 to 3.0 hours, and then dehydrate at 10 to 50 Torr for 0.5 to 3.0 hours to remove moisture. The amount of the adsorbent added varies depending on the amount of the catalyst, its neutralized product, unreacted acid, etc., but is usually 1 to 10% by weight based on the polyether.

In the present invention, the average particle size of the adsorbent is 100 μm.
Use the above magnesium silicate. However, if the particle size is too large, the adsorption efficiency will decrease, so the upper limit is 50.
Approximately 0 μm is preferable. In particular, the average particle size is 150 to 300.
μm magnesium silicate is preferred. Synthetic magnesium silicate is usually used, but natural magnesium silicate may also be used.

The filter aid in the present invention has an average particle size of 100 μm.
Diameters of m or more are used. The particle size of this diatomaceous earth is preferably about the same or smaller than the particle size of the magnesium silicate used. In particular, the average particle size is 100-2
00 μm diatomaceous material is preferred.

Commercially available magnesium silicate and diatomaceous earth having an average particle size of 100 μm or more can be used. For example, product name “Kw-5003N”
, “Kw-63DSN” (Kyowa Chemical Industry (
Co., Ltd.), “AD60ONS”, “AD600G”, “
Synthetic magnesium silicate such as "A050ONS" (manufactured by Tomita Pharmaceutical Co., Ltd.), product name "Radiolite #30"
Diatomaceous earth such as 00'' (manufactured by Showa Kagaku Kogyo Co., Ltd.) can be used.

A filter pre-coated with a filter aid is usually prepared by dispersing the filter aid in a liquid carrier, passing this through the filter, and coating it on the filter. The liquid carrier is not particularly limited, but may be polyethers in the present invention. Polyethers may be used after adsorption treatment with addition of magnesium silicate. It is preferable that the polyethers used in this precoat treatment be recovered and purified by applying the method of the present invention.

Filtration can be performed using various filters. As the filter, for example, a filter paper, a wire mesh filter, a cloth filter, etc. can be used. Usually, a pressure filter is used to perform filtration under heat and pressure.

The polyethers in the present invention are compounds obtained by reacting a large number of monoepoxides with an initiator in the presence of a catalyst as described above. Particularly preferred is polyoxyalkylene polyol. A polyoxyalkylene polyol is obtained by sequentially subjecting an initiator having at least two hydroxyl groups to a monoepoxide such as alkylene oxide through a ring-opening addition reaction.

Polyethers have a molecular weight of about 5,000 or more, especially about 8
It has a high viscosity of 000 or more. In particular, the molecular weight obtained using a double metal cyanide complex catalyst is 8000 to 5oo
oo polyoxyalkylene polyol.

As the initiator, polyhydroxy compounds having 2 to 8 hydroxyl groups are particularly preferred.

Examples of polyhydroxy compounds include dihydric alcohols such as ethylene glycol and propylene glycol;
Trihydric alcohols such as glycerin, trimethylolpropane, and hexanetriol; tetravalent or higher alcohols such as pentaerythritol, diglycerin, dextrose, sorbitol, and sucrose; and alcohols obtained by reacting these alcohols with monoepoxides such as alkylene oxide. There are polyethers with a lower molecular weight than the target product. In addition, bisphenol A, resol,
Compounds with phenolic hydroxyl groups and methylol groups such as novolak, compounds with hydroxyl groups and other active hydrogens such as ethanolamine and jetanolamine, and target products obtained by reacting these with monoepoxides such as alkylene oxides. There are low molecular weight polyethers.

Furthermore, there are polyethers having a lower molecular weight than the target product obtained by reacting a monoamine or polyamine having at least two hydrogen atoms bonded to a nitrogen atom with a monoepoxide such as alkylene oxide. In addition, phosphoric acid, its derivatives, and other polyhydroxy compounds can also be used. Two or more types of these polyhydroxy compounds can also be used in combination.

The present invention can also be applied to a method for manufacturing polyether monool by causing a monovalent initiator to undergo a ring-opening reaction with a monoepoxide. As monovalent initiators, for example, methanol, ethanol, butanol, hexanol, other monools, phenol, phenol derivatives such as alkyl-substituted phenols, and the target products obtained by reacting these with monoepoxides such as alkylene oxides. There are low molecular weight polyethers. Furthermore, there are polyethers having a lower molecular weight than the target product obtained by reacting a monoamine or polyamine having one hydrogen atom bonded to a nitrogen atom with a monoepoxide such as alkylene oxide.

The monoepoxide in the present invention is a monoepoxide having 2 or more carbon atoms, and particularly preferably an alkylene oxide having 2 or more carbon atoms. More preferably, alkylene oxides having 2 to 4 carbon atoms such as propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, epichlorohydrin, and ethylene oxide are preferred, and propylene oxide is most preferred.

They can be used alone, two or more of them, or in combination with other monoepoxides such as styrene oxide, glycidyl ether, and glycidyl ester. In the case of using two or more alkylene oxides or alkylene oxide and other monoepoxides, they can be added as a mixture or added sequentially to form a random polymer chain or a block polymer chain.

The double metal cyanide complex catalyst in the present invention is considered to have the structure of the following general formula (1) as shown in the above-mentioned known examples.

M-[M'x(CN)ylb(HzO)c(R)a
・(1) However, M is Zn(II), Fe(II
), Fe(III), Co(II), N1(II),
Al(III), 5r(II), Mn(II), Cr(
II, Cu('II), 5n(II), Pb(U), M
o(■), Mo(Vr), W(TV), etc. W('
i'I), and M' is Fe(II), Fe(III)
, Co(II), Co(m), Cr(II), Cr(I
[[), Mn(IN, Mn(III), N1(II),
V (IV), V (V), etc., R is an organic ligand, and a.

b, x and y are positive integers that vary depending on the valence and coordination number of the metal, and C and d are positive numbers that vary depending on the coordination number of the metal.

M in general formula (1) is preferably Zn(II) M'
are Fe(II), Fe(III), Co(II), Co
(I[I) and the like are preferred. Examples of organic ligands include ketones, ethers, aldehydes, esters, alcohols, amides, nitriles, and sulfides. Preferred are ethers, esters, alcohols, amides, etc., specifically, for example, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, t
-butanol, N,N-dimethylacetamide, etc.

The polyether polyol obtained by the present invention is most useful as a polyol for polyurethane raw materials used alone or in combination with other polyols. Furthermore, the polyether poly(or mono)ol obtained by the present invention can also be used as a raw material or additive for synthetic resins other than polyurethane. Furthermore, it can be used as a lubricating oil, an insulating oil, a hydraulic oil, and other oils, or as a raw material thereof.

Furthermore, the polyethers obtained according to the present invention can be converted into other compounds such as alkyl ether compounds and acylated compounds and used for various purposes.

EXAMPLES The present invention will be specifically explained below using Examples and Comparative Examples, but the present invention is not limited only to these Examples.

[Example] A polyoxypropylene polyol was synthesized using a catalyst, and the crude product was pretreated. Obtained polyol A-C
is shown below. Examples and comparative examples described later were carried out using this polyol.

Polyol A synthesized using dizinc hexacyanocopartate complex as a catalyst, molecular weight 10,000.25°C, viscosity 3
000 cps of polyoxypropylene triol.
A catalyst decomposition product (Zn 50ppm,
A crude polyoxypropylene triol containing 27 ppm Co) and 0.2 wt% NaOH.

Polyol B: Molecular weight 19,000.25°C, viscosity 25,000c synthesized using zinc hexacyanoiron complex as a catalyst
Catalyst decomposition product (Zn 70 ppm, Fe 40 ppm) obtained by adding 0.2 wt% of sodium hydroxide to PS polyoxypropylene diol to deactivate the catalyst.
m) and a crude polyoxypropylene diol containing 0.2 wt% of NaOH.

Polyol C: Molecular weight 640.25°C, viscosity 31000 cps, residual NaOH obtained by reacting propylene oxide with sucrose using sodium hydroxide as a catalyst.
O, 2 wt% unrefined polyol.

Example 1 Synthetic magnesium silicate with an average particle size of 240 μm (trade name “Kw-500SN”, manufactured by Kyowa Chemical Industry Co., Ltd.) in polyol A
Co., Ltd.) in an amount of 4% by weight, heated and stirred at 120° C. for 3 hours, and then degassed under reduced pressure at the same temperature of 20 Torr for 2 hours. Polyol subjected to the above treatment using a pressure filter using No. 5C filter paper pre-coated with diatom ± (trade name "Radiolite $3000", manufactured by Showa Kagaku Kogyo Co., Ltd.) with an average particle size of 120 μm to a thickness of 5 mm. A was filtered at 100°C (the viscosity of polyol A at 100°C was 200 cps).

As a result, the purified polyol A obtained was transparent, the filtration rate was 700 kg/m"・Hr, the yield was 99%, and the C
PR is 3.5, residual Zn is 5ppm, residual Co is 2p9
(2) Residual Na was 3 ppm.

Comparative Example 1 Synthetic magnesium silicate (trade name "Kw-60O3", Kyowa Chemical Industry Co., Ltd.) with an average particle size of 55 μm or less was added to polyol A.
Co., Ltd.) in an amount of 4% by weight, and adsorption treatment was carried out under the same conditions as in Example 1. Thereafter, filtration was carried out under the same conditions as in Example 1 except that diatomaceous material ± (trade name "Radiolite #600", manufactured by Showa Kagaku Kogyo Co., Ltd.) having an average particle size of 14 μm was used.

As a result, the purified polyol A obtained was transparent, the filtration rate was 120 kg/m"Hr, the yield was 70%, and the CP
R is 3.3, residual Zn is 15ppm, residual CO is 8p
The pI was 11, and the residual Na was 5 ppm.

Example 2 Synthetic magnesium silicate with an average particle size of 240 μm (trade name “Kw-500SN”, manufactured by Kyowa Kagaku Kogyo Co., Ltd.) was added to polyol B.
Co., Ltd.) in an amount of 4% by weight, heated and stirred at 120° C. for 4 hours, and then degassed under reduced pressure at the same temperature of 15 torr for 2 hours. Polyol subjected to the above treatment using a pressure filter using No. 5C filter paper pre-coated with diatom ± (trade name "Radiolite 13000", manufactured by Showa Kagaku Kogyo Co., Ltd.) with an average particle size of 120 μm to a thickness of 4 mm. A at 125℃
(The viscosity of polyol B at 125° C. was 1000 cps).

As a result, the purified polyol B obtained was transparent, the filtration rate was 210 kg/m''-Hr, the yield was 95%, and the C
PR is 5. l, residual Zn is 6 ppm, residual Fe is 3 ppm
m, and residual Na was 7 ppm.

Comparative Example 2 Synthetic magnesium silicate (trade name "Kw-1000", Kyowa Chemical Industry Co., Ltd.) with an average particle size of 65 μm or less was added to polyol B.
Co., Ltd.) in an amount of 4% by weight, and adsorption treatment was carried out under the same conditions as in Example 2. Thereafter, filtration was carried out under the same conditions as in Example 1 except that diatomaceous earth (trade name "TOBUCO #31", manufactured by Showa Kagaku Kogyo Co., Ltd.) having an average particle size of 11 μm was used.

As a result, the purified polyol A obtained was transparent, the filtration rate was 30 kg/m"・Hr, the yield was 20%, and the CP
R is 5.3, residual Zn is 201) E) li+, residual F
e was 11ppm, and residual Na was 20ppo+.

Example 3 Synthetic magnesium silicate with an average particle size of 180 μm (trade name “Kw-630SN”, manufactured by Kyowa Kagaku Kogyo Co., Ltd.) was added to polyol C.
Co., Ltd.) in an amount of 2% by weight, heated and stirred at 120° C. for 2 hours, and then degassed under reduced pressure at the same temperature of 30 torr for 2 hours. Diatomaceous earth (trade name: "Radiolite 13000", manufactured by Showa Kagaku Kogyo Co., Ltd.) with an average particle size of 120 μm was deposited to a thickness of 5 µm.
Polyol C, which had undergone the above treatment, was filtered at 90°C using a previous year type filter using No. 5C filter paper pre-coated with m+o (the viscosity of polyol C at 90°C was 1
50 cps).

As a result, the obtained purified polyol A was transparent, the filtration rate was 1100 kg/m2・Hr, the yield was 99%, and the C
PR was 12.

Comparative Example 3 Synthetic magnesium silicate (trade name "Kw-600S", Kyowa Chemical Industry Co., Ltd.) with an average particle size of 55 μm or less was added to polyol C.
Co., Ltd.) in an amount of 2% by weight, and adsorption treatment was carried out in the same manner as in Example 1. Thereafter, filtration was carried out under the same conditions as in Example 3 except that diatomaceous material ± (trade name "Radiolite #600", manufactured by Showa Kagaku Kogyo Co., Ltd.) having an average particle size of 14 μm was used.

As a result, the purified polyol C obtained was transparent, the filtration rate was 500 g/m"・Hr, and the yield was 80 mice.
CPR was 13.

[Effects of the Invention] According to the present invention, when high viscosity polyethers produced using an alkali catalyst or a multimetal cyanide complex catalyst are purified by filtration, filtration can be performed efficiently. In particular, it is capable of sufficiently and efficiently removing the catalyst components of very high molecular weight polyethers (which have very high viscosities) produced using multi-metal cyanide complex catalysts.

Claims (1)

[Claims] 1. A method for removing a catalyst from a crude product containing a catalyst of high viscosity polyethers obtained by ring-opening polymerization of a monoepoxide in the presence of a catalyst, wherein the crude product has an average particle size of 10
Purification of polyethers, characterized by performing adsorption treatment by adding an adsorbent made of magnesium silicate with an average particle size of 0 μm or more, and then filtering with a filter pre-coated with a filter aid made of diatomaceous earth with an average particle size of 100 μm or more. Law. 2. The purification method according to claim 1, wherein the catalyst is a multi-metal cyanide complex catalyst, and after deactivating the catalyst, an adsorbent is added and filtration is performed.