JPH05345821A - Decoloration of polyalkylene polyamine - Google Patents

Abstract

PURPOSE:To obtain a polyamine product having extremely faint color and high quality under mild condition by hydrogenating a polyalkylene polyamine in the presence of a palladium catalyst supported on alumina or titania. CONSTITUTION:A polyalkylene polyamine is decolored by heating in hydrogen atmosphere preferably at 50-180 deg.C and hydrogen partial pressure of 5-30kg/cm<2> in contact with a palladium catalyst supported on alumina and/or titania. The use of a fixed-bed continuous reactor is preferable for industrial purpose. The catalyst is generally produced by using palladium chloride, palladium nitrate, etc., as a raw material, supporting palladium on a carrier by impregnation method, drying the product and reducing in hydrogen gas flow under heating or reducing with a reducing agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for decolorizing polyamine products. The polyamine product is an industrially useful compound used as a paper-strengthening agent, an epoxy curing agent, a lubricating oil additive, a surfactant and the like.

[0002]

2. Description of the Related Art Generally, polyamine products such as diethylenetriamine (hereinafter abbreviated as DETA), triethylenetetramine (hereinafter abbreviated as TETA), tetraethylenepentamine (hereinafter abbreviated as TEPA) and pentaethylenehexamine (hereinafter abbreviated as TEPA). , PEHA) is industrially produced by the reaction of ethylene dichloride (hereinafter abbreviated as EDC) with ammonia and / or ethyleneamine, or the reaction of ethanolamine with ammonia and / or ethyleneamine.

These ethyleneamines obtained directly from these reaction steps, especially polyethylenepolyamines, have a yellowish brown to dark brown color, and it is a quality problem to make them a product only by a normal distillation separation operation. There is. Therefore, many decolorizing methods for these polyamines have been proposed so far.

For example, polyamine is added in the presence of hydrochloric acid to 200
Examples thereof include a method of heat treatment at ˜230 ° C., a method of treating polyamine with potassium hydroxide, and a method of treating polyamine with ethyleneamine hydrochloride or EDC.

These methods require further neutralization after the decolorization treatment, and then an additional step of separating the salt newly generated by the treatment operation is added. In addition, the problem of corrosion of the equipment material due to salt also occurs.

[0006] On the other hand, a method of adding one of metals such as zinc, tin, and aluminum, and sodium hydroxide or potassium hydroxide to polyamine and heat-treating, and a method of contacting polyamine with zinc and water at room temperature to 150 ° C. There is also a method in which zinc is added to polyamine, followed by heat treatment, a method in which polyamine is treated with heated activated carbon, a method in which polyamine is treated with a sulfonic acid ion exchange resin, or a method in which polyamine is treated with acidic zeolite.

[0007] These methods require a post-treatment step associated with the addition of a metal or other solid, which makes the process very complicated, and also requires the addition of a further post-treatment operation associated with metal elution and deterioration of the resin. However, it has various drawbacks in terms of industrialization.

Further, all of these bleaching methods have been improved to improve various bleaching effects, but the bleaching effect is not sufficient in general, and both the target effect and the industrial operation side are effective. There is a problem in practicality.

On the other hand, Japanese Patent Application Laid-Open No. 48-52,708 discloses a hydrotreating method using nickel, cobalt, chromium and the like, and Japanese Patent Application Laid-Open No. 63-101421 discloses a palladium or carbon using carbon as a support. A decolorization method by hydrotreatment with a ruthenium catalyst is disclosed.

In the case of the hydrotreating method using nickel, cobalt, chromium, etc., there are problems that the reaction is carried out at high temperature and high pressure, the decolorizing effect is not sufficient, and the supported metal is eluted into the amine. In the case of hydrotreatment decolorization using a palladium or ruthenium catalyst, the decolorizing effect is relatively large compared to catalysts such as nickel, cobalt, and chromium, and it can be said that this is a relatively useful method.

[0011]

The polyamine product obtained by the reaction of EDC with ammonia and / or ethyleneamine, or the polyamine product obtained by the reaction of ethanolamine with ammonia and / or ethyleneamine, Polyamine products obtained by known production methods, such as TETA or TEPA, are also tan or brown colored and require some bleaching treatment to obtain a more useful quality product.

However, among the various treatment methods proposed so far, the decolorizing effect capable of producing a high-quality polyamine product having an extremely small degree of coloring is extremely large, and a new by-product accompanying the decolorizing treatment operation is produced. There are few methods that are industrially useful, with no simple production, and a simple process.

That is, it is desired to develop a decolorizing method capable of effectively decolorizing a polyamine product in a pollution-free and simple process to obtain a high-quality polyamine product.

[0014]

DISCLOSURE OF THE INVENTION The inventors of the present invention have made earnest studies on a decolorization method of a polyamine product, and as a result, hydrogenated the polyamine product using a palladium catalyst having alumina and / or titania as a support. It was found that a high-quality polyamine product with extremely little coloring can be obtained by the treatment, and the present invention has been completed.

That is, the present invention provides a method for decolorizing a polyamine product, which comprises subjecting the polyamine product to heat contact with a palladium catalyst having alumina and / or titania as a support under a hydrogen atmosphere. It is a thing.

The present invention will be described in more detail below.

The polyamine product to be subjected to hydrogenation of the present invention is generally a reaction product of EDC with ammonia and / or ethyleneamine, a reaction product of ethanolamine with ammonia and / or ethyleneamine. , Formalin, reaction products of hydrocyanic acid with ammonia and / or ethyleneamine, such as DETA, TETA, TEP
Examples include A, PEHA, and higher molecular weight polyethylene polyamines such as hexaethyleneheptamine.

Furthermore, the production method as described above is not particularly limited, and ethylene glycol and ammonia and / or
Or a reaction product of ethyleneamines, a reaction product of propylene glycol and ammonia and / or propyleneamines, a reaction product of aminopropanol and ammonia and / or propyleneamines, propylene dichloride and ammonia and / or propylene Polyalkylene polyamines such as reaction products with amines can also be widely used in the decolorization treatment method of the present invention.

The polyalkylene polyamine is a mixture of various polyethylene polyamines obtained by the above reaction, and ethylene diamine (ED
A) or TETA, TEPA, PEHA, H obtained by distilling off relatively low boiling amines from EDA to DETA
It may be a polyethylene polyamine mixture such as EPA. Alternatively, unbleached distilled TETA, TEPA, PE
Any fraction such as HA or the like, or a mixture thereof can be used in the present invention.

At this time, the impurity species are water, or sodium chloride produced in the neutralization treatment step in the production method using an organic halogen compound as a raw material, or the catalyst used in the production method using monoethanolamine as a raw material. Even if various inorganic compounds such as silica / alumina, titania, and phosphorus compounds, and various metallic impurities such as iron / nickel / chromium contained in the material of the pipes coexist in the polyamine product, In this method, the decolorizing effect is not reduced, and a polyamine product in which these various impurities coexist may be used.

The palladium catalyst of the present invention is palladium /
Alumina catalysts, palladium / titania catalysts and palladium / alumina / titania catalysts, which are supported on these limited carriers. These catalysts
It is excellent in terms of catalytic activity, resistance to amine solution and cost, and can be effectively applied to a wide range for decolorization of polyamine products containing various coloring-causing substances due to production history.

As a method for preparing the catalyst used in the present invention, a catalyst produced by any preparation method such as an impregnation method, a precipitation method, and an evaporation-drying method can be used. In general, a catalyst is used in which palladium chloride or palladium nitrate is used as a raw material, palladium is loaded on a carrier by an impregnation method, dried, and then subjected to heat reduction treatment in a hydrogen stream or reduction treatment with a reducing agent or the like.

The catalyst may have any shape such as powder, granules, pellets, tablets, etc., and can be used in the present invention. Regarding the molding method, the catalyst may be molded by any molding method such as tablet molding, extrusion molding, and pulverization. Further, when a catalyst is prepared by supporting a catalyst metal on a molded carrier by an impregnation method, molding is not particularly required.

The loading amount of palladium metal on the alumina and / or titania support is not particularly limited, but if it is too small, a large amount of catalyst is required to obtain a sufficient effect, and if the loading amount is too large. However, no significant improvement in decolorization effect was observed despite the cost increase. Therefore, it is preferably in the range of 0.05 to 10% by weight.

The amount of the catalyst used in the reaction varies depending on the degree of coloring, the reaction conditions, etc., but in the batch reaction, it is 0.0% as palladium metal based on the polyamine product.
It may be in the range of 01 to 1% by weight, preferably 0.0.
It is 05 to 0.1% by weight. If it is less than 0.001% by weight, the decolorizing effect is small, and if it is added in an amount of more than 1% by weight, a remarkable improvement in the effect may not be observed.

The reaction temperature is usually in the range of 30 to 200 ° C, preferably 50 to 180 ° C. If the temperature is lower than 30 ° C, the reaction rate is slow, which is industrially disadvantageous. If the temperature is higher than 200 ° C, the decomposition reaction occurs simultaneously.
It may cause deterioration of product quality.

The hydrogen partial pressure during the reaction is carried out in the range of 1 kg / cm ² or more, preferably 5 to 30 kg / cm.
It is ² . If the hydrogen partial pressure is too low, the decolorizing effect is reduced, and the decomposition reaction also occurs, which lowers the product quality. On the other hand, even if the hydrogen partial pressure is increased more than necessary, the decolorizing effect is not significantly improved, and the equipment cost is increased.

The reaction may be performed in a batch system, a semi-batch system, or a continuous system. As the reaction device, even in a fixed bed type, a rotating disk type, or the like in which catalyst particles are fixed, stirring tank type, bubble column type, three-phase fluidized bed type catalyst particles are dispersed or suspended in the liquid. A turbid reactor may be used. Among them, the fixed bed continuous reactor is considered to be particularly industrially advantageous.

In the case of a batch system, the reaction time is 0.1 to 10
It is carried out for a time range, but is preferably carried out for 0.5 to 5 hours. In the case of a fixed bed continuous device, the space velocity (LH
SV) is carried out in the range of 0.01 to 10 h ⁻¹ ,
It is preferably carried out for 0.1 to 5 h ^-1 .

When the distillation treatment is carried out after the decolorization treatment of the present invention, the coloring-causing substance which has not been reduced and removed is concentrated and removed in the distillation pot residue, and the product coloring degree can be reduced more effectively. .. However, even if the polyamine mixed product is separated by distillation into each fraction such as DETA, TETA, TEPA, and PEHA, only the fraction requiring decolorization is subjected to the decolorization treatment of the present invention without any problem.

[0031]

The polyamine product treated by the method of the present invention has a very low degree of coloring and is of very high quality. Further, the method of the present invention can be carried out in any of batch-type and continuous-type reaction modes, and since the activity of the catalyst is high, the reaction can be carried out under extremely mild conditions. Therefore, high temperature and high pressure manufacturing equipment is not required.

Therefore, the method of the present invention is a very useful method for decolorizing a polyamine product.

[0033]

EXAMPLES The present invention will be further described below based on examples, but the present invention is not limited thereto.

(Preparation of catalyst) In an aqueous solution of palladium chloride,
A predetermined amount of carrier (alumina or titania) was added, and palladium was sufficiently impregnated, filtered, dried at 110 ° C., and subjected to heat reduction treatment in a hydrogen stream to obtain palladium catalysts shown in Tables 1 to 5.

Examples 1 to 10 In a 500 cc SUS316 autoclave, TETA was added.
Alternatively, 200 g of TEPA was filled. TETA and TEPA used in this example are crude undecolorized TET obtained by distilling and separating the polyamine product obtained by the EDC method.
A, crude TEPA.

A predetermined amount of the hydrogenation catalyst shown in Table 1 was added to the autoclave. After sufficiently replacing the gas phase portion of the autoclave with hydrogen, the autoclave was pressurized to a predetermined pressure, heated while stirring, and reacted at a predetermined temperature for a predetermined time. (Refer to Table 1 for reaction pressure, temperature, and time.) After a predetermined time has passed, cooling is performed,
The catalyst was separated by filtration. Table 1 shows the results of evaluation and comparison of the hues of the reaction solutions thus obtained.

Further, in order to see the effect of the distillation treatment after the reaction, the reaction liquid was distilled under reduced pressure in a nitrogen atmosphere, and the hue of the liquid 98% distilled and recovered was evaluated and compared. Shown in. As a hue evaluation method, ASTM D
The Gardner notation by Gardner colorimeter measurement according to 1544 and the APHA notation using Pt-Co hue standard according to ASTM D1209-62 were used. The Gardner chromaticity is 0 → 0 + → 1- → 1 → 1
As the color changes from + to 2-, the yellow-brown color becomes darker.

The change in the liquid composition due to the reaction was examined by gas chromatography, but no change in the composition due to decomposition or the like was observed in the reaction according to the present invention.

[0039]

[Table 1] Comparative Examples 1-5 Using the same reactor and raw material polyamine as in Examples 1-10, Raney Ni, Ni / diatomaceous earth, 5% as a catalyst
Decolorization was performed using Pd / carbon and 5% Ru / carbon, and the reaction liquid hue after filtering the catalyst and the reaction liquid was 98%.
Table 2 shows the results of evaluation of the hue of the recovered liquid after the recovery by distillation.

When Raney Ni or Ni / diatomaceous earth was used as a catalyst, a decomposition reaction occurred as shown in Table 3, and the composition of the reaction solution was changed.

[0041]

[Table 2]

[0042]

[Table 3] Examples 11 to 15 In Examples 11 to 13, the same reaction apparatus and operation as in Examples 1 to 10 were used, and the crude polyamine product having the composition shown in Table 4 was used as a feedstock and Pd / alumina or Pd / titania as a catalyst. The crude polyamine product was decolorized. The crude polyamine product as referred to herein means TETA obtained from the reaction product obtained by the reaction of ammonia and ethylene dichloride.
It is a mixed polyamine product obtained by removing lower boiling ethyleneamines by a distillation operation.

In Examples 14 and 15, EDA obtained by the ethanolamine method and monoethanolamine were reacted in the presence of a niobium / alumina catalyst to obtain a polyamine product, which had a boiling point lower than that of the reaction product. EDA, DETA,
A mixed polyamine product obtained by removing monoethanolamine by distillation is used as a raw material. Table 5 shows the reaction conditions, the raw materials and the hue of the reaction liquid after the catalyst was filtered. Further, by distilling the reaction solution of Example 12,
When the hue of each of the TETA and TEPA fractions was separated and then measured, the hue of the TETA fraction was 1 in APHA display.
0, the hue of the TEPA fraction was 0+ on the Gardner display, and it was very little colored.

[0044]

[Table 4]

[0045]

[Table 5]

Claims (2)

[Claims] 1. A method for decolorizing a polyalkylene polyamine, which comprises subjecting the polyalkylene polyamine to heat contact treatment with a palladium catalyst having alumina and / or titania as a support in a hydrogen atmosphere. 2. The method for decolorizing a polyalkylene polyamine according to claim 1, wherein the polyalkylene polyamine is diethylene triamine, triethylene tetramine, tetraethylene pentamine and pentaethylene hexamine.