JPS5925355A - Control of amine color development by addition of borohydride - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Various amines are normally produced as colorless liquids, but such products darken to a maximum color when exposed to light and air. . The brown color can thus be largely removed by distillation, but upon subsequent re-exposure the brown color reappears.

The problem of blackheads has been approached in the past by combining low levels of borohydride with freshly distilled amines. Such procedures are rarely useful in stabilizing these dinasties against color degradation during storage, handling, and use. This prior art approach is described in U.S. Pat.
No. 76, No. 1,207,790, No. 3, Mul,.1
/No. 0 and No. 3, Ta 11, No. 306, Tokko Akira! r/
-/'79, J. // issue and 'l q- 9! ,9
θri number and France l d o th/, 47 left de, otsu 3'
J and No. 10/0,727.

The present invention seeks to suppress amine color formation by adding borohydride during the amine manufacturing process, rather than adding such additions to the final product.

As will become clear from the following section in 1-H, some important benefits may be obtained by practicing the present invention.
1 lil1 method, which method includes supplying an amine-forming product containing impurities that lead to discoloration in the amine produced from the reactants, and providing a borohydride-containing compound effective in suppressing discoloration of the amine. and converting the reactants to form the amine. This procedure or procedure produces an amine that is less prone to discoloration than not adding a pyrolyzate-containing compound to the reaction.

The invention will be explained in more detail below.

Different amines including aromatic amines, aliphatic amines, alkanolamines, aliphatic amines, and related amine derivatives have been produced experimentally.

They are each produced by various methods; however, aromatic amines are generally produced by reduction of the corresponding aromatic nitro compounds. This enemy source is usually continuous,
Things like aniline, which is carried out by catalytic, high pressure hydrogenation, but other methods can be used (eg iron and hydrochloric acid), are prepared by this catalytic reduction of nitrobenzene.

Fatty amines (RNH2, Tasoshi I (=C8-C2o aliphatic chain) are likewise prepared in batches or in a continuous process by catalytic hydrogenation of nitrile groups.

Alcasolamines and aliphatic amines are generally prepared by alkylation of ammonia or other amines.

+1-[-thylene also) for alkanolamines:
, J: 7" lopylene oxide is used as the alkoxylation or algylation agent; in the case of aliphatic amines, the corresponding extended alkyl is generally used as alkylation All. The process also applies to various primary amines. (including aromatic amines and monolithic amines) to secondary and tertiary amines.

As can be seen from the above, there is a considerable variety of methods for the production of various amine products. An exhaustive enumeration of such methods is not necessary to further clarify the principles of the invention, as all such methods are common and well known to those skilled in the art.

In order to give more detailed information on the types of common amine production methods (y),
Encyclopedia op Chemical Technology (Otbmer)
fChemical Teology)J
3rd edition, volume / volume, ta<z+ to 760
Page 37A of Volume 1, Volume 1, Volume 1, Volume 1, Volume 1, Volume 3, Volume 1, Volume 1, Volume 1, Volume 1, Volume 1, and Volume 3, page 37A are added hereto as references.

In all of these processes, various processing steps are usually used for the partial L' or purification of the final amine product. These include distillation or water extraction and various other steps.

What happens to all of the above amines is
This is a problem of discoloration or color deterioration. This degradation is generally believed to be the result of oxidation and/or subsequent condensation of oxidized impurities. In addition, the rate of oxidation or subsequent darkening may be affected by ultraviolet light, heat, F6+4°1, co++, Nl
7 What kind of various gold M III! Promoted by ions. All commercially available amines are subject to this degradation because it is not possible to completely exclude oxygen during amine processing, and because both heat and exposure to metals and cations occur during processing. Furthermore, since this degradation is usually due to only trace levels of impurities, conventional purification is often not suitable for removing these impurities.

The present invention uses hydrogenated boronate-containing compounds to reduce these oxidized impurities' or metal cation catalysts for oxidation, making the resulting product highly insensitive to color degradation or darkening. It has been found that these amines can be advantageously used during the processing and manufacturing of these amines.

Unhydrogenated borohydride-containing compounds suitable for use in the practice of this invention include quaternary ammonium borohydride compounds such as: borohydride-4 tetramenal ammonium, natraethylan7ium borohydride, Tetrabutylammonium borohydride, or R-N(CH3)3 borohydride (R-C6H5CH2 or an aliphatic group having t-, 2o carbons) J alkali gold (=ti borohydride) The compounds include #-i sodium borohydride, lithium borohydride and potassium borohydride.

The hydrogenated boba-containing compound can be added in the form of a powder or a suitable solution. Commercially, borohydride (IJ) is available as a powder (97% active) or as an aqueous caustic solution (97% active).

These products or the above-mentioned boron hydride-containing compounds (or solutions or slurries made from these) are combined with specific amines and the Nishizo method or the Remanufacturing method to be used.
It can be changed and used.

Bow hydride is about 100% based on 1tit of reactant.
It has been found that when added to concentrations up to 0 ppm, amine products can prevent horses for commercially significant periods of time, such as 3 to 6 months. Any deviation in excess of 10 θ Oppm in the above would serve no further coloring purpose and would therefore be wasteful. Typically the borohydride is
70 or more based on 1 ml of reactant flow at the time of addition! ;
It is added at a density of about 0.00 ppm.

The borohydride-containing compound can be added at any convenient point during the amine production process prior to production of the final product. The method used for commercial amine production is 1161
Although there are potential addition points for different glazes due to their differences, some addition points are preferred for ease of mixing.

They are: a. If an alkylation or alkoxylation step is involved, the borohydride can be added to the ammonia or amine before the alkylation or alkoxylation. For example, the compound can be added to the ammonia or amine as a precursor. A precursor to AfI can be added to the primary or secondary amine to alkylate or alkoxylate the product following a secondary or tertiary amine; Wash or extract the compounds containing houμ into an aqueous solution
C6 Generally, when distillation is involved, the borohydride-containing compound is added to the column as a feed for the distillation or during the distillation, or into the reflux return product of the column. be able to.

With such a careful selection of addition points,
I4 manufacturers can effectively use alltfA based on borohydride into the final amine product without destroying any of the hydrogenated boro-N-containing compounds or their by-product side groups. can. This is due to the fact that the compounds and such compounds are removed during processing, rather than the final amines that are added to the product. There is a sign C.

The following implementation further illustrates embodiments and advantages of the invention.

EXAMPLE/A freshly distilled aniline that has not been treated with a borohydride-containing compound is tested at regular intervals of 11 JI for the formation of V. During this test, the aniline sample is Exposed to air. The sample was stored at 25°C in a 7)'7 bottle and was 4.3 crn above the sample. 273
It was exposed to ultraviolet light from Watts Ultraviolet Lang for 1.1 days.

The result is shown by the first inner middle curve A.

The P t /Co color evaluation shown in FIG.
This was obtained by using Seigo's "Liquid Color Muku Quasi Test Method (Platinum-Cobalt Scale)" of TM Test Rihachi 209-69. The discoloration was so severe that the use of donor color evaluation was started on day 1. The I-donor color is +1111 determined by ASTM D/LeftlIdr tg r transparent liquid color (Gardner color table), 1,
A line was placed on the graph to line up with the Pt/Co data.

To one sample of the same aniline feed used above was added 2 ml of sodium borohydride prior to distillation,
The same distillation procedure was used.

Curve B in Figure 1 shows the excellent color stability of this material. All storage conditions were the same for both samples.

Example 1 In addition, a concentrated sodium borohydride powder of A4 was used as purified M1ζ of diethylenetriamine (DET) obtained from fractional distillation of a raw material.

The powder was added before the distillation step. As seen in FIG. 2, considerable color stability was obtained with these additives. 1) E 'l' A represents t
Nos. 13. C and D are o and os respectively
Threat, θ, 2. ! % and represents the addition of 0.07% sodium borohydride.

[Brief explanation of drawings]

Figure 1 shows the distilled untreated aniline (curve A) and the aniline treated with sodium borohydride powder before the final distillation.
2 is a plot showing color change over time for IJ (curve B). Figure 1 is a plot of the color formation of diethylenetriamine with addition of glazed sodium borohydride powder before fractionation. Continued from page 10 Inventor Richard A. Mikulski 8 Briggs Street, Salem, Massachusetts, USA 01970 Procedural Amendment Writing Method) 58. g. Kazuo Wakasugi, Commissioner of the Japan Patent Office, Date of Month, Showa, 1983, Case Indication Patent Application No. 93283, 1983
No. 2, Title of the invention Method for suppressing the formation of amine color by addition of borohydride 3, Relationship to the amended case Applicant name Thiokol Corporation 4 Address of agent 3 Marunouchi, Chiyoda-ku, Tokyo Chome 3-1 Telephone (Main) 211-8741

Claims (1)

[Scope of Claims] (1) Supplying a reactant that produces an amine, the reactant containing an impurity that discolors the pre-Hα amine, and hydrogen of f+t effective for suppressing the discoloration of the pre-Hα amine. adding a borohydride-containing compound; converting the reaction mixture to form an amine; A method of inhibiting color formation in amines, including. (2) The method according to Section 1, Section 111, wherein the amine is selected from aromatic amines, alkanolamines, Group 11 aminoaminoamines, and polyamines. (3) '7IJ boron hydride compound is 1Aλ
selected from the group consisting of tetraammonium borohydride and alkali metal borohydride, /l
, F i7'f A method according to item 7. (4) Patent t:11; R(/J) Ijrf where the borohydride above I contains thorium hydride
iIj'NJ3 term jjl: method of lIj'2. (51 before G [; boron hydride-free compound f proboscis is jlfJ
Based on the weight of the reactant, 12) up to 1000 ppm) 11 in 7L, bamboo rrF, i1 ihe's l
(・(Σm = 8 / term T1 - 1χ method. ■Procedure of Section S, Section 11 (((1) If a 1:1 borohydride-containing compound is used during the process and the distillation step is added,
'1'T IF'1' rIW range of determination The method described in item 1 (81i'+lr hydrogenated small hydrogen-containing liquid is AiJ steaming X) Reflux return section of the distillation column used in γ stage 1. (・This
55 added, blasphemy. 〆I Scope of Requirement Method as described in Paragraph 1 -
0(9) 'rift M+' dihydric boron-containing compound is a precursor -'ffC is a secondary amine, 1)
[Patent R added before algylation or alkylation of the first amine to the next secondary or tertiary amine)
9. The method described in item 1 of the scope of claim. 0α The borohydride-containing compound is tetraammonium borohydride, Claim 3F: Self-destructive method. 0υ is, especially l←yf
The method described in the first θ term of the range of t-calculation. (1) The method according to claim 70, wherein the quaternary ammonium borohydride is tetraethylammonium borohydride.・Claim (14) wherein the quaternary ammonium borohydride is /
or more alkynoleno, (b − : Lo
11bI is a tetraalkyl an7nium borosilicate having a carbon atom of -4- or a pennol group,
Patent request ljj) Box/0 item 1 method. (Country Boron hydride
JIF: How to ν to yourself. 116) =+1 Boron hydride-containing compound is added in powder form, in the range of f}・Chi'F 7 {The method of claim No. 1/D, in which a total of 11 hydrides are added in the form of 1 liter of water. Boron compounds are 1) I}amin 1) g:l! In the process of i+・t.・Water-based or other liquids used? /l,
? -The introduction is added to the extraction, l samurai 斤'f Nf
4; I), The method of the first/Koshiki war.