DE1058027B - Process for the preparation of anhydrous ammonium metaborate diperhydrate - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

PATENT LETTER 1 058

REGISTRATION DAY:

NOTICE
THE REGISTRATION
AND ISSUE OF
EDITORIAL:

ISSUE OF
PATENT LETTER:

DBP 1058027 KL.12i 16

INTERNAT. KL. COl b

FEBRUARY 22, 1958

MAY 27, 1959 OCTOBER 12, 1961

AGREES WITH AUSLEG ESCHRI FT 1 058 027 (H 32469 IVa / 12 i)

An ammonium perborate hemihydrate of the formula NH ₄ BO _{3 -VaH 2} O is known from the literature, which rearranges itself into an ammonium metaborate perhydrate of the formula 2NH ₄ B ₂ O _{2 on storage.} These compounds are not very stable and have a relatively low active oxygen content.

It has now been found that a previously unknown anhydrous ammonium metaborate diperhydrate of the formula NH ₄ BO ₂ · 2H ₂ O ₂ is obtained if the procedure according to the invention described below is used. This consists in reacting boric acid, at least 30% hydrogen peroxide (all information relating to this is based on percent by weight) and ammonia in a molar ratio of 1: (2 to 6): (1.05 to 3), with Ammonia is added in the form of an aqueous, preferably concentrated solution after mixing the other two components.

When carrying out the process, it is expedient to work at low temperatures, ie between 0 and 30.degree. C., preferably between 10.degree. And 25.degree. This ensures that the reaction is carried out with practically no loss of hydrogen peroxide, especially since the mother liquor can be used again for a new batch after the crystals have been separated off. It is also advantageous to use a molar ratio H ₃ BO ₃ : H ₂ O ₂ such as 1: (3 to 5), ie to work with a considerable H ₂ O ₂ excess. Finally, it is advisable to use concentrated aqueous ammonia solutions, including those with an optimal saturation limit at 0 ° C.

Using e.g. B. 40% H ₂ O ₂ dissolve at temperatures up to 25 ° C only about 5 parts of the boric acid expediently added in powdered form in 100 parts of H ₂ O ₂ , so that the main part is present in undissolved form as sediment. If such a suspension is mixed with concentrated ammonia with vigorous stirring up to the equivalence point, ie only as much ammonia solution is added as the ratio NH ₃ : H ₃ BO ₃ as 1; 1 corresponds, all boric acid dissolves, so that a perfectly clear solution is obtained. With further addition of ammonia, the diperhydrate separates out in a well-crystallized form and with an almost quantitative yield. Recrystallization of the product is generally not necessary. Any moisture residues adhering can be removed by drying in vacuo at 30 to 50 ° C. The mother liquor obtained after the crystals have been separated off can, as already explained above, be used for a new batch.

The metaborate process for production that can be produced in this way, free of water of crystallization

of crystal water-free

Ammonium metaborate diperhydrate

Patented for:

Henkel & Cie. G.m.b.H., Düsseldorf-Holthausen

Dr. Valentin Habernickel, B'ergheim / Sieg,

and Dr. Friedrich Weldes, Düsseldorf-Benrath,

have been named as inventors

Diperhydrate is colorless, storable and stable up to about 120 ° C. It has a relatively high content of hydrogen peroxide, about 53 per cent. The _pH value of l ° / o solution at 20 ° C is ^about%. 9

The new compound is excellent for making bleach baths and can be used for Detergents, cleaning agents and dispersants, if necessary in combination with other known substances, such as, in particular, alkalis, detergent substances, phosphates, silicates and the like, are used.

example

A mixture of 600 parts of boric acid and 2000 parts of 40% H ₂ O ₂ is slowly mixed with 450 parts of ammonia in the form of a 25% solution with vigorous stirring so that the temperature does not exceed 20 ° C. The now clear The solution is cooled to 5 to 10 ° C. and a further 100 parts of ammonia solution of the above concentration are added.

After determining the remaining H ₂ O ₂ and ammonia content and adjusting to the initial concentration, the mother liquor is used again for a new batch. The mother liquor is expediently regenerated with 60 to 70% H ₂ O ₂ .

The ammonium metaborate diperhydrate obtained in this way is used as a bleaching agent in a mixture with conventional wetting agents as well as with inorganic substances known for cleaning purposes, especially for heavy duty detergents, suitable.

109 693/289

Claims (1)

3 4 A particularly good coarse detergent has to do with the detergent composition. Here-r for example as follows: through can valuable others if desired Fatty alcohol sulfate 15 ° / detergent substances used in increased quantities Alkylbenzenesulfonate ''. \ ^ '.'. '.'. '.'. '.'. \ '.'. 10 · / «Γΐ ^ ^The * ^rti s ^e detergents are preferred Water glass (SiO ₂ : Na ₂ O = I: 3.5) .. 2% ⁵ * ^u ™ \ Spray drying in spherical form obtained It Magnesium sulfate 3 Vc f l ^edoc * appropriate, the ammonium perborate dem Fettsäureäthanolamid 2% ^Fertl S add ^en Spruhprodukt. Sodium chloride. 3% patent claims: Tripolyphosphate 15%. Pyrophosphate 10% ¹⁰ Process for the production of knallwasser- Sodium sulfate 25% free ammonium metaborate diperhydrate of the Ammonium metaborate diperhydrate '. "'. '. 3% composition NH ₄ BO ₂ · 2 H ₂ O ₂ , thereby Optical brightener 0.1% ^ '«refuses to use boric acid, at least The remainder of the water is iges water peroxide and ammonia in the 15 molar ratio 1: (2 to 6): (1.05 to 3) to convert This detergent can, if desired, cause ammonia to settle, in the form of a Coloring of the overall composition with a dye, aqueous, preferably concentrated, solution be set. The product is in a concentrate after mixing the other two components tration of 6 to 8 g / l used. Is added by the high. H ₂ O ₂ content (about 53%) it is possible for the 20 2. The method according to claim 1, thereby targeting the required bleaching effect, in contrast, indicates that the reaction with 40 to sentence to a use of normal Sodium 70% H ₂ O ₂ at temperatures between 0 and perborate, with an amount of only 3 ⁰ Io, based on 30 ° C.