SU559897A1 - The method of producing alkali metal fluorobromates - Google Patents

Description

one

This invention relates to a process for the preparation of alkali metal fluoro-boiled mattes used as strong fluorinating agents.

A known method for producing metal fluoride aromates, for example barium, by mixing metal fluoride with bromine trifluoride, taken in a stoichiometric ratio. The resulting mixture is heated to 100 ° C and the desired product is isolated.

There is also known a method for producing alkali metal fluorobromates of the CsBrF.i. Type (or CsF-BrFs) by reacting cesium fluoride and bromine trifluoride. The monolayer reactor, previously passivated with chlorine rifluoride, is loaded with cesium fluoride H purified from hydrogen fluoride, bromine trifluoride, taken in excess. The reagent ratio in the feed is 1: 2.6. The reactor is sealed, the mixture is heated to 80 ° C and maintained at this temperature for 12 days with continuous stirring of the reactants. Unreacted bromine trifluoride is removed under vacuum at 50 ° C. A micro-crystalline product is obtained with a CsF ratio; BgPz 1: 1, .01.

FIELD OF THE PRIOR ART is the impossibility of producing alkali metal fluorobromates of the type MeF-2BrF3, the need for pre-purification of trifluoride

bromine from hydrogen fluoride and the duration of the process.

In order to eliminate these drawbacks, it has been suggested that irocss be conducted in the presence of hydrogen fluoride, taken in an amount of 5–10% by weight of bro.ma trifluoride, at a temperature of 40–70 ° C. In this case, the starting compounds are taken in molar.m ratio of 1: 1.2-5.0, mainly I: 2.

These differences allow you to receive

alkali metal fluorobromates of the type MeF2BrF3 and shorten the process time.

Example I. In hermetically sealed

Fluoroplastic reactor with a volume of 30 cm is charged with 15.2 g of cesium fluoride. The reactor is evacuated and then 30 g of the mixture of bromine trifluoride with hydrogen fluoride fluoride (27.4 g of BrFs and 2.6 g of liF) are introduced into it. The reactor is heated

to 50 ° C and maintained at this temperature. 30 min. Then the mixture is cooled to room temperature within 30 minutes. Transparent, prismatic crystals measuring 1 mm are obtained. Excess solvent is removed under vacuum. 42.2 g of product are obtained.

composition, weight. %: Br 37.35; Cs; 3 {, 52; F 31.13.

Calculated for CsF-2BrF3, weight%: Br 37.53;

Cs 31.21; F 31.24; The product yield is 99%.

Example 2. 10.5 g of pre is loaded into the reactor from fluoroplastic;

rubidium fluoride. The reactor is cooled to 0 ° C and TIO is added to it in drops: 27: 4 g of bromine trifluoride and 1.0 g of hydrogen fluoride. The mixture is heated to 70 ° C for 30 minutes with stirring. Obtain 29.5 g of prol.ukta in the form of large transparent crystals of a prismatic form with the content, weight. %: Rb 22.20; Br 42.57; F 35.0. Calculated for addr.2VgRz, weight. %:, Rb 22.59; Vg. 42,27; F 35.14. The yield of 78%.

Claims (2)

Claim 1. Method for producing alkali metal fluorobromates by reacting fluoride alkali metal bromine trifluoride with heating, characterized in that, in order to obtain compounds of composition MeF2BrH3, where Me is rubidium or cesium alkali metal, and to simplify the process, the process is carried out in the presence of hydrogen fluoride, taken in an amount of 5-10% of the weight of bromine triforide, at a temperature of 40-70 ° C. 2. A method according to B. 1, characterized in that the starting compounds are taken in a molar ratio of 1: 1.2-5.0, preferably 1: 2.