RU1297411C - Method for difluorodibrominemethane production - Google Patents

Abstract

The invention relates to halocarbons. in particular the preparation of difluorodibromomethane (CAM). which is used as a fire extinguishing agent and composition ({T of lubricating compositions. An increase in the yield of DBM, expansion of the raw material base and simplification of the process is achieved at other temperature conditions) for the bromination. - 2) and a temperature of 250-350 C. The use of hexafluoropropylene oxide provides the possibility of reducing the catalyst and carrying out g muss at low heating to achieve good yields (up to 90.9%). 1 tab

Description

The invention relates to a method for producing difluorodibromomethane, which is widely used as an effective non-toxic fire extinguishing agent, as a component of lubricating compositions, and also as an important intermediate in organic synthesis,

The aim of the invention is to increase the yield of the target product, expanding the raw material base and simplifying the technological and equipment design of the process, which is carried out at low temperatures without the use of a catalyst.

The process is conducted in the gas phase by continuously passing a gaseous working cMeqn through a flow type reactor; .

PRI me R 1. Pass through the reactor 1 mol of the working mixture, consisting of SzreO / i Br2 at a ratio of 1: 1, at atmospheric pressure, a temperature of 250 ° C and a contact time of 60 s,

The reaction products contain, mol. %: CF2BI-2 14, 1, СрЗСОР 16, СзРеО 34, and Br2 35. The conversion of СЗРаО per pass is 32 mol,%. The yield of SRaVga based on the reacted and missed CzPoO is 87.5 and 28%, respectively.

Example 2. Pass through the reactor 0.15 mol SzRbO and 0.15 mol Br. at atmospheric pressure, a temperature of 280 ° C and a contact time of 25 s. When co version of SzrbO per passage 71.4 mol.% The reaction products contain, mol. %; CFaBr. 27.3, 3.2, CaP i 1.0, СрзСОР35.6, СзРбО М, ЗиВг2 18.5.

. The yield of CPaBa based on reacted and skipped CaFeO is 76.5 and 54.6%, respectively.

Sample The reaction is carried out in excess of Br2. 0.2 mol of GsFeO and 0.4 mol of Br2 are passed through the reactor at atmospheric pressure, a temperature of 280 ° C, and a contact time of 16 s.

When the conversion per passage is 54.7 mol%, the reaction products contain, mol%: СР2Вг2 18.1, 0, СрзСОР 18.9 СзРбО 15.1, and Br2 47.5.

The yield of СР2Вг2 from the calculation of the reacted and missed СЗРбО is 99.3 and 54.3%, respectively.

PRI me R 4. Pass through the reactor 0.76 mol of the mixture, consisting of (it of SLRbO and Bnr At a ratio of 1: 1, at atmospheric pressure, temp8ra7ure 300 ° C and contact time 15 s. With conversion per passage

SBRbO 90 mol% of the reaction products contain, mol%: CP2Br2 31.9, C2P.iBr2 3.5, C2p4 2.1, CFaCOP 43.4, C3F60 5 and Br2 14.1.

The yield of Cp2Br2 based on the reacted and missed CsRbO is 70.9 and 63.8%, respectively.

Example 5. Pass through the reactor 0.27 mol SzrbO m 0.27 mol Br2 at atmospheric pressure, a temperature of 320 ° C and a contact time of 0.5 s.

When the conversion of СзРбО is 22 mol% per passage, the reaction products contain, mol,%: СР2ВГ2 10, С2Р4ВрО, 4, С2Р4 0.1, СрзСОР 10.9, СзРбО 39, and Вр2 39 /}.

The yield of СР2Вг2 based on the reacted and missed СЗРеО is 90.9 and 20%, respectively.

Example 6. Pass through the reactor 1 mol SzRbO and 1 mol Br2 at atmospheric pressure, at a temperature of 350 ° C and a contact time of 0.5 s.

When the conversion of SzrbO per passage 69.8 mol.% The reaction products contain, mol. %: СР2Вг2 24.5, С2РйВг2 2.5, С2Р4 4.8, СрзСОР 33.1, СзРбО 15.1, and ВГ223.

The yield of reacted and missed (the second CzRbO is 70.2 and 49%, respectively.

The material balance data for all examples are given in the table.

At temperatures below 250 ° C, the formation of CP2Br2 proceeds at an insufficient rate, and at temperatures above 350 ° C, the yield of CPaBr2 decreases due to a more significant side reaction.

From the results of the above experiments it is seen that the proposed method for producing CP2Br2 is very effective and allows the process to be carried out at low temperatures 2BO-350 ° C without the use of a catalyst. It is advisable to increase the yield of Br2 in order to increase the yield of CP2Br2.

The by-product CPCCOP formed is a valuable monomer that can be used to prepare, for example, CPCCOOH.

Using the proposed method will simplify the technological and hardware design of the process of obtaining CPaBm.

(56) German Patent No. 2415471, cl. C 07 C 19/08, publisher. 1974.

U.S. Patent Mg 2729687, CL 260-653, 8 published. 1956.

Claims (1)

Formula invented and METHOD FOR PRODUCING DIFFLUORODIBROMMETHANE by bromination of derivatives of lower aliphatic fluorocarbons with bromine at elevated temperature, characterized in that, with Editor N. Timonina Compiled by N.Gazapova Tehred M. Morgenthal Order 3333 Circulation NGO Search for Rospatent 113035, Moscow, Zh-35, Rauska nab .. 4/5 Production and Publishing Plant Patent, Uzhhorod, 101 Gagarin St. In order to increase the yield of the target product and expand the raw material base, hexafluoropropylene oxide is taken as derivatives of lower aliphatic fluorocarbons and the process is carried out at 250 - 350 C with a molar ratio of hexafluoropropylene oxide and bromine 1: {1 - 2). Proofreader L. Fil