SU779310A1 - Method of producing ferric bromides - Google Patents

Description

(54) METHOD FOR OBTAINING IRON BROMIDE

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This invention relates to a technology for producing iron bromides used in the chemical industry for the production of alkyl bromides and technical bromine.

A known method of producing iron bromides from acidified to pH 2-3 bromine-containing brines, including oxidation of bromide to elemental bromine with chlorine, blowing off bromine with air, absorption of bromine from the gas mixture with a solution of ferrous bromide with iron chips 1.

To clean the absorbing solution from solid impurities, a sludge solution is provided before it is fed to the absorber to absorb bromine, but this technique is ineffective and does not provide the required quality of the solution. The absorption tower is irrigated with a solution at the rate of 4-5 sections of the apparatus, or about 50. The volume of the settling tank of one system is about 30 m. The residence time of the solution in the sump is about 30 minutes. Due to the high viscosity of the solution, its high density, 4-1.6 g / cm) during the indicated time, the solution is not practically released from solid impurities (their content is 2-3 r / ji), which leads to slamming of the nozzle, increase the hydraulic resistance of the absorber and the entire system, reducing air consumption and product yield. When working on contaminated solutions, when the resistance of the absorber reaches 250 mm or more mm of water. Art., the product yield is reduced to 65%, and the total yield even on a partially contaminated nozzle is not

It exceeds 70-75%. Thus, a disadvantage of the known method is the low yield of the product and the efficiency of the process due to the high content of impurities in the solution (2-3 g / l) at the bromine absorption stage.

The purpose of the invention is to increase the yield of the product to 85% and. increasing the process efficiency by reducing the content of impurities in the solution at the bromine absorption stage to 0.02-0.05 g / l.

Goal Achieved A method for producing iron bromides from acidified bromine-containing brines, which consists in oxidizing bromide with chlorine, blowing off bromine with air, 3 taking up the mixture with a solution of acid bromide barely: after the recovery with iron chips, before the procedure, with the treatment, you can get rid of the iron oxide with the metal chips, followed by the treatment with the bourgeois barometer, after the procedure, with the treatment of the iron oxide with the metal chips, before the procedure, the body with the acid will get rid of the bromide with a boring acid, it will be used by the body, it will be replaced with the bourthyme bromide with a solution of oxidized bromide with chromium containing bromide. treated with mineral acid, taken in an amount of 0.02-0.05 g-eq / l, is separated from 0.03-0.05 part of the solution, iron oxide is reduced to oxidized to 80-100%, and The solution is washed for 10-15 hours, the impurities are separated and the clarified part is mixed with the rest of the solution, and as the mineral acid, either sulfuric or hydrochloric or hydrochloric acid or mixtures thereof are used. The introduction of mineral acid into the absorption solution contributes to slowing down the hydrolysis of iron in the process of absorbing bromine from the gas mixture, preventing contamination of the solution and depositing it on the nozzle of the absorber of poorly soluble iron hydroxide and oxybromides; dissolving the fine mist contained in the solution — iron oxides; accelerating the reduction process of iron oxide with iron chips due to the release of atomic hydrogen; 2H + Fe 2H V Fe + 2H Fe + gN If the treatment is carried out with microeralic acid taken in an amount less than 0.02 g-eq / l, the content of solid impurities is enhanced and the product yield decreases. The introduction of mineral acid more than 0.05 g-eq / l is impractical because it does not lead to a decrease in impurities and an increase in the product yield. The process of reducing the recovery of iron oxide bromide is not carried out in the entire solution volume, but only in a part of the solution taken from the total flow circulating, by an amount of 80-100% followed by separation of this solution during at least 10-15 hours It bakes more than the required amount of ferrous bromide with a high degree of purification from solid impurities for carrying out the process of absorbing bromine from the gas mixture. If it is maintained for less than 10 hours, the yield of the product decreases, the recovery is greater than 15 hours, as this does not lead to a further decrease in the amount of impurities in the solution and an increase in the yield. Separation of the solution in bulk, less than 0.03 hours of the total flow of the solution, leads to an increase in the content of impurities in the solution, and in an amount greater than 0.05 hours of the total flow - to the need to increase the volume of the recovery and settling tank. In this method, during the selection of 0.05 hours from the total amount, the 15-hour sludge is provided in a tank with a volume of 20 times less than by a known method.

Claims (2)

ly ffjja jpjbM X - V ---; -;:; -; Reducing iron oxide to soured in solution is less than on U and also Rivo. Dissolve to an increase in the volume of settling capacity and, consequently, to an increase in capital expenditures for obtaining solutions with a high degree of purification from solid impurities. PRI me R 1. The production of 120 kg / h of ferrous and ferrous bromide (calculated as 100% bromine) receives 280 brine containing 0.5 kg / m of bromide. The brine is acidified to a pH of 2.5, treated with chlorine in the amount of 93.5 kg / h, and the bromine from the brine is blown out with a stream of air. The gas mixture is directed to the absorption tower and to the absorption of bromine (also chlorine impurities). The absorber is irrigated with a solution in an amount of 50 m / h containing ReBrg 371, FeBrj 340. The bromide concentration is 550 kg / m. Hydrochloric (sulfuric, hydrobromic) acid is continuously introduced into the solution at the rate of 0.02 g-SQV / l. Hydraulic resistance absorber 100 mm water.st. the entire bromine system is 650 mm of water. with. 330 kg / h of iron bromide are consumed to absorb bromine from the gas mixture, respectively, 452 kg / h of iron oxide bromide are formed. From the total flow of the solution, 1, 2, is taken which is 0.03 of the total flow and is directed to the reduction of ferric oxide to the ferrous oxide. Recovery is carried out at 100%. Spend 52 kg / h of iron - chips. The reconstituted solution is cleaned from solid impurities in a 25 m septic tank. During the 15 hours sludge, the solution is completely free of suspended matter. 0.218 m / h of the solution is taken from the tank and transferred to the production of technical bromine. The remaining amount (1302 m / h) is directed at the offset) {s with the total flow. To stabilize the composition, the same volume of water is introduced into the tank. The product yield for bromine 85%. EXAMPLE 2 Production of ferrous bromide, not containing oxide iron, in an amount of 120 kg / h (based on 100% bromine) is produced from raw materials, as in Example 1. The gas mixture (bromine and an admixture of elemental chlorine ) cleaned of chlorine by contact with a solution of iron bromide, sent to the absorption bait, irrigated with a solution in the amount of 50., containing, kg / m: FeBrz 452.7; ReBhge 265, bromide concentration 550 kg / m. 0.05 g-zcb / l of sulfuric acid (hydrobromic acid) are continuously added to the solution. Hydraulic resistance of the absorber is 100 mm water column, the entire bromine system is 650 mm water column. 330 kg / h of iron bromide are consumed to absorb bromine. 452 kg / h of iron oxomide bromide is formed, respectively. 2.1 m / h is taken from the total solution flow, which is 57. 0.05 hours, the total flow is directed to the reduction of iron oxide to the ferrous oxide. . Consumption of iron shavings 52 kg / h, The recovered solution is cleaned from solid pri The solution is cleaned (residual impurity content 0.02 g / l). 0 is taken from the settling tank, the solution in the form of the finished product. The remaining amount (1.882) is transferred to mixing with the total flow. 0.218 of water is added in. Bromine yield 83%. Prize: 280 brine containing 0.4 kg / m of bromide is supplied to produce 96 kg / h of ferrous and ferrous bromide (calculated on 100% bromine). The brine is acidified to a pH of 2.5 and treated with chlorine in an amount of 75 kg / h, and the bromine from the brine is blown out with a stream of air. The gas mixture is directed to absorption for absorption of bromine. 20 Absorber is irrigated with a solution in an amount of 50 containing, ReВг2 452.7: ReВгз 265.5, bromide concentration 550 kg / m. Hydrochloric acid is continuously added to the solution at a rate of 0.03 g-sqv / l. The hydraulic resistance of the absorber ON mm water. Art., the entire system - 660 mm of water. Art. 64 kg / h of bromine iron are consumed to absorb bromine from the gas mixture, and 362 kg / h of iron oxide bromide, respectively, is formed. From the total flow of the solution, 2.0 m / h is taken, which amounts to 0.04 part of the total flow and is directed to the reduction of ferric oxide to ferrous. Recovery is carried out at 90%. Consume 41.6 kg / h of iron shavings. The reconstituted solution is cleaned of solid impurities in a 25 m settling tank. Over a period of 12.5 hours, the solution is completely clarified and transferred for mixing with the total flow into an alkaline tank. 0.174 m / h of the finished product is taken from the tank and transferred to the production of technical bromine; 1,826 m / h return on offset. To stabilize the composition, the same volume of water is introduced into the tank. The product yield for bromine 83%. Using this method provides compared with the known increase in product yield by 3-5%; increasing the efficiency of the process by reducing the solids content from 2-3 to 0.02-0.05 g / l; a decrease in the hydraulic resistance of the absorber by preventing or abruptly lowering and dropping the nozzle from 250-300 to 80-100 mm of water. Art. Claim 1. Method for producing iron bromides from acidified bromine-containing brines, including oxidation of bromine with chlorine, blowing out rum with air, absorption of bromine from the gas mixture with a solution of ferrous bromide with iron chips, characterized in that, in order to increase the yield; product and increase the efficiency of the process by reducing the content of impurities in the solution at the stage of absorption of bromine, before the absorption of bromine, the solution of the bromide of ferrous jelly is treated with the mineral In flax acid, taken in an amount of 0.02-0.05 g-eq / l, 0.03-0.05 parts of the solution is separated, the iron oxide is reduced to oxidized to 80-100%, the solution is 10- 15 hours, the impurities are separated and the clarified portion is mixed with the remaining solution. 2. The method according to p. 1, that is, with the use of either sulfuric or hydrochloric or hydrobromic acid or their mixtures as a mineral acid. Sources of information received in BHMMairae during examination 1. Regulations for the production of iron bromide at Cheleken chemical plant No. 3, Chelekent. 1976.