SU1668358A1 - Method for obtaining aqueous peracetic acid - Google Patents

Abstract

The invention relates to the production of carboxylic acids, in particular the preparation of an aqueous solution of peracetic acid, used as an epoxidizing and hydroxylation agent, as well as a bleach of cellulose and oils. The goal is to increase the yield of the target product and process performance. It is derived from a reaction mixture containing hydrogen peroxide and acetic acid in a molar ratio of 1: 1, 3 to 5 wt.% Sulfuric and 50 to 60 wt.% Orthophosphoric acid, with further continuous addition of hydrogen peroxide and acetic acid to the reaction mixture. the molar ratio is 1: 1. These conditions increase the productivity of the process by 1.7–3.1 times and increase the yield of peracetic acid by 5–12%. 1 tab.

Description

one

(21) 4713935/04 (22) 05.16.89 (46) 07.08.91. Bul №29 (72) A.E. Batog, G.F. Gavrilin, L.A. Baranovsky, T.V.Savenko, E.N.Samusina, N.P. Kiryushin and A.A. Varivoda

(53) 547.295 39.07 (088.8)

(56) USSR Author's Certificate No. 373269, cl. C 07 C 179 / 12,1972.

Patent of the USSR No. 172698, cl. C 07 C 179/13, 1965.

(54) METHOD FOR OBTAINING AQUEOUS SOLUTION OF A SEPTIC ACID

(57) The invention relates to the production of N-carboxylic acids, in particular the production of

an aqueous solution of peracetic acid used as an epoxidizing and hydroxylation agent, as well as a bleach of cellulose and oils. The goal is to increase the yield of the target product and process performance. It is derived from a reaction mixture containing hydrogen peroxide and acetic acid in a molar ratio of 1: 1.3–5 wt.% Sulfuric and 50–60 May,% ortyphosphoric acid, with further continuous addition of hydrogen peroxide and acetic acid to the reaction mixture. - you are in a 1: 1 molar ratio. These conditions increase the productivity of the process by 1 / 7-3.1 times and increase the yield of peracetic acid by 5-12%. 1 tab.

(L

The invention relates to peracids, in particular, to an improved method for producing an aqueous solution of peracetic acid (NAA), used in the chemical industry as an epoxidizing and hydroxylation agent, and also as a bleach of cellulose oils.

The purpose of the invention is to increase the productivity of the process and increase the output of NAA.

The temperature interval of the process (and the interval of residual pressure values associated with it) is due to the fact that at lower temperatures there is an incomplete condensation of NAFs and their entrainment into a vacuum pump, and at a higher temperature, rapid decomposition of NAA and hydrogen peroxide in a cube is possible.

PRI me R 1. A glass vacuum distillation apparatus was assembled, including a reactor-cube with a capacity of 1 l, equipped with a dropping funnel, a Vigre column 30 cm high, a thermometer, a head for adjusting the degree of reflux distillation, a refrigerator, a Perkin receiver and ice-cooled compilation. A mixture of 81.6 g (1.2 mol) of a 50% aqueous solution of hydrogen peroxide, 72.0 g (1.2 mol) of glacial acetic acid, 500 g of 75% orthophosphoric acid (corresponding to 55% acid content in the mixture) and 28.8 g of 95% sulfuric acid (4% in the mixture). The device is evacuated to a residual pressure of 50 mm Hg. and heat the bottom mixture to 50 ° C. From the moment when the first drop of condensate into the reactor-cube appears in the receiver, using a dropping funnel, start dropping

00 WITH

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give an equimolar mixture of 50% hydrogen peroxide and glacial acetic acid {by 100 May. including peroxide 88.3 May. hours sour, you at a speed of 160 ml / h. a volume velocity of 0.34 s /, with the same rate, the desired NAA solution is distilled off, containing on average 49.1, containing on average 49.1 wt.% peracid.

The productivity of the process in the indicated conditions is 2.44 mol / l.h, its duration using a single bottom mixture is not less than 160 h. The output of NAA per consumed hydrogen peroxide is 98.1%.

PRI me R 2-16. Under the conditions described in example 1, aqueous solutions of NAA are obtained at different temperatures, residual pressure and concentrations of sulfuric and orthophosphoric acids in the bottom mixture. The achieved results are shown in the table. In the table for comparison, the corresponding indicators of the process of example 1 and the known method carried out under optimal conditions are given.

NAA solutions obtained by the proposed method are satisfactorily stable. The concentration of NAA after stabilization of the solutions with the addition of 0.05 wt.% Sodium tripolyphosphate decreases at a rate of 1.2-1.4.

wt.% per day at 20 ° C. The solutions obtained are suitable for epoxidation of alicyclic olefins by known methods.

The proposed method allows to increase the product yield by 5-12% and increase the productivity of the process by 1.7-3.1 times.

Claims (1)

The invention The method of obtaining an aqueous solution of peracetic acid by reacting acetic acid with an aqueous solution of hydrogen peroxide in the presence of an inorganic acid with continuous vacuum distillation of the peracetic acid formed at a reaction mixture of 45-55 ° C and a residual pressure of 40-60 mm Hg, different the fact that, in order to increase the productivity of the process and increase the yield of the final product in terms of consumed hydrogen peroxide, the reaction mixture is subjected to interaction, soda neighing hydrogen peroxide and acetic acid in a molar ratio of 1: 1, 3-5 wt.% sulfuric and 50-60 wt.% orthophosphoric acid, with further continuous addition to the reaction mixture of hydrogen peroxide and acetic acid and a molar ratio of 1 :one. 2, h4 i, 23 2.72 .15, Ь6 I, "1.34 98.1 48.2 1 / .8 95.6 U, 8 94, fi 96.4