SU981226A1 - Process for producing arsenic acid - Google Patents

Description

(54) METHOD FOR OBTAINING MUSCLE ACID

The invention relates to a process for the production of inorganic substances, in particular, mouse acid, which is the starting material for the production of metal arsenates. and mouse of organic compounds.

A method of producing mouse acid is known by oxidizing arsenic trioxide with a 30-35% solution of hydrogen peroxide, which is calculated on the basis of 110%. ot the theoretically required amount. Arsenic trioxide and water are fed to the reactor, b the reactor jacket is supplied with hot steam, the mixture is heated to boiling for 30-40 minutes, then it is stopped, the steam is supplied under conditions of cold water flow into the reactor jacket, and 30-35% is added. Hydrogen peroxide The optimum temperature for the oxidation of a white mouse is 60-70 ° C. After adding a given amount of hydrogen peroxide, the reactor is slowly heated for 20-30 minutes. Then: Water is added to the reactor and boiled for 2-3 hours. This method produces an acid with a concentration of 45-50%, the frequency of which depends on

purity of starting mouse trioxide Cl.

The disadvantages of this method are the high consumption of hydrogen peroxide (requires a 10% excess of the theoretically required amount) and the duration of the process

(6-8 h).

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The closest to the proposed technical essence and the achieved result is a method of obtaining molar acid by oxidizing, arsenic trioxide with a dilute solution of hydrogen peroxide. For the reaction Use of high purity mouse trioxide or pharmacopeia and oxidant g of hydrogen peroxide (medical) 1020 20% concentration, which is taken from the calculation of 110-150% of the theoretically required amount. The process is carried out in a stainless steel reactor at 95-98 ° C, oxidation ends after 22-45 minutes. The concentration of the resulting acid is 29-35% 2.

The disadvantages of this method are the high consumption of water-type peroxide (a 10-50% excess is needed

30 theoretically required quantity and the concentration of the product is not high enough. The aim of the invention is to reduce the consumption of hydrogen peroxide and increase product concentrations. This goal is achieved by the fact that according to the method of obtaining mouse acid, acyclic cemus, in the oxidation of compounds containing trivalent mouse, using hydrogen peroxide, trialkylarsenites of the general formula carbon. Example It. Preparation of arsenic acid by the oxidation of tri-n-amylarenite. To 336.0 g (1 mol) of three-n-si 1-ilarsenite, while stirring and cooling with running water, slowly (over 30 minutes) add 226.0 g 15% (1 mol ) an aqueous solution of hydrogen peroxide. After 5-10 minutes of heating to remove traces of hydrogen peroxide and cooling, the aqueous layer is separated and the alcoholic layer is extracted 3 times with water (30 ml total). 319.6 g (or 236.0 ml) are obtained 42.5% solution of mouse acid (d 1, -352). The yield of the desired product is 95.6%. Organic chemistry is also extracted, from which distillation gives amyl alcohol from 95-98% yield. Examples 2-5 are carried out analogously to example 1. The results are shown in the table.

For quantitative oxidation of trialkylamine, a 10-15% solution of hydrogen peroxide is optimal, preferably a 15% solution is more preferable. Only an equivalent amount of hydrogen peroxide is required for oxidation. When using a more concentrated solution of hydrogen peroxide, in addition to the oxidation of ion (xy), other parallel reactions take place in the mouse (y), as a result of which the oxidant is additionally consumed. In addition, a homogeneous mixture is formed, from which the selection of the target product is associated with such unequal difficulties, while the yield of the target product is reduced.

Thus, the proposed method allows to reduce the consumption of hydrogen peroxide (instead of 10-50% excess versus the theoretically required amount, take the amount needed only by stoichiometry) and increase the product concentration from 29-35% to 41.5-55, 0%. In addition, in the process described, the corresponding alcohol is quantitatively regenerated; the separation of the kogoggb from the target product is easily achieved

and which can be re-applied in order to obtain the starting component, trialkylamine, and also get a cleaner mouse, since the starting trialkylamine is highly pure.

Claims (2)

1. Achievements of veterinary helminthology- w practice. Tbilisi, Publishing House Sabchot Sakartvelo, 1971, p. 88 2. USSR Author's Certificate No. 510430, cl. Since 01 G 28/00, 3 d. Vl. 1974 (prototype).