RU-2861363-C1 - METHOD FOR SEPARATING WORKING SOLUTION IN PRODUCTION OF HYDROGEN PEROXIDE BY ANTHRAQUINONE METHOD

Abstract

FIELD: hydrogen peroxide production. SUBSTANCE: invention relates to separating a working solution from a hydrogen peroxide solution in the process of producing hydrogen peroxide by hydrogenating alkylanthraquinone in the presence of a hydrogenation catalyst in a working solution medium, followed by oxidising the obtained alkylanthrahydroquinone with an oxygen-containing gas, aqueous extraction of peroxide from the reaction mass from the oxidation stage, separating the working solution, regenerating it and returning it to the cycle. The working solution contains aromatic hydrocarbons, tetrabutylurea and trioctyl phosphate. Before aqueous extraction of hydrogen peroxide, an organosilicon liquid in an amount of 0.01-0.15 mas.% of the weight of the initial working solution is introduced into the reaction mass from the oxidation stage, and the extraction process is carried out at a temperature of 40-50°C. EFFECT: reducing the amount of residual water in the working solution after separating the aqueous hydrogen peroxide solution from the stage of aqueous extraction of hydrogen peroxide from the working solution. 2 cl, 1 tbl, 11 ex

Inventors

• EFIMOV YURIJ TIMOFEEVICH

Dates

Publication Date

20260505

Application Date

20251105

Claims (2)

1. 1. A method for separating a working solution from a hydrogen peroxide solution in the process of obtaining hydrogen peroxide by hydrogenation of alkylanthraquinone in the presence of a hydrogenation catalyst in a working solution containing aromatic hydrocarbons, tetrabutyl urea, trioctyl phosphate, followed by oxidation of the obtained alkylanthrahydroquinone with an oxygen-containing gas, aqueous extraction of peroxide from the reaction mass from the oxidation stage, separation of the working solution with its subsequent regeneration and return to the cycle, characterized in that before aqueous extraction of hydrogen peroxide, an organosilicon liquid is introduced into the reaction mass from the oxidation stage in an amount of 0.01-0.15% by weight of the mass of the initial working solution, and the extraction process is carried out at a temperature of 40-50°C.
2. 2. The method according to paragraph 1, characterized in that the organosilicon liquid is preferably a polyethylsiloxane liquid or a polyphenylmethylsiloxane liquid.

Description

The invention relates to the production of hydrogen peroxide by a two-stage cyclic anthraquinone process, which typically involves hydrogenating a working solution of anthraquinone in a catalytic reactor, oxidizing the working solution of the hydrogenated anthraquinone with air in a multistage packed or sieve column, and simultaneously forming hydrogen peroxide in an organic stream. The working solution contains anthraquinone and a hydrocarbon solvent. Mixtures of two types of solvents are typically used as the solvent: non-polar aromatic compounds for anthraquinone, such as alkylated benzene, and organic polar water-immiscible solvents for anthrahydroquinone, such as tri- and/or tetraalkyl urea, and phosphorus-containing organic substances, such as tris(2-ethylhexyl) phosphate. During the hydrogenation stage, metals selected from among nickel, palladium, platinum, rhodium, ruthenium, gold, silver, or mixtures thereof are used as catalysts. Preferred metals are palladium and platinum, with palladium or mixtures containing at least 50% palladium by weight being particularly preferred. The hydrogen peroxide obtained in the oxidation step is then removed from the working solution, usually by extraction with water, and the remaining working solution, containing alkylanthraquinones, solvents and residual water, is dried and returned to the hydrogenation step or regenerated and then returned to the hydrogenation step. After the stages of the specified main process, other additional process stages may be carried out, such as separation of the hydrogenation catalyst from the working solution; extraction and final purification of the working solution and the corresponding solvents and their recirculation to the hydrogenation device; extraction and final purification and stabilization of the target product - hydrogen peroxide. Due to constant circulation, unwanted impurities from side reactions, such as various quinones (epoxides), accumulate in the working solution. To reduce their amount, the working solution is regenerated. Known methods for regenerating the working solution generally involve contacting the working solution with alkaline solids, such as activated alumina, magnesium oxide, and sodium aluminosilicates. For example, the working solution is regenerated in two columns filled with aluminum oxide (AL 2 O 3 ) , operating alternately. While one column is regenerating the working solution, the other is reloading the aluminum oxide or in reserve. Moreover, one of the main requirements in the technology of producing hydrogen peroxide using the anthraquinone method is the practical absence of water (no more than 0.3%) in the working solutions, including those sent for regeneration and those returned to the hydrogenation stage of alkylanthraquinones. Excess moisture in the working solution leads to loss of activity of the hydrogenation catalyst. Therefore, removing excess moisture from the working solution after extraction is necessary for the catalyst to function effectively during hydrogenation. This allows the process to be carried out at lower temperatures, which in turn leads to a reduction in side reactions and an increase in the yield of the target product. In addition, the increased water content in the working solution also complicates its regeneration on the active layer of aluminum oxide and reduces the operating time of the layer. Therefore, the working solution after extraction of hydrogen peroxide with water is subjected to drying, since after extraction and separation of the aqueous solution of hydrogen peroxide, the working solution usually contains more than 0.35% by weight of water, in connection with this, the production technology usually provides for its drying (for example, evaporation of water under vacuum). A method for producing hydrogen peroxide using the anthraquinone cyclic process with regeneration of the working solution and its return to the cycle is known (PL208465, November 13, 2007). According to this method, the working solution after the hydrogenation stage is passed through Al 2 O 3 , washed with water, the organic phase is separated, mixed with the working solution from the oxidation stage from which hydrogen peroxide has been extracted, and sent to a water removal operation before recycling. The disadvantages of this method include the fact that excess water is removed from the working solution after its regeneration, which leads to a rapid loss of activity of Al 2 O 3 . The objective of the proposed method is to reduce the amount of residual water in the working solution after separating the aqueous solution of hydrogen peroxide from the stage of aqueous extraction of hydrogen peroxide from the working solution. This problem is solved by adding an organosilicon liquid to the oxidized working solution before hydrogen peroxide extraction, at a rate of 0.01-0.15% of the initial working solution's mass, and conducting the extraction process at a temperature of 40-50°C. Polyet