SU979516A1 - Method for preparing alkali metal selenides - Google Patents

Description

(54) METHOD FOR OBTAINING ALKALINE METAL SELENIDS

one

The invention relates to the production of rare metals and can be used in non-ferrous metallurgy and chemical industry, aimed at extracting chalcogens from concentrates and semi-products.

Alkali metal selenides possess a number of properties that determine their potential for technological application. They are well soluble, in water, and, when aerated, the solution decomposes with the release of elemental selenium in the form of well-filtered crystalline powders.

There are enough methods for producing alkali metal selenides, for example, thermal or autoclave reduction of selenium-containing alkali salts 1.

However, the complexity of the hardware design did not allow these applications to be used in industry. According to this method, potassium or sodium selenides are obtained by dissolving the selenium cathode in solution

Schelovd concentration of 50-200 g / l. This method of industrial application was not found due to the difficulty of preparation - the selenium cathode.

The closest to the proposed technical essence and the achieved effect is a method of better alkali metal settling, including the treatment of selenium with an alkaline solution of 1m with the introduction of a reducing agent. Aluminium powder is used as a reducing agent in this method. The resulting sodium selenide solution is sent to aeration, resulting in selenium 2.

The disadvantage of this method is that

15 that the reducing metal is aluminous, is concentrated in the water of the sodium apum sodium and upon saturation, the sugar is released as padroxide, which is sent to the dump and stored. The amount of hydroxide by weight is twice the commercial product - selenium.

Claims (2)

The purpose of the invention is waste disposal. 397 The goal is achieved by the fact that according to the method of obtaining alkali metal selenides, including the treatment of selenium with an alkaline solution with the introduction of a reducing agent and subsequent purging with air, the process is carried out with the introduction of formate into the solution as a reducing agent of organic compounds sodium or glucose. The choice of organic reducing agents is due to the fact that the final products of the reaction are carbon dioxide and water, accumulation of extraneous ions in the solution does not occur. From tested organic reducing agents, a positive effect is obtained using sodium formate and glucose. Example 1. In 100 ml of a solution with a NaOH concentration of 100 g / l, 10 g of elemental selenium are otremulgiruyut, then 10 g of sodium formate at 90 ° C are introduced. jiO: As a result, 9.62 g of selenium goes into solution. , Example 2. In 100 ml of a solution with NaOH concentration 100 g / l, 10 g of elemental selenium are rationed, then 8 g of glucose are introduced at 90 ° C. The dissolution of selenium with the formation of sodium selenide proceeds by the reaction:, Oj , + 2NaOH- Na- Se + HjO As a result, 9.76 g of selenium is transferred to the solution. The present invention allows the process to be carried out without the formation of intermediates, which are dumps in a known method. Claim 1. Method for producing alkali metal helenides, which includes treatment of selenium with a pinch solution with the introduction of a reducing agent and subsequent blowing with air, characterized in that, in order to eliminate waste, the process is carried out with the introduction of organic compounds into the solution as a reducing agent. 2. The method according to p. I, of tl and h a y y and yc. by the use of sodium formate as a reducing agent. 3. The method according to claim 1, which is based on the fact that glucose is used as a reducing agent. Sources of information taken into account in the examination 1. US Patent No. 2414438, cl. 75-88, 1947. 2. USSR author's certificate number 165309, cl. From 22 to 61/00, 1964.