Creation With the Zinc Selenide Now for Your Requirement Now

The invention can be used in the chemical industry. A method for processing zinc selenide waste comprises oxidizing zinc selenide at atmospheric pressure in a solution of ammonium peroxodisulfate at a concentration of 35-37% at a temperature of 70-90 ° C. Next, the resulting crude selenium is purified by a sulphite-cyclic method. The invention makes it possible to use zinc selenide without waste, and to simplify the processing of zinc selenide waste generated in the manufacture of materials in a semiconductor technique, thereby obtaining selenium in one step with a yield of 85-95%.

The invention relates to inorganic chemistry and concerns the development of a method for processing zinc selenide waste generated in the manufacture of materials in semiconductor technology.

Prior Art

A method is known for processing zinc selenide by oxidation with oxygen, followed by condensation of the resulting selenium dioxide vapor. The disadvantage of this method of processing is the complexity of the technological process and hardware design.

A method for the production of selenium dioxide is known, including oxidation with nitric acid, evaporation of the resulting solution and separation of selenium dioxide and purification of the latter by dissolving in sulfuric acid with a concentration of 70-95% and then isolating the desired product from the solution by increasing the sulfuric acid concentration to 99-100%.

The disadvantage of this method is the low quality of the product obtained

The method closest to the technical essence achieved by the positive effect and accepted by the authors for the prototype is the method for obtaining high-purity selenium dioxide by oxidation of zinc selenide at atmospheric pressure, followed by the condensation of selenium dioxide vapor. Oxidation of zinc selenide is carried out in two stages simultaneously by two streams of oxygen, in the first stage the oxidation of zinc selenide is conducted by an oxygen stream at a temperature of at least 300 ° C, and the second stage – the oxidation of the volatile products formed in the first stage at a temperature of not less than 600 ° C.

The Production of Selenium

To produce selenium from the selenium and selenious acid dioxide formed in the second stage of oxidation, it is necessary to carry out their reduction, for example, with sulfur dioxide, and then purification of selenium by known methods, for example sulfite cyclic, which complicates the process. It is impossible to obtain selenium by this method in one step.