SU1452791A1 - Method of producing hypovanadates of bivalent metals - Google Patents

Abstract

The invention relates to a method for producing divalent metal hypovanadates of the composition, where M is Mg, Ca, Mn, and allows reducing the temperature and simplifying the process. A mixture containing 22.2-23.8 g of one of the metavanadates of the composition, or 12.6 g (molar ratio MV404: NajS03 1: 1), no-i is placed in an atmosphere of argon and calcined at 500-650 s for 2-8 hours. After that, the mixture is cooled to room temperature, washed with water, air-dried and analyzed. The products obtained, according to this X-ray phase and chemical analyzes, correspond to single-phase hy- vanadates of the composition MgV205-, and. a tg l

Description

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This invention relates to methods.

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production of divalent metal hypovanadates with the composition MVjOy, where M is magnesium, kalydai, manganese, which can be used as catalysts and in electrochemical devices.

The purpose of the invention is to reduce the process temperature and simplify the process by eliminating ampoule synthesis.

Example 1. A mixture of 22.22 g of MgVjO and 12.60 g was placed in an argon atmosphere and calcined for 8 hours. After that, the mixture was cooled to room temperature, washed with water and dried in air. According to X-ray phase and microscopic analyzes, a single-phase sample is obtained.

The mass gain during oxidation in air is determined and is equal to 7.13 wt.%. The theoretical mass gain is 7.20 wt.%.

Example 2. The process is carried out as in Example 1 for 2 hours. A single phase sample is obtained.

MgViOy. The mass gain during oxidation is 7.16 wt.%.

Example 3. A mixture of 23.80 g of CaVjOj and 12.60 g is placed in an argon atmosphere and calcined for 8 hours. After that, the mixture is cooled to room temperature, washed with water and dried on air. D3 | He, According to X-ray and microscopic analysis, a single-phase sample is obtained. The mass gain during oxidation in air and 600 ° C is determined to be 6.68 wt.%. Theoretically, 6.73 wt.%.

Example 4. The process is carried out as in Example 3 for 5 hours. A single phase sample is obtained. The weight of the mass in the oxidation of 6.66 wt.%.

Example 5. A mixture of 22.08 g and 12.6 g of Na / jSOj is placed in an argon atmosphere and calcined at 550 ° C for 8 hours. After that, the mixture is cooled to room temperature35

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The temperature of the proposed method is 1.5 times lower than that by a known method, which allows reducing the energy costs in the synthesis of hypovanadates. The advantage of the proposed method is the possibility of obtaining compounds of a given state under production conditions. The resulting compounds are finely dispersed (particle size less than 10 µm), which will have a positive effect on the manufacture of ceramic products from them (due to better sintering properties). Moreover, the proposed method guarantees the production of compounds with this oxygen composition, which is confirmed by a 100% yield reaction products.

Claims (1)

Invention Formula The method of obtaining bipolar metal hypovanadates of the composition, where M is magnesium, calcium or manganese, including calcining vanadium oxide compounds of metals in an oxygen-free atmosphere, in order to reduce the temperature and simplify it by eliminating ampoule synthesis, As the initial ocean-containing compound, the metavanadate of composition MV is used. .... tours, washed with water and dried-on the skin before calcining five 0 five ABOUT five 0 five 0 The mass gain during oxidation in air is determined and is equal to 6.28 wt.%. Theoretically, 6.32 wt.%. Example 6 The process is carried out as in Example 5 for 2 hours. A single phase sample is obtained. Pick up the mass during the oxidation of 6.30 wt.%. A ratio of 1: 1 and a process time of 2-8 hours is selected, on the basis of the need to obtain a single-phase product of the claimed composition j. Thus, the implementation of the invention allows to simplify the process in hardware and technology relations, since it is carried out at atmospheric pressure in an inert gas. According to a known method, complex ampoule technology and special conditions are required when working with hygroscopic calcium oxide. The temperature of the proposed method is 1.5 times lower than that by a known method, which allows reducing the energy costs in the synthesis of hypovanadates. The advantage of the proposed method is the possibility of obtaining compounds of a given composition under production conditions. The resulting compounds are fine (particle size less than 10 µm), which will have a positive effect in the manufacture of ceramic products from them (due to better sintering properties). In addition, the proposed method guarantees the production of compounds with a given composition in oxygen, which is confirmed by the detected 100% yield of the reaction products. Invention Formula A method for producing bipolar metal hypovanadates of the composition, where M is magnesium, calcium or manganese, including calcining vanadium oxide compounds of metals in an oxygen-free atmosphere, in order to reduce the process temperature and simplify it by eliminating ampoule synthesis, as the starting ocean-containing compound. use metavanadate composition,