SU552293A1 - The method of producing transition metal hydrides - Google Patents

Description

one

The invention relates to the production of powders of transition metal hydrides and can be used in nuclear power engineering, powder metallurgy, as well as in the technology of atomic hydrogen production.

Known methods for producing hydrides include hydrogenation of metals in furnaces at high temperatures for a long time under harsh conditions 1, 2.

However, with such methods, expensive furnace equipment is used, the hydrogenation technology is complicated, and the hydride is not sufficiently pure and with a low hydrogen content.

The closest in terms of process drying and the result achieved is a method based on the interaction of metal powder with gaseous hydrogen at elevated temperature for 1-12 hours 3.

The aim of the invention is to increase the purity of the transition metal hydrides and their hydrogen content, simplify the instrumentation and speed up the process.

This is achieved by the fact that according to the proposed method, the synthesis is carried out by instantaneous local heating of the metal-hydrogen system to the ignition temperature of the metal.

Preferably, a metal powder with a particle size of 500-1500 microns is used.

Local heating is carried out with the aid of hot tungsten wire or ignition tablets;

Example 1. Polydisperse powdered scandium (with a particle size of 0.5-1.5 mm, in the amount of 10-15 g) is compressed into a tablet and placed in an airtight vessel (bomb) with viewing windows equipped with tubes for entry and discharge and a lid with a glass rack and an electric ignition coil attached to it. The material used for the helix is tungsten wire. Before the start of the experiment, the bomb is evacuated to 10-1 m p st. then it is filled with hydrogen to a pressure of 1-5 atm. Thereafter, the current is supplied to the coil from the network and the mixture is ignited. Synthesis time 1-3 seconds. After cooling, the hydrogen is discarded and the product is removed from the bomb. Analysis and characteristics of the product. Hydrogen content, wt. %:

Based on ScHj4.29

Paved by analysis4,30

X-ray phase data: scandium hydride with a face-centered cubic lattice of the CaFz type with a lattice period of a 4.7809 A.

Example 2. Under the conditions of example 1, yttrium hydride is synthesized from polydisperse yttri powder with a particle size of more than 0.5-1.5 mm.

Analysis and characteristics of the product.

Hydrogen content, wt. %

In the calculation of YH22,21

Found by analysis2,22

X-ray phase data: yttrium hydride with a face-centered cubic lattice of Sar2 type with a lattice period, 2007 A.

Example 3. Under the conditions of Example 1, neodymium hydride is synthesized from polydisperse neodymium powder with a particle size of more than 0.5-1.5 mm.

Analysis and characteristics of the product.

Hydrogen content, wt. %: Based on NdHa1.37

Found by analysis1.35

X-ray phase analysis data: neodymium hydride with a face-centered cubic lattice of Cad2 type with a lattice period, 463 A.

Example 4. Under conditions of example 1, samari hydride is synthesized from polydisperse powdered samarium with a particle size of 300-1500 microns.

Analysis and characteristics of the product.

Hydrogen content, wt. %: Based on SmH21.33

Found by analysis1,32

X-ray phase data: obtained samari dihydride with a face-centered cubic lattice of Sar2 type with a lattice period of 3762 A.

Example 5. Under conditions of Example 1, titanium hydride is synthesized from polydisperse titanium powder with a particle size of 50-1500 microns.

Analysis and characteristics of the product. Hydrogen content, wt. %: Based on TiHa4.04

Found by analysis4.04

X-ray phase data: obtained titanium dihydride with a face-centered cubic lattice of Sar2 type with a lattice period of 4.454 A.

Claims (3)

1. A method of producing transition metal hydrides by reacting a metal powder with hydrogen gas at elevated temperature, characterized in that, in order to increase the purity of the target product and its hydrogen content, to simplify the instrumentation and accelerate the PII process, the synthesis is carried out by instant local heating the metal-hydrogen system to the ignition temperature of the metal. 2. A method according to claim 1, characterized in that metal powder with a particle size is used 500-1500 microns 3. The method according to claim 1, characterized in that the local heating is carried out with the help of red-hot tungsten wire or tablets of the igniting composition. Sources of information taken into account in the examination: 1. Mikheeva V. I. Hydrides of transition metals. M., Publishing House of the Academy of Sciences of the USSR, 1960, p. 30. 2. McKay, K. Hydrogen compounds of metals. M., “Peace, 1968, p. 85. 3. Muller V. Metal hydrides. Atomizdat, 1973, p. 44 (prototype).