SU469484A1 - The method of obtaining granular porous contact - Google Patents

Description

I

The invention relates to the field of preparing norite contacts.

A known method for producing a porous contact based on oxides of refractory metals, includes: mixing the latter with a binder and burnable additives, rolling the resulting mixture onto a core of ashless burning material, drying and calcining the resulting product.

By this method, a uniform composition, the porosity of the granules at the depth of the layer and the reduced mechanical strength of the hollow granules are obtained.

To obtain chemically durable multilayer contact with an adjustable porous structure and chemical composition of individual layers, it is proposed to roll the mixture onto a core of heat-resistant particles in several stages, using the binder containing the binder to the second mixture containing burnable additives in the first stage.

At the same time in the second stage take the mixture, containing 5-35 weight. % of burnable additives, and as heat-resistant particles of the core take particles of irregular shape, for example quartz sand, or granules specially formed from the latter.

The obtained granules are calcined and calcined at 900-1300 ° C.

Example 1. Fine ground quartz sand 98 wt. % mixed with 2% soda. The mixture is rolled onto quartz sand with a grain size of 0.8-1 mm with the addition of sprayed% dextrin solution. The diameter of the granules

1 is adjusted to 3-3.1 mm. Rolling continues using a fine charge of the following composition: 68 weight. % silica sand, 2 wt. % soda and 30 wt. % ash-free petroleum coke.

The diameter of the granules is brought to 5-5.1 mm, the formed granules are dried and calcined at 1100-1200 ° C.

The resulting granules have the following characteristics.

Specific surface area

layer, m / gI-1,5

Specific gravity,, 65

Crush Strength, kg

on the I granule 8-12.

Example 2. Finely ground titanium dioxide 80 wt. % mixed with 20 wt. % clay, for example, watch. The resulting mixture is rolled onto a quartz core 1.5–2 mm in diameter, injecting a 10% solution of sulfite – alcohol bards into the granulator. The diameter of the granules is brought to 3-3.5 mm.

Then the knurling is continued using a mixture consisting of 70% titanium dioxide, 20 wt. % clock of clay and 10%

ashless oil coke. A 3% solution of table glue is used as a temporary binder. The diameter of the granules is brought to 5-5.5 mm.

The granules are dried and calcined for 4-5 hours at 1100-1200 ° C. Characteristics of the obtained granules: ColorGray

Size, mm5-5,5

Specific surface area

layer, m / g2-2,6

Specific gravity, 6

Crush strength, kg per 1 granule7-9.

Subject invention

Claims (3)

1. A method of obtaining a granular porous contact based on oxides of refractory metals, including mixing the latter with a binder and burnable additives, rolling the resulting product onto an impregnated core, drying and calcining the resulting product, in order to obtain mechanically strong multi-layer contact with adjustable the porous structure and chemical composition of the individual layers, the mixture is rolled onto the core of heat-resistant particles in several stages, using a mixture containing binding her, on the second - the mixture containing burnable additives. 2. Method according to n. 1, characterized in that in the second stage a charge is taken containing 5-35 wt. % burnable additives. 3. A method according to claim 2, characterized in that irregularly shaped particles, for example quartz sand, are taken as heat-resistant particles of the core, or molded from the last pellet.