RU2713362C1 - Method of producing titanium tetrachloride - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention relates to a method of producing titanium tetrachloride and can be used in production of titanium sponge and pigment titanium dioxide. Titanium tetrachloride is obtained by chlorination of titanium-containing materials in the apparatus with a boiling layer of crushed titanium-quartz concentrate and carbon with supply of chlorinating gas at temperature 700–1,000 °C. Simultaneously with the chlorinating gas evaporated titanium tetrachloride is supplied to the bottom of the apparatus.

EFFECT: enabling increase in the target titanium tetrachloride removal from the reaction volume unit, id est high efficiency of the reaction apparatus.

1 cl, 4 ex

Description

The invention relates to a method for producing titanium tetrachloride by chlorination of mineral titanium-containing raw materials in a fluidized bed reactor, and can be used in the technology of producing titanium sponge and pigment titanium dioxide.

A known method of producing titanium tetrachloride by chlorination of titanium mineral raw materials in shaft reactors (Zelikman A.N., Korshunov B.G. Metallurgy of rare metals. M: Metallurgy, 1991, S. 170-173). In mine reactors, briquettes are subjected to chlorination, which are obtained by mixing titanium mineral raw materials and petroleum coke (20-25 wt.%). A binder, for example, sulphide-cellulose liquor, coal tar or petroleum pitch, is added to the mixture. The resulting mixture is pressed on roll presses into pillow-shaped briquettes of size 50 × 40 × 35 mm. In order to increase viciousness and remove volatile substances, briquettes are calcined without air at 850-950 ° C in special furnaces.

The disadvantages of this method are:

- a complex technology for the preparation of feedstock, requiring the use of auxiliary substances and high-temperature calcining of the resulting briquettes, and, as a result, high costs that increase the cost of the resulting titanium tetrachloride;

- high explosive risk of exhaust gases due to the predominance of carbon monoxide in them.

- low rate of chlorination of titanium compounds, as the process proceeds in the internal diffusion region.

Closest to the claimed method is a method for producing titanium tetrachloride by chlorination with gaseous chlorine of crushed particles of mineral raw materials containing titanium dioxide with a particle size of more than 325 mesh (0.044 mm), as well as carbon particles, while chlorination is carried out in a fluidized (fluidized) layer ( U.S. Patent No. 2,555,374 of November 2, 1949).

The disadvantage of this method is the low removal of titanium tetrachloride per unit reaction volume.

An object of the invention is to increase the removal of titanium tetrachloride from a unit of the reaction volume.

This problem is solved by feeding (recycling) titanium tetrachloride in a fluidized bed in the lower part of the chlorination reactor.

Examples illustrating the method:

Example 1 (prototype).

The chlorination process was carried out in a laboratory setup, including a fluidized bed reactor, a quartz condenser and a glass quenching column. The fluidized bed reactor - a quartz apparatus with a diameter of 30 mm and a height of 200 mm - is equipped with a conical gas distributor, electric heating, a sleeve for a thermocouple and a fitting for unloading solid reaction products. The reaction volume was 105 cm ³ .

A titanium-quartz concentrate with a grain size of -0.25 + 0.16 mm (60 mesh) was chlorinated. The grain size of petroleum coke is 0.4 + 0.16 mm (~ 40 mesh). Titanium-quartz concentrate had the following composition (in terms of oxides of elements): TiO ₂ - 49.53 wt. %; SiO ₂ - 45.20 wt. %; Al ₂ O ₃ - 2.9 wt. %; Fe ₂ O ₃ - 1.36 wt. %; others - 1.01 wt. % The molar ratio of carbon: titanium dioxide = 1: 5. The chlorination temperature is 900 ° C. The linear velocity of chlorine is 0.067 m / s. The experiment time is 50 minutes. The removal of titanium tetrachloride was 1051.4 g per 1 liter of reaction volume per hour.

Example 2 (prototype)

At the installation and under the conditions described in example 1, titanium-quartz concentrate with a grain size of -0.63 + 0.16 mm was chlorinated.

The titanium tetrachloride content was 401.2 g per 1 liter of reaction volume per hour.

Example 3

The process of chlorination of titanium-quartz concentrate was carried out on the apparatus and under the conditions described in example 1. The difference was that together with chlorine, pre-evaporated titanium tetrachloride in the amount of 12% mol was fed into the reactor. from the supply of chlorine. As a result of the reaction, the removal of titanium tetrachloride amounted to 1279.3 g with 1 liter of reaction volume per hour, excluding titanium tetrachloride supplied with chlorine.

Example 4

The process of chlorination of titanium-quartz concentrate was carried out on the apparatus and under the conditions described in example 2. Together with chlorine, pre-evaporated titanium tetrachloride in an amount of 12.5% mol was fed into the reactor. from the supply of chlorine. As a result of the reaction, the removal of titanium tetrachloride amounted to 512.4 g with 1 liter of reaction volume per hour, excluding titanium tetrachloride supplied with chlorine.

An analysis of the data presented in examples 1-4 shows that feeding the pre-evaporated titanium tetrachloride simultaneously with the chlorine to the bottom of the reactor leads to an increase in the removal of target titanium tetrachloride from a unit of the reaction volume, i.e. to increase the productivity of the fluidized bed reactor. The effect of increasing the removal of the target product is observed regardless of the grain size of the titanium-quartz concentrate.

Claims (1)

A method of producing titanium tetrachloride, including chlorination of titanium-containing materials in a fluidized bed apparatus of crushed titanium-quartz concentrate and carbon with the supply of chlorinating gas at a temperature of 700-1000 ° C, characterized in that titanium tetrachloride is simultaneously fed to the bottom of the apparatus.