Electric cast mullite brick and preparation method thereof

Abstract

The invention relates to an electric cast mullite brick, which comprises the following raw materials with the granularity distribution in percentage by weight: 55 to 80 percent of electric cast mullite with the granularity distribution being smaller than or equal to 3.5mm, 10 to 20 percent of kyanite with the granularity distribution being smaller than or equal to 0.1mm, 10 to 20 percent of quartz with the granularity distribution being 0.1 to 1.5mm, 0 to 5 percent of clay with the granularity distribution being smaller than or equal to 0.1mm and 0 to 1 percent of titanium dioxide with the granularity distribution being 2 to 10mum. A preparation method of the electric cast mullite brick comprises the following steps that: crushing, sieving and magnetic separation are carried out; the kyanite, the quartz, the clay, the titanium dioxide and partial electric cast mullite are mixed with oleic acid and are subjected to ball milling to obtain ball milling materials; bonding agents are dissolved in water to be mixed with the rest electric cast mullite to obtain particle materials; the ball milling materials and the particle materials are mixed and are subjected to mixed milling, aging decaying and secondary mixing; green bricks are obtained through pressure forming, and the green bricks are dried and fired. The electric cast mullite brick and the preparation method have the advantages that the process is simple, the cost is low, the operability is high, and the obtained electric cast mullite brick body has high density, good acid resistance, high normal-temperature bending-resistant intensity and excellent thermal shock stability.

Description

technical field [0001] The invention relates to the technical field of refractory materials, in particular to a refractory brick prepared with fused mullite as the main material. Background technique [0002] When preparing anatase-type pure titanium dioxide in a high-temperature fluidized bed reactor chlorinator, the natural titanium dioxide ore is crushed and mixed with other ingredients, chlorination reaction generates gas-phase titanium tetrachloride, and then the titanium tetrachloride is separated and purified, and in In the subsequent reaction, it reacts with oxygen to form pure titanium dioxide. In the chlorinator, the temperature of the fluidized bed reactor is as high as 1200° C. After the chlorine gas is introduced, it also contains a high concentration of HCl, the internal environment is very bad, and the brick body of the chlorinator is very corrosive. [0003] If the compressive strength of the bricks of the chlorinator is low, it will cause the bricks to crac...

AI Technical Summary

Problems solved by technology

[0004] At present, the special bricks for titanium dioxide fluidized bed reactor chlorinators are mainly produced by British Morgan Thermal Ceramics (RESCO), and the market price is expensive. The mullite phase of the bricks (80D) produced by them is only 60~70% (chemical analysis Al 2 o 3 Content 45.8%, SiO 2 Content 50.5%), the bulk density is low (2.419g / cm 3 ), low compressive strength at room temperature (82.7MPa), low flexural strength (17.2MPa), so it is not ideal for use

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