Beta-silicon carbide crystal whisker preparation method

Abstract

The invention provides a beta-silicon carbide crystal whisker preparation method, which comprises: (1) uniformly mixing a silicate-containing silicon source and water glass, and carrying out a reaction to obtain a mixed sol; (2) adding a carbon source to the mixed sol obtained in the step (1), mixing to prepare a wet gel, carrying out standing aging, and drying to obtain a dry gel precursor; (3) carrying out a carbothermal reduction reaction on the dry gel precursor obtained in the step (2) to obtain crude silicon carbide; and (4) removing impurities from the crude silicon carbide obtain the in the step (3) to obtain the beta-silicon carbide crystal whisker. According to the present invention, by combining fly ash, coal gangue and other industrial waste or silicon-rich silicate mineral andwater glass, the reuse of waste materials and the resource utilization and high value utilization of minerals are achieved, and the method has good economy and environment benefits.

Description

technical field [0001] The invention belongs to the field of resource utilization of industrial solid waste and the invention of new ceramic materials, and relates to a preparation method of β-silicon carbide whiskers. Background technique [0002] Fly ash is a kind of solid waste produced by coal-fired power plants. With the development of the power industry, the discharge of fly ash from coal-fired power plants has increased year by year. According to statistics, my country's fly ash emissions in 2015 reached 620 million tons. Although the utilization rate of fly ash in our country is as high as 70%, there are still a large amount of fly ash stockpiled, which has caused serious environmental pollution problems. At present, fly ash is mainly used as raw materials for bulk building materials such as cement, admixtures for mine backfill, additives for plastics and rubber, etc. Its consumption is almost entirely dependent on traditional methods, and there are problems of low ...

AI Technical Summary

Problems solved by technology

Many researchers have actively explored the preparation of silicon carbide fibers by carbothermal reduction reaction, and achieved many original research results, but there are still many problems to be solved, such as the high cost of raw materials and the low reactivity of raw materials. The reaction temperature is high and the reaction time is long, the product part has a non-fibrous shape, and the mechanical properties of the product are reduced due to poor crystal form, etc.

Images