Method for directly preparing high-purity silicon and titanium-silicon alloy from titanium-silicon materials

Abstract

The invention relates to a method for directly preparing high-purity silicon and titanium-silicon alloy from titanium-silicon materials, and belongs to the technical field of efficient and comprehensive utilization of titanium-silicon material resources. Titanium-silicon materials with different contents of silicon are adopted as raw materials, electromagnetic induction is adopted for heating andmelting, and vacuum volatilization is conducted on the molten alloy materials under air pressure for refining and impurity removal; electromagnetic stirring is conducted on the molten materials obtained after the impurity removal for directional solidification and strengthened separation, and during the directional solidification, silicon which is preferentially precipitated deposits on the bottomof a crucible under the action of an electromagnetic stirring force and a temperature gradient; however, a titanium-silicon alloy phase is precipitated on the upper part of the crucible, and two products, the high-purity silicon and the titanium-silicon alloy, are obtained; the products is cut along an interface of separation, and the high-purity silicon with low contents of boron and phosphorusand the titanium-silicon alloy with low content of iron are obtained. According to the method for directly preparing the high-purity silicon and the titanium-silicon alloy from the titanium-silicon materials, the purity of the obtained high-purity silicon is more than 99.995%, and the content of titanium in the titanium-silicon alloy is 20-30%; compared with a traditional preparation technology of the high-purity silicon and the titanium-silicon alloy, the method has the advantages of being short in process, low in cost and the like, and mass production is easy to achieve.

Description

technical field [0001] The invention relates to a method for directly preparing high-purity silicon and titanium-silicon alloys from titanium-silicon materials, and belongs to the technical field of comprehensive utilization of high-efficiency resources of titanium-silicon materials. technical background [0002] As a renewable, non-polluting, and inexhaustible new energy source, solar photovoltaic power generation has become an important development direction for commercial development and utilization in countries all over the world. The optoelectronic devices in solar photovoltaic technology are all made of crystalline silicon with a purity requirement of 99.9999% (6N). At present, the production cost of solar grade silicon at home and abroad is relatively high, the relative energy consumption is large, the process route is long, and the pollution is large. Therefore, how to prepare solar-grade polysilicon at low cost and more economically and environmentally friendly is a...

AI Technical Summary

Problems solved by technology

However, titanium and titanium alloys have high chemical activity, and are easy to react with various gases and refractory materials during smelting; at the same time, the obtained alloys are prone to macroscopic and microscopic segregation, poor chemical composition uniformity, and structural defects; therefore, it is necessary to seek a way to prepare high-quality titanium alloys The process is very urgent

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