Flotation agent for purifying silicon carbide in mortar and preparation method thereof

Abstract

A flotation agent for purifying silicon carbides from mortar is composed of, by weight, 3-5 parts of oxidized paraffin, 20-24 parts of n-butyl alcohol, 6-8 parts of oleic acid, 2-3 parts of ricinoleic acid, 4-7 parts of sodium hexametaphosphate, 50-55 parts of methyl alcohol, 30-35 parts of diesel, 4-5 parts of assistants and 40-50 parts of water. According to the flotation agent, multiple sorts of solvents and water are used, under the action of a surface active agent, a stable emulsification system is formed, the interfacial tension of silicon and the silicon carbides is changed, and the silicon and the silicon carbides are separated. According to the floating agent, the silicon and the silicon carbides are separated more completely, the purity of the obtained silicon carbide powder is higher, a high-speed centrifugation mode is avoided, and the economic benefits are improved.

Description

technical field [0001] The invention relates to the technical field of powder separation of silicon and silicon carbide in mortar produced by a silicon wafer wire sawing process, in particular to a flotation agent for purifying silicon carbide in mortar and a preparation method thereof. Background technique [0002] Various silicon wafers, including monocrystalline silicon and polycrystalline silicon solar cells, and silicon wafers for the microelectronics industry, are generally produced by cutting with wire saws and silicon carbide abrasive slurry, referred to as mortar. The thickness of the silicon wafer is generally 0.22mm, and there is no development trend of thinning at present. The width of the wire saw kerf is generally 0.18-0.30mm, which means that 20-60% of the high-purity silicon material will enter the mortar as sawdust, and its extraction Recycling is equivalent to opening up a new and sizable source of high-purity silicon raw materials. [0003] Although the b...

AI Technical Summary

Problems solved by technology

[0003] Although the benefits of recovering high-purity silicon are considerable, the physical and chemical properties of silicon and silicon carbide are relatively close. So far, there are few research results on this project, and there are no successful cases of actual production. Further research is needed on feasible methods for actual production. Separation agents and methods