Catalyst used for preparing trichlorosilane through silicon tetrachloride cold hydrogenation, and preparation method thereof

Abstract

The invention discloses a catalyst used for preparing trichlorosilane through silicon tetrachloride cold hydrogenation, and a preparation method thereof. The catalyst is copper-nickel alloy with a nickel mass content of 10-35%. According to the catalyst provided by the embodiment of the invention for preparing trichlorosilane through silicon tetrachloride cold hydrogenation, the catalyst has high excellent high-temperature stability, and is prevented from a bonding phenomenon under high-temperature calcining in the reaction process. Also, high-temperature pre-activation is not needed before the reaction. After the reaction, no oxidation reaction is needed upon the catalyst and the reaction residue. The residue can be directly discharged, and no pollution to the environment is caused.

Description

technical field [0001] The invention relates to the technical field of polysilicon production technology, more specifically, the invention relates to a catalyst for preparing trichlorosilane by cold hydrogenation of silicon tetrachloride and a preparation method thereof. Background technique [0002] At present, most manufacturers use the trichlorosilane reduction process to produce polysilicon. In this production process, nearly 20 tons of silicon tetrachloride is produced as a by-product for every ton of polysilicon produced. A 2,000-ton polysilicon factory produces more than 40,000 tons of tetrachloride per year. Silicon chloride. Silicon tetrachloride is liquid at room temperature, so it is not suitable for storage and transportation. At the same time, the market capacity of silicon tetrachloride is limited, which has resulted in the difficult situation of silicon tetrachloride treatment. With the expansion of the scale of polysilicon industrialization, the processing ...

AI Technical Summary

Problems solved by technology

[0004] 1. The price is high, generally as high as 300,000 to 350,000 yuan / t

Higher cost of trichlorosilane leading to cold hydrogenation conversion of silicon tetrachloride;

[0005] 2. The carrier of the nickel-based catalyst is alumina, which will cause high aluminum content in the trichlorosilane converted by the cold hydrogenation of silicon tetrachloride, which will eventually affect the quality of polysilicon products;

[0006] 3. Before using nickel-based catalysts, high-temperature activation is required, which consumes a lot of energy and also results in high production costs;

[0007] 4. The finished nickel-based catalyst is difficult to handle and needs to be oxidized. The oxidation process is highly exothermic and dangerous

At the same time, spent nickel-based catalysts are hazardous wastes that require strict recycling

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