Unlock instant, AI-driven research and patent intelligence for your innovation.

Gas phase chlorination method of dichlorosilane

A technology of dichlorodihydrosilane and hydrogen, which is applied in the direction of silicon halide compounds, halosilanes, etc., can solve problems such as difficult to control and full of explosions, and achieve the effect of avoiding explosive reactions

Active Publication Date: 2015-02-18
宁夏胜蓝化工环保科技有限公司
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The existing research and production practice on dichlorodihydrosilane shows that the mixed gas formed by dichlorodihydrosilane and oxidant such as air, oxygen, chlorine, etc. has a very wide explosion limit, and the flash point of dichlorodihydrosilane is -37°C, and because reaction (1) is a strong exothermic reaction, the reaction of using chlorine to chlorinate gaseous or liquid dichlorodihydrosilane into silicon tetrachloride becomes uncontrollable and full of danger of explosion, which is The reason why there is no report on the use of chlorine to chlorinate dichlorodihydrosilane to prepare silicon tetrachloride

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0015] Hydrogen with purity of 99.9% and chlorine with purity of 99.6% enter the burner through their respective pipes. The flow of chlorine is 1 kmol / h, the flow of hydrogen is 1.05 kmol / h, and the excess hydrogen is 5%. When hydrogen and chlorine form a stable combustion flame Then, slowly inject dichlorodihydrosilane gas into the hydrogen stream (the molar content of nitrogen in dichlorodihydrosilicon is 0%, and the molar content of hydrogen chloride is 0.1%), while reducing the molar flow of hydrogen proportionally. When the silicon flow rate reaches 0.05 kmol / h and the hydrogen flow rate is 0.95 kmol / h, the respective flow rates are maintained to make the combustion reaction proceed stably. After 1h, the reaction products were analyzed by gas chromatography (the gas chromatography uses helium as the carrier gas and TCD as the detector). The analysis results were 2.5% for silicon tetrachloride, 95% for hydrogen chloride, and 2.5% for hydrogen. No dichloride was detected. Hy...

Embodiment 2

[0017] Hydrogen with purity of 99.9% and chlorine with purity of 99.6% enter the burner through their respective pipes. The flow of chlorine is 1 kmol / h, the flow of hydrogen is 1.05 kmol / h, and the excess hydrogen is 5%. When hydrogen and chlorine form a stable combustion flame Then, slowly inject dichlorodihydrosilicon gas into the hydrogen stream (the molar content of nitrogen in dichlorodihydrosilicon is 0%, and the molar content of hydrogen chloride is 0.1%), while reducing the molar flow of hydrogen proportionally. When the silicon flow rate reaches 0.45 kmol / h and the hydrogen flow rate is 0.15 kmol / h, the respective flow rates are maintained to make the combustion reaction proceed stably. After 1h, the reaction products were analyzed by gas chromatography (gas chromatography using helium as the carrier gas and TCD as the detector). The results of the analysis were 28.1% of silicon tetrachloride, 68.8% of hydrogen chloride, and 3.1% of hydrogen. No dichloride was detected...

Embodiment 3

[0019] The hydrogen with purity of 99.9% and chlorine with purity of 99.6% enter the burner through their respective pipes. The flow of chlorine is 1 kmol / h, the flow of hydrogen is 1.1 kmol / h, and the hydrogen excess is 10%. When hydrogen and chlorine form a stable combustion flame Then, slowly inject dichlorodihydrosilane gas into the hydrogen stream (the molar content of nitrogen in dichlorodihydrosilicon is 0%, and the molar content of hydrogen chloride is 0.1%), while reducing the molar flow of hydrogen proportionally. When the silicon flow rate reaches 0.5 kmol / h and the hydrogen flow rate is 0.1 kmol / h, the respective flow rates are maintained to make the combustion reaction proceed stably. After 1h, the reaction products were analyzed by gas chromatography (the gas chromatography uses helium as the carrier gas and TCD as the detector). The analysis results were 31.2% silicon tetrachloride, 62.5% hydrogen chloride, and 6.3% hydrogen. No dichloride was detected. Hydrogen ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides a method for chlorinating dichlorosilane, a byproduct of polysilicon, in a gas phase. The method is characterized by utilizing flames generated by stable combustions of hydrogen and chlorine as initial reaction space, pumping dichlorosilane into hydrogen stream or directly pumping dichlorosilane to the bottoms of hydrogen and chlorine flames, simultaneously reducing hydrogen flow in proportion, triggering dichlorosilane and chlorine to carry out stable gas phase combustion reaction by the hydrogen and chlorine flames and chlorinating dichlorosilane to silicon tetrachloride. For polysilicon factories, transforming dichlorosilane to silicon tetrachloride is one of the best ways to achieve dichlorosilane recycling.

Description

Technical field [0001] The invention relates to a method for chlorination of dichlorodihydrosilicon in the gas phase, and more specifically, to a method for preparing silicon tetrachloride by burning and chlorinating the by-products of polysilicon dichlorodihydrogen and chlorine in the gas phase. Background technique [0002] Dichlorodihydrosilane is an important by-product other than silicon tetrachloride in the modified Siemens process of polysilicon production. Some polysilicon manufacturers mix it with trichlorosilane in a certain proportion and send it to the reduction furnace for polysilicon growth, such as China Patent CN102642834A. However, production practice shows that sending too much dichlorodihydrosilane into the reduction furnace will cause a series of problems such as inconsistent deposition of silicon rods and clogging of pipelines with silicon powder. Therefore, the method of using dichlorodihydrosilicon in a certain proportion for polysilicon deposition is subj...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C01B33/107
Inventor 沈俊赵燕
Owner 宁夏胜蓝化工环保科技有限公司