What are the requirements for hydrogen chloride gas in the production of trichlorosilane?
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What are the specific requirements for hydrogen chloride gas in the production of trichlorosilane? As far as I know, most of them are synthesized using chlorine and hydrogen, and only their control indicators are mentioned. What if I want to use hydrogen chloride gas directly? Does it also have to be above 99%? If we want to produce 99% hydrogen chloride, what kind of chlorine and hydrogen are needed?
Ordinary liquid chlorine gasification chlorine is enough, and hydrogen is dehydrated by freeze-drying, because hydrogen chloride synthesis and subsequent equipment are basically made of carbon steel.
As far as I know: Direct use of hydrogen chloride requires more than four nines, and the current domestic caustic soda process does not seem to be able to provide it. If chlorine and hydrogen are used, the requirements are as follows: 1． Chlorine gas liquid chlorine specifications: Meet the chlorine content required by the national standard for premium products: 99.8% (v/) water content: 0.015% (wt) pressure: 0.7MPAG temperature: Greater than saturation temperature 2. H2 purity≥99.97%(v) N2＜200 ppmv O2＜5 ppmv H2O＜1 ppmv CO/CO2＜10 ppmv Pressure: 1.0MPAG temperature: normal temperature
Can the hydrogen chloride produced by desorbing hydrochloric acid be used directly?
The specific requirements for hydrogen chloride gas in the production of trichlorosilane are mainly water content, which affects the yield. We generally require less than three thousandths. The chlorine and hydrogen contents are less important. When hydrogen chloride is synthesized, hydrogen is present in excess.
For the production of trichlorine, HCL produced by a chlor-alkali plant can be used directly. Generally, 93 to 97 can meet the requirements. However, of course, the higher the purity, the better. It is good for reducing compression power consumption and improving conversion rate. Too high water content will have a negative impact on production.
The key is to control the moisture. Excess internal and external H2 is sufficient. The higher the content, the better. Our crude product is generally around 87
The requirements for hydrogen chloride are not that high. It only needs to be between 94-96.5. The higher the purity, the easier it is to react. The requirements for chlorine and hydrogen are mainly to prevent it from containing water, otherwise the silicon powder will harden the material.
The control of hydrogen chloride mainly depends on the water content in hydrogen chloride. Our current requirement is that the water content of hydrogen chloride is below 100PPM. The control of chlorine and hydrogen is not very strict, but it is necessary to control the water content.
My company’s requirements for hydrogen chloride in the synthesis of trichlorosilane: If it is hydrogen chloride HCL>=96% H2 synthesized by chlorine and hydrogen
The key is to control moisture, ensure excess H2, and use bag dust removal well!
Yes, control the water content, otherwise it will cause slagging and blockage in the subsequent system, affect the synthesis purity, and have a greater impact on the equipment. After all, hydrogen chloride gas corrodes pipelines and affects product quality. hydrogen: Chlorine is generally controlled at 1.1: Around 1 to 0.9, ensuring excess hydrogen
Mainly to control the water content. Reason 1. Hydrochloric acid corrodes metal pipes.； 2. Water will react with the product SiHCL3 to generate SiO2, which will reduce the yield and may block the pipeline.
Our company's trichlorosilane requires more than 90% of hydrogen to be used. This is what the technology provider says. Said to be beneficial for reactions. If synthetic hydrogen chloride is used, the excess amount of hydrogen can be controlled to a high point during synthesis, which is very convenient. If the by-product hydrogen chloride is used, a certain amount of hydrogen must be prepared. This is also very convenient. After adding the silicon powder, use a hydrogen pipe to purge it clean. . The by-product hydrogen chloride used by our company was later switched to nitrogen for safety reasons.
Can hydrogen chloride, a by-product of benzyl chloride, be used in the production of trichlorosilane? The by-product hydrogen chloride may contain trace amounts of toluene and benzyl chloride