The issue of trichlorosilane leakage
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When TCS leaks, colored smoke can be seen; the reason for this is SiHCl3 + 1/2O2 + H2O → SiO2 + 3HCl↑. Could someone please tell me what color that smoke is? Also, what is the substance formed when TCS reacts with water, namely (HSIO)2O? Is it a polycondensation product of silicic acid? Thank you
If there is a very small leak of trichlorosilane in the equipment pipes, white substances—silicon dioxide crystals—can generally be seen on those pipes. If the leakage is high, white smoke will definitely appear – it’s obvious! :lol
If the quantity is large, cut off the upstream source and pay attention to the wind direction
When first encountering the trichlorosilane method, I mistakenly believed that a leak of trichlorosilane would produce phosgene, which worried me for a long time. When trichlorosilane comes into contact with moisture, it easily decomposes to release HCl, producing white smoke; the resulting SiO2 tends to accumulate at the leak site, making the white substance easy to spot. When performing repairs, pay attention to the wind direction and try to avoid coming into contact with trichlorosilane.
A leak of trichlorosilane produces white smoke; in the event of a large-scale leak, thick clouds of smoke are generated and spread downward. It becomes particularly dangerous when there is rain or wind, as the smoke is extremely irritating to breathe. After hydrolysis, SO2 is the main substance produced, and it is this SO2 that is used to manufacture silica gel through the SCI4 process
With minor leaks, white mist and white substances can be seen. White mist: Small water droplets formed when HCl comes into contact with moisture in the air. White solid: SiO2. In large quantities: a colorless liquid and smoke can be seen.
I would like to remind the original poster that if the amount of leakage is small, the white lumps formed (containing hydrogen and silicon trichloride vapor) can be explosive; please be careful.
You can see it; the white solid that forms at the leakage site is visible with just a little closer inspection
If it leaks, everything will turn white; it’s the substance produced when trichlorosilane reacts with water in an oxygen-free environment – it’s probably something similar to silicic anhydride
A white substance is formed; if the amount of leakage is large, it may catch fire or even explode