[TuDzi]

Does anyone know of a safe method for disposing of silicon tetrachloride or at least inactivating residues left over in glassware?  

I would prefer to hydrolyze it to silica, but hydrolysis is very exothermic and yields HCl.  One idea is to use a pyridine/H₂O wash.  Any advice would be helpful!  Thanks.

[TuDzi]

Well, here's what I did, in case anyone's interested:

I added isopropyl alcohol dropwise to the SiCl4.  This was still pretty exothermic, but reacted slower so that HCl vapor production was reduced.  After the SiCl4 was quenched, I simply diluted with aqueous NaOH to neutralize the HCl.

This was the first time that I worked with SiCl4 and was a little nervous about it.  I've read that mixing with water can be explosive and it was the HCl vapor evolution that worried me a bit.  It wasn't so bad to work with, but safety precautions must be taken with this chemical!

[Donaldson Tan]

 

[rudolph661]

We run it though a V-Type plasma to produce fumes silica and chlorine gas. We neutralize the chlorine in a duel step scrubber system containing HF to prevent gel formation and KOH to react with the chlorine. the fumes silica is filtered out of the off gas stream and sold as a product. please contact me if you need additional information.