I was thinking to react Cl2 + 2HF -> F2 + 2HCl
This doesn't work. Fluorine is a much stronger oxidiser than chlorine. It will work in the opposite direction, though.
Here's three reactions that might help:
SO2 + KF --> KSO2F
KSO2F + Cl2 --> SO2ClF + KCl
SO2ClF + KSO2F --> SO2F2 + KCl + SO2 (@180 celsius)
SO2 and SO2F2 are both gases. However, SO2 condenses at about -10 celsius, while SO2F2 condenses around -55 celsius
I bring this topic to the surface again, i wanna give improvement based on your thoughts and helps.
So, i tried the reactions above ( thanks "lost and found" ! ). I synthesize chlorine from Ca(OCl)2 + HCl ( also from this forum ) and SO2 from sodium sulfite+HCl. But, since I didn't have KF, I substituted it with BaF2.
I did the reactions, and I got colorless gas which I put in ampoule. I haven't tried to check it by condensing it. I tested the gas to cockroach. I injected 2 mL to the jar filled with a cockroach, and it's dead. So, until now, I concluded that the gas is very poisonous, and I believe the gas contains SO2F2 ( the gas I tried to make ) in small amount.
That's the improvement until the day before X'mas.
After X'mas and New Year break, I'll try to :
1. Test the gas composition with GC.
2. Conduct the same reaction with longer reaction time and more precise amount of the reactant in order to get higher purity of SO2F2.
3. Conduct the reaction with KF ( I'm waiting for the KF I ordered. )
That's the follow up of our discussions, guys. Thanks anyway and I'll be waiting for critics and suggestions.