Sciencemadness Discussion Board

3M HCl solution in Ethyl Acetate

002oo - 26-11-2018 at 10:57

So I was recently attempting to gas Ethyl acetate with HCl gas to make a 3M HCl solution in Ethyl Acetate.

To achieve this I took 1L of Ethyl Acetate and planned to gas with HCl till a gain of ~110g was achieved, which would give me a 3M HCl solution in 1L of Ethyl Acetate.

All was going very well(couldn't even smell the HCl gas one bit) until around ~50g of HCl gas absorbed into the 1L of Ethyl Acetate. Then it seemed the Ethyl Acetate was fully saturated and the HCl gas just bubbled through it and escaped, even after stopping the HCl gassing, HCl gas continued to fume off of the Ethyl Acetate.

What could be the problem?

Sigmatropic - 26-11-2018 at 11:09

I seemed to recall that there was 4M HCl in ethyl acetate (commercially available) but on searching I could only find 1M HCl in ethyl acetate being available.
The problem could be the temperature, HCl dissolution is exothermic although I don't know exactly how exothermic and at higher temperatures the solubility of gasses in solvents goes down. Perhaps chil the ethyl acetate then saturate and allow to warm to RT, but be aware of the HCl that will offgas during the warming.

002oo - 26-11-2018 at 12:01

Quote: Originally posted by Sigmatropic  
I seemed to recall that there was 4M HCl in ethyl acetate (commercially available) but on searching I could only find 1M HCl in ethyl acetate being available.
The problem could be the temperature, HCl dissolution is exothermic although I don't know exactly how exothermic and at higher temperatures the solubility of gasses in solvents goes down. Perhaps chil the ethyl acetate then saturate and allow to warm to RT, but be aware of the HCl that will offgas during the warming.


The Ethyl Acetate was already in a ice bath during the process.

Would water in the Ethyl Acetate lower the solubility for the HCl gas? It was high purity but only technical grade Ethyl Acetate, and since it was just something ive been wanting to try for fun I didn't bother to dry the Ethyl Acetate prior.

What issues could render the Ethyl Acetate from absorbing more HCl gas?

Sigmatropic - 28-11-2018 at 22:44

Did you stir the Ethyl Acetate?