Sciencemadness Discussion Board

Novel way to produce HF-NaF?

Germanys_Finest - 16-11-2006 at 18:44

I have a can of dust-off (difluoroethane) and the decompostion product is HF. I will be setting up a boiling flask with 1 hole rubber stopper with tubing leading into an erlenmeyer flask with dh2o and strong magnetic stirring to capture the HF vapors.

The question is at what temp. does difluoroethane decompose?

Really my purpose is to produce NaF so should I just bubble this HF gas through a NaOH sol. or produce aq. HF first then react the 2 compounds?

Thanks in advance!

Jdurg - 16-11-2006 at 19:02

Bubble through a concentrated NaOH solution. HF eats glass like it's candy. By bubbling HF into your erlenmeyer flask, you will destroy your flask. There is no doubt about that. You would be best off doing this in a plastic container. In addition, make sure that you have plenty of calcium gluconate gel around in case you get any HF on your skin. It's fairly nasty if you're not careful with what you are doing.

Twospoons - 16-11-2006 at 19:02

Well, it definitely decomposes on ignition! My workmate and I used to send fireballs at each other using freeze spray cans - until, after choking on the fumes, I read the can and realised we were lighting an HFC - and the choking gas probably contained HF :o

unionised - 18-11-2006 at 10:04

I think you might do better passing the gas over hot NaOH or Na2CO3. That way you don't have to deal with HF.

Chris The Great - 18-11-2006 at 18:03

Would the gas react directly with NaOH to give NaF and various unwanted organic compounds? If so that would be the easiest method, just spray the gas into a hot solution of NaOH or solid NaOH if that is needed.