Highly concentrated formic acid slowly decomposes into carbon monoxide and water. The formation of gas increases the pressure in the bottle, which can cause it to explode. The decomposition reaction accelerates at temperatures as low as 30 °C.

Thank you Michel for your useful answer. How can we prevent this event to happen in the future? What are the measures you recommend to prevent this risk? My second question is what we have to do after this explosion? How can we clean the place of explosion?

Many thanks

Duried

I think we must share this information with everyone who works with this acid!!! it is a very dangerous chemical!!!!

Maybe a fermentation lock (Gärspund) can help.

Regards,

Joachim

Can you Dear Joachim give us more information or reference about your suggestion please?

Dear Duried,

if you brew something, aside from alcohol CO2 is produced which would damage the barrel. To avoid this, a fermentation lock lets gases escape, and normally no gases are sucked in back. Water or alcohol prevent convection, that means mixing surrounding air with gases inside the barrel. Also, vinegar and other bacteria are kept out this way.

https://www.youtube.com/watch?v=L797ewwtSVU

https://www.google.com/search?q=gärspund&source=lnms&tbm=isch

Regards,

Joachim

Joachim Pimiskern and Michel Héry , Thank you very much for your useful answers.

Regards

Duried

Hello.

I am not a specialist in these matters, but I am happy to share my knowledge of the subject. I think that to avoid these explosions, it is necessary to ensure that the formic acid is not exposed to a temperature higher than 25 or 30°C, which could trigger the reaction that will gradually increase the gas pressure, with the risk of an explosion in the end. It is advisable to protect the containers with a properly fitting outer casing, e.g. made of high density polyethylene.

To decontaminate surfaces, I can tell you about my experience with several litres of sulphuric acid contained in a bottle that had broken. Our technicians were equipped with boots, disposable overalls, safety glasses and acid-proof gloves and they recovered as much sulphuric acid as possible with absorbent paper thrown into a plastic bin. We finished by rinsing with slightly basic water.

https://www.inrs.fr/publications/bdd/fichetox/fiche.html?refINRS=FICHETOX_149

Michel Héry, thank you very much for sharing your experience and the link.

Regards

Duried

https://www.nj.gov/health/eoh/rtkweb/documents/fs/0948.pdf