Is this fictional planet possible?

Question

I was trying to make an interesting moon of a gas giant similar to Jupiter with a liquid ocean of water. The moon orbits in the equivalent orbital space of Io and is about twice the size of Mars. This moon is kept warm by greenhouse gases in the atmosphere and tidal heating. The moon's atmosphere has a trace amount of Sulfur Hexafluoride, which is a greenhouse gas much stronger than CO2.

This gas is produced by the large amount of volcanoes on the moon, which also produce other chemicals such as Fluoride Acids and Sulfuric Acid, which makes the planet's atmosphere and oceans very acidic. The ocean has an average pH of 3. It is also very salty, which keeps it liquid even though the average temperature of the moon is -15 degrees Celsius. My goal for this moon was an ocean planet with a toxic atmosphere located in orbit of Jupiter. Is this planet realistically possible in real life?

Answer 1

Back in the times when I worked with a linear accelerator using Sulfur Hexafluoride as isolating gas, I was told that the "no smoking" alert allround the accelerator was due to the fact that Sulfur Hexafluoride was not toxic but had the ability to react with water at high temperatures and decompose in fluoridic acid and sulphuric acid. So if you happen to smoke while in the room there was a leak of Sulfur Hexafluoride you would have given a thourough cleaning to your lungs.

Now your planet has something similar: Sulfur Hexafluoride, Water and high temperatures during volcanic eruptions. While this can account for the presence of those acids in the enviroment, it can make more difficult to build up a significative amount of Sulfur Hexafluoride in the atmosphere.

So I guess it all depends on how much Sulfur Hexafluoride you want to have in the atmosphere.