Fluorocarbons

bolbuyk · 2004-04-08 12:04:11

I read in any comment on this forum about production of fluorocarbons to make a greenhouse-effect. Somebody said it would ask millions of tons. Is this much? I don't think so. When you make, say, ten factory's that produce 10 million kg a year, which are rather big factory's but not extremely, it must be possible to put enough in the martian atmosphere in some decades.

I think the most important question is the availability in the martian ores. Maybe the fluorocarbons can directly synthesized from a proces with certain conditions (pressure and temperature with a catalyst) so that CO2 reacts with MFx to CF4 and MOy, where M is some metal.

Antoher question is then the energy that is required, meaybe fusion?

And also a question: Do we want to put this toxic stuff in the martian atmosphere? :bars:

SBird · 2004-04-08 12:14:40

Fluorocarbon compounds, when properly designed are remarkably non-toxic. However, the UV breakdown products could be an issue. The biggest issue will be where to get the flourine. If there are ample natural flourine containing ores, that's fine but having to import millions of tons of anything from Earth is going to be an economic no-go.

kippy · 2004-04-08 12:22:24

I wasn't aware that PFCs and CFCs were toxic. In fact, I'm pretty sure you can breath them just fine provided you have enough O2. Someone can correct me if I'm wrong.

Since powering greenhouse factories isn't going to be as immediately important as heating and powering settlements, they would probably use whatever power was used normally. That's probably going to be fission. Perhaps fusion when it comes of age. Maybe solar or wind if they want to be really passive about it.

I'm unsure about the amounts but what I'm really curious about is the mixture. The closest thing I could find was [http://www.users.globalnet.co.uk/~mfogg/marsfront.html]here. It looks pretty incomplete but promising. It points out that a mixture of greenhouse gasses will be needed to get an optimal greenhouse effect. Both different types and different concentrations will be needed. This seems like a good project to follow up on. Perhaps a terraforming research project for the Mars Society could be formed.

bolbuyk · 2004-04-08 15:10:43

CF4 non-toxic? That's nice!

BTW I hope Nuclear fusion will be availeble before terraforming of Mars is going to start.

kippy · 2004-04-08 15:49:20

CF4 non-toxic? That's nice!

According to [http://ptcl.chem.ox.ac.uk/MSDS/CA/carbo … oride.html]this CF4 is "Asphyxiant at high concentrations." That goes for a lot of gasses including CO2. It's doubtful that the concentration of CF4 would every be as high as CO2 and we breathe just fine right now.

SBird · 2004-04-08 16:18:29

CF4 is almost completely inert. It has been shown, though, that some flourine compounds can be highly toxic. It turns out that the telfon in non-stick frying pans isn't such a good idea - at high temperatures, organic molecules in food can react with flourine. It turns out that birds are much more sensitive to these compounds and can die if the owner uses non-stick cookware a lot. I have concerns about free flourine being released by UV intereaction and creating potentially toxic compounds.

SBird · 2004-04-08 16:22:44

Pretty much everything except O2 is an asphyxiant. Plain 'ol N2 will kill you plenty fast if you take a few lungsfull of it.

RickSmith · 2007-03-11 02:49:30

Hi everyone,
Fluorine atoms are extreamly powerful oxidizers. In fact they are better oxiders than oxygen is. (If you start out with an atmosphere of fluorine and silicon - oxygen rocks you would end up with an oxygen atmosphere and silicon - fluorine rocks.)

The point of the chlorofluorocarbons and the perfluorocarbons is that the fluorine binds so tightly to the other atoms that very few chemical reactions at standard temperatures and pressures are capable of breaking them away. This makes the compounds extremely non-reactive.

You could break up these molecules with a lot of heat energy. Or if you have exactly the right frequency of high energy ultraviolet light that can do it.

These compounds are very safe for humans. In fact, they inflate eye balls with them for some operations and let the blood stream pull the gas out as the eye refills with jelly. The gas is exhaled from the lungs into the atmosphere. See this post by RobertDyck:

PFC Are Non-Toxic

In any case, the point is perfluorocarbons are amoung the least toxic of any substances on the planet. Having them in parts per million concentration would have no effect on people, except to make the planet warmer of course.

Warm regards, Rick

karov · 2007-03-14 08:28:30

Isn`t it Silicon-fluoride a gas?

RickSmith · 2007-03-14 19:22:42

Hi Karov,
I looked up SiF4 and you are right, it is a gas. Wow! I'm impressed that you know that off the top of your head. The line about silicon oxide rocks --> silicon fluoride rocks was cribbed from "World Building" by Stephen L. Gillett and was mainly given as an example of how oxidizing fluorine is.

I bow to your chemisty geeki-ness!

Warm regards, Rick.

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#1 2004-04-08 12:04:11

Re: Fluorocarbons

#2 2004-04-08 12:14:40

Re: Fluorocarbons

#3 2004-04-08 12:22:24

Re: Fluorocarbons

#4 2004-04-08 15:10:43

Re: Fluorocarbons

#5 2004-04-08 15:49:20

Re: Fluorocarbons

#6 2004-04-08 16:18:29

Re: Fluorocarbons

#7 2004-04-08 16:22:44

Re: Fluorocarbons

#8 2007-03-11 02:49:30

Re: Fluorocarbons

#9 2007-03-14 08:28:30

Re: Fluorocarbons

#10 2007-03-14 19:22:42

Re: Fluorocarbons

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