3 ms·

"haha, only serious" question: Can we use something like CFCs to break down the ozone?

kragen 3y ago
it's not the cfcs themselves but their chlorine breakdown product (in uv light). certainly there are disadvantages to adding free halogens such as fluorine and chlorine to your air (chlorine used to be a major chemical warfare agent, and fluorine wasn't only because there's no practical way to carry it around, it being the closest real equivalent to the legendary alkahest), but unlike cfcs halogens are not persistent in the environment, and it's not unimaginable that the required levels of halogens would be less harmful than the ozone they removed platinum, though, can catalyze the same decomposition that chlorine does, so i suspect that a much more reasonable approach is to use platinum catalytic converters, so the catalyst remains contained with a box instead of going into your lungs
tempestn 3y ago
Ha, I love it. I imagine spraying those into the rooms would be even worse though. And if you do it in an HVAC system you might as well just do the UV there too, in which case the ozone would break down before it was an issue. (And in fact could even be beneficial killing pathogens itself.) The main advantage of the near UV lights is that they can be inexpensively placed in locations that don't have good HVAC systems.
kadoban 3y ago
Doesn't sound likely to me. I looked it up and what happens is that over long time periods in sunlight, CFCs lose a chlorine radical, and that chlorine radical lives for a long time and catalyzes ozone to turn into normal oxygen molecules. So it would only even possibly be effective if you have so much CFCs and so much light that it builds up a bunch of chlorine, enough to get rid of all of the ozone. My guess is that even if those reactions occur in the context of a home (which seems like a big if) they'd be so slow and require so much chlorine and CFCs around that you'd be dead before you could celebrate. Not to mention you'd have to be releasing CFCs in ~every building constantly, which would destroy the ozone layer orders of magnitude worse than we did decades ago.

it's not the cfcs themselves but their chlorine breakdown product (in uv light). certainly there are disadvantages to adding free halogens such as fluorine and chlorine to your air (chlorine used to be a major chemical warfare agent, and fluorine wasn't only because there's no practical way to carry it around, it being the closest real equivalent to the legendary alkahest), but unlike cfcs halogens are not persistent in the environment, and it's not unimaginable that the required levels of halogens would be less harmful than the ozone they removed platinum, though, can catalyze the same decomposition that chlorine does, so i suspect that a much more reasonable approach is to use platinum catalytic converters, so the catalyst remains contained with a box instead of going into your lungs

tempestn 3y ago

Ha, I love it. I imagine spraying those into the rooms would be even worse though. And if you do it in an HVAC system you might as well just do the UV there too, in which case the ozone would break down before it was an issue. (And in fact could even be beneficial killing pathogens itself.) The main advantage of the near UV lights is that they can be inexpensively placed in locations that don't have good HVAC systems.

kadoban 3y ago

Doesn't sound likely to me. I looked it up and what happens is that over long time periods in sunlight, CFCs lose a chlorine radical, and that chlorine radical lives for a long time and catalyzes ozone to turn into normal oxygen molecules. So it would only even possibly be effective if you have so much CFCs and so much light that it builds up a bunch of chlorine, enough to get rid of all of the ozone. My guess is that even if those reactions occur in the context of a home (which seems like a big if) they'd be so slow and require so much chlorine and CFCs around that you'd be dead before you could celebrate. Not to mention you'd have to be releasing CFCs in ~every building constantly, which would destroy the ozone layer orders of magnitude worse than we did decades ago.