The question is how much CO2 can I fix with a reasonably sized apparatus and really I would prefer a continuous system (which is why electrolysis) rather than a batch system.

Also I would prefer levels lower than outside, obviously air exchangers will necessarily be worse than just being outside.

You might try using oxygen conentrator with high throughput to concentrate oxygen from outside and pump it into your home.

With small device I could drop CO2 levels to zero in volume of a gargabe bag in few minutes.

But that would give you oxygen rich atmosphere. You'd probably want to add some inert gas to that. Nitrogen preferably. Are there nitrogen concentrators?

Also all of that is probably really dangerous because human body doesn't detect oxygen level, just CO2 level. So you might easily pass out and suffocate without any warning if your oxygen supply unit get damaged but your nitrogen supply unit doesn't.

We are still talking about home... on planet Earth, right?

Of course. :-) The whole idea is based onthat ouside of the fact that there's plenty of oxygen for the concentrator to concentrate.

I'd assume that some chemist or other has already published a paper about that. But you could probably figure it out yourself experimentally by weighing quicklime, letting it react and weighing it again. Start a youtube channel to finance the project :)

Well I've gotten as far as purchasing 20 pounds of baking soda... my experiments thus far haven't been able to remove a detectable amount of CO2 from a room.

My literature searches haven't had much success thus far, lacking a chemistry degree hasn't helped. I have found some things but not enough to come to any sort of engineering designs. I'm assuming it's one of those things that's almost too simple for anyone to have bothered writing a paper about unless they had the exact sort of ideas I did. (OR they're using terms that I haven't been able to come up with yet)

Try buying 20 lbs of calcium hydroxide, it is sometimes used for soap making iirc, so it should be available on amazon. Bubbling air through a concentrated solution should do something. At least at the CO2 concentrations of exhaled air you get visible amounts of insoluble carbonate: https://www.youtube.com/watch?v=Vl9A8Iyc_LY

Really prefer co2 levels lower than outside? What's your outside environment?

Before the industrial revolution the CO2 levels outside were around 250ppm or at least less than 300.

Current levels outside as measured by my device just now are about 450ppm.

Here is a nice historical chart: https://www.climate.gov/sites/default/files/CO2_emissions_vs...

My measurement is also about 450ppm and it's fine for me. How do you discovered lower level is better for you?

I don't know for sure, but there are certain things I notice which I think may have been improved when I started keeping track of CO2 and keeping my windows open. (I don't spend most of my time outside and I certainly don't sleep outside; outside levels might be 450 but inside levels even with my mitigations are usually around 700)

Like so many things I think it is a small effect; it's not like I can go anywhere for a week to experience 300ppm air.

I haven't gone to the levels of designing experiments and data tracking on myself. The fact that I've lived with allergies and a broken nose most of my life probably hasn't helped my personal respiration characteristics.

> by applying heat

More heat than is common for home appliances I know! A commonly referenced stat is 825 C. There's really a gradient: https://en.m.wikipedia.org/wiki/Calcium_carbonate#Calcinatio...

Ah yes, with "heat" I meant a nice fire.