[Hyda247]

Hi! I’m a high schooler in an engineering capstone class, in which my group and I have decided to tackle the problem of global warming. We had the simple idea of putting a CO2 scrubbing tube on the end of a car exhaust pipe to attack the problem at the source. We plan to use soda lime as our filtering element. We bought a 3 pound bag of soda lime on Amazon. Because we have run into some potential safety issues with soda lime, we have yet to open the bag. How dangerous is the chemical and would it be safe to handle in a classroom? If it is too dangerous to use is there any other chemical we can use to scrub CO2 that’s not harmful?

Below is the chemical reaction between CO2 and soda lime and the specific product we ordered.

https://accessanesthesiology.mhmedical.com/content.aspx?bookid=974&sectionid=61586921

https://www.amazon.com/Jorvet-Soda-Lime-Lb-Each/dp/B01LWOJ574/ref=mp_s_a_1_3?crid=2KW8SUAJSLIPG&keywords=soda+lime&qid=1646702940&sprefix=soda+lime%2Caps%2C65&sr=8-3

[Corribus]

The biggest danger is that it's caustic and reacts with moisture. So, take steps to ensure that you don't breathe in the dust or get it in your eyes. Wear gloves. Use well-ventilated space, etc.

[DrCMS]

We had the simple idea of putting a CO2 scrubbing tube on the end of a car exhaust pipe to attack the problem at the source. We plan to use soda lime as our filtering element. We bought a 3 pound bag of soda lime on Amazon.

https://accessanesthesiology.mhmedical.com/content.aspx?bookid=974&sectionid=61586921

Have you tried any paper calculations to test how feasible your idea is?

I assume from your 3lb comment you are American - the average US car (is very uneconomical) producing about 411g of CO₂ per mile traveled. Your linked article say 100g of soda lime can absorb about 26L of CO₂ so your 3lb bag could absorb about 1½-2 miles worth of car emissions.  For a typical commute of 16miles each way you'd need a scrubber that held >60lb of soda lime that would need to be changed every day.

[Enthalpy]

More than in the lab, I worry about flying soda powder when the car exhaust blows through it.