That makes me wonder: Can you take a car's catalytic converter and fit it onto a fireplace's stovepipe? It seems like it should be a simple fix for lowering the amount of soot that gets out
Generally the stoves are designed specially for this. The stove burns hotter and may have a second combustion chamber. DIYers welding in the catalytic converter from a car is not the norm and not expected to be safe, but I bet there are some hackers who have made it work.
[0] https://ambassadorfireplaces.com/the-difference-between-cata...