Isn't calcium production one of the major contributors to atmospheric CO2 - something like 8% globally due to cement? Would this process be a net benefit or just move the footprint further back in the chain?
Possibly, but catalysts are usually not required in anything like the same quantity that the process feedstocks are - they are only replaced due to attrition and wear, because the point of a catalyst is that it's not consumed in the desired chemical reaction
The reason cement is a major contributor to CO2 emissions is because of how much cement we produce. I don't know the lifetime or effectiveness of this catalyst, but typically you only need a tiny amount of catalyst to start a reaction and the catalyst material can be used over and over for a long time.
We produce a lot of it, *and* it has high CO2 emissions. The chemical reaction that gives concrete strength releases CO2.