That doesn't change anything. You need a huge amount of energy to remove CO2 from the atmosphere because CO2 is a tiny constituent part of Air (~400ppm) - that means one has to move a million molecules of air across a collector (whatever that is) to remove 400 molecules of CO2. You can't do that without huge amounts of energy and a huge surface area for your collector ... on any human timescale.
Oh man. Somebody always gets a way to make problems out of the entropy of diffusion. It increases with the log of the concentration, so whatever problem you estimate to happen, it can be worked around.
On the case of silicates, a trivial work around is to just spread them around and let the same diffusion bring the CO2 into them.
What makes you think it would be significantly easier to filter out the carbolic acid from the ocean? The same difficulties apply, and water is much more viscous than air.
Not practically. We are talking about huge scales, such that the industrial production, transport, etc., would be as much of an environmental disaster as what it's trying to solve.
