Couldn’t you just dissolve magnesium in carbonic acid, then boil off the supernatant? I realize that would leave the crystalline MgCO3 — not the amorphous anhydrate — but couldn’t you get there by driving the water off and reducing the crystals by physical grinding?
One of the interesting aspects of nanotechnology is the substantial increase of surface area. Physical grinding wouldn’t approach it, but if it did it would be much more costly.
I think the “discovery” in there is the usage of high pressure to make the manufacturing process much more efficient. This is more a question of thermodynamics than chemistry.
Irony is that this would prove the falsity of fossile fuel equal globla warming because fossile fuels are made in a natural earth high pressure environment difficult to reproduce when using corn to synthesize.
All matter of control and coopting.