So you've turned the pollution into a fine powder. Now what are you going to do with it?
"Roosegaarde claims that the firm did get diamonds from pollution dust made, but as the process required so much energy it didn’t chime with the firm’s environmentally friendly ethos. Instead, they sell jewelry featuring little blocks of compressed pollutants."
Not a good answer.
Ship it to the US as a key ingredient in blackface? Oh wait...