I have a suggestion.

There's a resonant electromagnetic frequency at which carbon dioxide dissociates into a molecule of oxygen and a very reactive free carbon atom. What the carbon atom usually does is to grab the nearest oxygen molecule and bind to it, but not if it's offered a carbon bond as an alternative.

So if we provide a transparent flat carbon substrate and beam a tuned laser through from beneath, to skim the substrate surface along the underside, all carbon dioxide coming into contact with the surface will dissociate, the oxygen will remain in the gas and the carbon will build up the substrate surface. At around 100 atoms a second at any particular location if my sums are right, given an uninterrupted supply of 400ppm carbon dioxide blown along the gas-solid interface.

That's a deposition rate of 30cm a year building up the transparent solid carbon phase.

So with enough laser output tuned to the right frequency, and a 10x10km platform seeded with 10 atoms thickness of substrate to channel the energy, and some very heavy-duty fans blowing the air, I reckon we can sequester the whole of the UK's CO2 emissions in real-time.

Whether we can subsequently find a use for the annual foot-thick transparent hundred-square-kilometer carbon deposit which is left behind I'm not sure. We'd need to think of a use for that. Heavy duty double glazing panels perhaps.