The article canvasses both sequestration of the captured carbon, as well then continuing on to fuel synthesis. If fuel synthesis is not advisable, then sequester the carbon instead. I gave the costs for just carbon capture without proceeding to fuel synthesis, and if used purely for carbon sequestration, the process is a surprisingly way to generate negative emissions.
CO2 is returned to the atmosphere, yes, but it will reequilibrate to the ocean, over what appears to be a timeframe of twenty years or less, according to the data in Table 2. Fuel whose impact is a transient redistribution of CO2 between ocean and atmosphere is certainly better than one that adds new fossil carbon to the atmosphere.
"It is only produced with no CO2 emmissions as it is produced with eletricity produced by a nuclear reactor system."
Well, I'm interested in CO2 neutral fuels, not energy neutral fuels. The energy in the fuel has to come from somewhere.