We have had very good success with Matrix Breakdown (Their POG) on Wool carpet from the regualr soot sinders. Usually but not always a good degrease is going to take care of your soot problems. Most of your fire restoration products designed for Soot are based around a degreaser. But Like John Watson dry vac first. Might try a suction only vac, as a beater bar may work it into the pile rather than removing it readily available.