The Liquid Tin Process was investigated for its ability to reprocess irradiated carbide fuel from Fast Breeder Reactors. In this process the spent fuel is dissolved in liquid tin at 1500°C, and separation from fission products is expected by first evaporating off the volatile fission product elements, followed by a nitriding step during which the U and Pu are expected to form the nitrides and precipitate, leaving the fission products either in solution in tin, or as nitrides that float. A flowsheet was developed for testing the individual unit operations involved. UC was dissolved and reprecipitated as either UN or U(C,N). The behaviour of a representative set (Cs, Sr, La, Pr, Ce, Ru, Mo, Zr, Pd) of fission products in liquid tin was studied. A high temperature liquid metal filtration system was developed for separating the precipitates from the fission product containing liquid tin solution. Separation capability of the process was finally tested by "reprocessing" simulated spent carbide fuel which was prepared by arc melting. The two fission products which could not be separated were Mo and Zr. The solubility of Mo in liquid tin is extremely low, and it therefore reports with the fissile material precipitate. Zr coprecipitates with uranium due totheir mutual miscibility. Plutonium was found to partition between the precipitated UN phase (1.5 wt3S average) and a Pu-rich (U,Pu)Sn, intermetallic phase.