Processing of the first core of FBTR for plutonium recycle to the reactor will be required in near future. PUREX based reprocessing flowsheets are being developed at the laboratory for closing the fuel cycle. Reprocessing of Plutonium rich FBTR fuel (70% Pu for the first core) is special in several respects e.g., aqueous solutions bearing large percentage of fissile Pu have to be processed in small batches unlike the reprocessing of PHWR/LWR fuels where Pu content remains with in a few percent. Process upsets like plutonium polymerization, disproportionation, second organic phase formation and criticality in reprocessing facility have to be avoided in all conditions. First extraction cycle of a proposed unique three cycle high plutonium flowsheet was analysed for parametric sensitivity using a 2(N) factorial design and safe operating limits were established for the process to remain stable even during operational deviations arising out of random variations and anticipated fault sequences. In this paper, results of the sensitivity analysis are presented.