ON MOLTEN SALT FAST BREEEDER REACTOR USING 233UF,r 232ThF,r7UF MOLTEN SALT FUEL BY THE VARIATION OF 233U AND 232Th MOLE FRA CTION. A preliminary study on Molten Salt Fast Breeder Reactor using U233F4-Th232F4J UFmolten salt fuel by the variation of 233Uand 232Thmole fraction has been done. The objective ofthis research is to get the optimal design based on numerical calculation of the Molten SaltReactor as a type of the advance nuclear reactor using composition variation of molten salt fuel.In this research, the mole fraction of 233Uand 232Thisotopes in the molten salt fuel was variatedto obtain such parameters of nuclear reactor design including the critical condition, negativefeedback power reactivity, high conversion ratio, and high fuel burn up. This calculation wasdone by using the SRAC 2003 comfuter code. The calculation result indicates that the optimumcomposition is obtained at 6,6% 23 UF4, 59,4% ThF4 (10% mole fraction of U-233 towards fuelmaterial) and 34% 7UF mol fuel fraction. This composition obtain the flat k-effective values thatare 1,044069 at BOL and 1,0036910 at EOL, and the fuel burn up is reached at 200.000MWD/ton, which is use 2,0626 x 10.4 buckling geometry for cylindrical fuel geometry. Theconfiguration is adequate the standard safety criteria based on neutronic design criteria which ishave the negative reactivity both of by temperature, that is -3 x 1O-5/K at BOL and -9 x 10·6/K atEOL and also the fuel void fraction increased.Kevwords: Molten Salt Reactor, mole fraction variation, molten salt fuel, k-effective value, highburn up, conversion ratio, reactivity coefficient. Andi PJ, Andang Widi Harto; Program Studi Teknik Nuklir, Jurusan Teknik Fisika, Fakutas Teknik UGM
