Application of Weak Acid Resin process to the production of spherical and calibrated oxide precursor bearing uranium and americiumoverview of 10 years research at CEA

International audience; This paper is dedicated to the adaptation of the Weak Acid Resin process (WAR) to the elaboration of uranium-americium mixed oxide microspheres as precursors for the fabrication of Americium Bearing Blankets (AmBB). It describes successive developments of WAR process from lanthanide simple oxide synthesis to actinide(s) bearing mixed oxide preparation. Recent studies demonstrated the scientific feasibility of the preparation of a dense uranium-americium mixed oxide pellets with 10 $_{at}$% of Am vs heavy metal and with 95 % of theoretical density (TD) from those innovative microsphere precursors