To　do　further　research　on　the　mass-transfer　mechanism　in　rotating　packed　bed　(RPB),　dynamics　of　droplets　in　a　RPB　are　studied　by　an　analytical　approach　combined　with　a　series　of　laboratory　measurements.　Based　on　the　results　of　the　fluid　dynamics,　mathematical　models　of　mass-transfer　coefficient　and　mass-transfer　process　in　RPB　are　proposed,　respectively.　Mass-transfer　experiments　in　RPB　are　also　carried　out　using　ethanol-water　solution.　By　comparison,　the　results　of　simulation　agree　well　with　that　of　the　experiment,　which　demonstrate　that　both　hydrodynamic　model　and　mass-transfer　models　can　better　describe　the　real　conditions　of　RPB.　(c)　2014　American　Institute　of　Chemical　Engineers　AIChE　J,　60:　2705-2723,　2014