The SpinChem® Rotating Bed Reactor (RBR) retains the solid phase as a packed bed inside the rotating cylinder. As the RBR spins, a continuously circulating flow develops. Reaction solution is rapidly aspirated from the bottom of the vessel, percolated through the solid phase and quickly returned to the vessel. By the intelligent design of the SpinChem® RBR and vessel, the axial mixing and convective transport are maximized. The resulting efficient mass transfer minimizes reaction time, and boosts product yields. This holds even for liquids that are immiscible or of different viscosity, as well as for reactions demanding distribution of dissolved gases.