This work investigated the mass transfer of a rotating packed bed (RPB) with emphasis on the effects of the packing's size, shape, material, and surface property. Experimental results show that there is no obvious relationship between a(t) and k(L)a. Among the various shapes of the packings, the mass transfer coefficients of Raschig rings and Intalox saddles are lower than those of the others, while the kLa of the wire meshes is the highest. As to materials, the mass transfer coefficients are similar for acrylic, glass, ceramic, and stainless steel beads. Besides, the kLa values of the hydrophobically treated packings are 8-27% lower than those of the original glass and ceramic packings. A modified correlation of kLa, which includes the effects of various packings, is proposed based on our RPB experimental results. Further, this correlation can also reasonably estimate most of the k(L)a data in the Higee literature.