(1) The Sherwood numbers at either tube wall probes or inner probes seem to be independent on the tube to particle ratio N. Meanwhile, the mass transfer is stronger at inner probes than that at tube wall probes. Two correlations of mass transfer j factor with Reynolds number are developed for data at wall probes and inner probes. Besides, it is found that mass transfer is enhanced with ordered pore structures in simple cubic packed beds when compared with that in random packed beds.