The present study investigated the vaporization kinetics of MgCl2, CaCl2 and their binary melts in a fluidized bed at 1073-1273 K, and developed a vaporization model for the binary melts to explore the possibility of achieving enhanced vaporization rate for the feedstock containing CaO greater than 0.2 wt%. The vaporization rate constant of MgCl2 is more than seven times than that of CaCl2 at 1273 K. The vaporization rate of the binary melt was significantly affected by the composition, a small quantity of CaCl2 can remarkably deteriorate the overall vaporization rate. Experimental results coincide well with the numerical simulation by the vaporization model which regards the evolution of vaporization rate with melts composition. A correlation between the necessary operation temperature and the CaO/(CaO + MgO) of the feedstock was proposed. Predictions reveal that a similar vaporization rate for 0.2 wt%-0.4 wt% CaO content feedstock with 0.2 wt% could be achieved at lower than 1365 K. (C) 2016 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.