Abstract: Adopting the technical route of experimental research combined with the industrial production,this paper determined the solubility of ferrous sulfate in water to explore its crystallization kinetics characteristics and investigate the filter cake liquid content with different crystal sizes.Simulation and prediction for the ferrous sulfate crystallization via the current vacuum adiabatic cooling batch crystallization process with seed crystal added were carried out,and the working equations of systematic vacuum degree,crystallization temperature,cooling rate and evaporation rate were obtained.The whole crystallization process does not produce new crystal nuclei,realizing the rapid growth of crystals.The crystal size of controlled crystallization is increased by 3.8 times than that of the current process.The amount of titanium liquid entrained in the filter cake is reduced by 48%,which effectively reduces the loss of titanium liquid.