Kinetic study on polyethylenimine-assisted reactive crystallization of monodisperse strontium sulfate microcrystals

Double-jet reactive crystallization of SrSO₄ was carried out in the presence of polyethylenimine (PEI). A simple kinetic model of primary nucleation as well as crystal growth was investigated under the condition of producing monodisperse microcrystals. Furthermore, surface free energy in the solution of PEI was estimated. PEI addition causes growth inhibition leading to smaller sizes and modifies the Gibbs free energy gap required for occurring nucleation. The effect of polyethylenimine (PEI) addition on nucleation and growth of SrSO₄ is determined and a simple kinetic model is proposed. Time-dependent behaviors of crystal size and crystal number are statistically analyzed by a nonlinear least-square program. Kinetic aspects under the condition of obtaining monodisperse crystals are discussed.