Kinetics of Primary Nanoparticle Agglomeration in Precipitation of Silver



The precipitation kinetics of silver was studied using a lab-scale batch crystallizer with special attention to characterization of agglomeration of primary nanoparticles. The vessel was operated at different feed concentrations, molar ratios, and stirrer speed. Nucleation, volume average crystal growth rates, and agglomeration kernels were determined. Empirical relations were obtained between the rates of the different crystallization steps with supersaturation, magma density, and energy dissipation rate. The results show that larger crystals will be obtained at high supersaturation due to dominance of agglomeration, because the rate of agglomeration also increases with supersaturation, thereby suppressing the primary nucleation rate and enhancing the observed average volume growth rate.