Nucleation behavior in the precipitation of a sparingly soluble salt - AgBr

摘要: Abstract Nucleation behavior during the early stages of precipitation a sparingly soluble salt (AgBr) was studied experimentally. Direct electron microscopy and light-scattering photometry were used to determine average diameter number AgBr nuclei. For given reactant addition rate R, nuclei increased at first, reached maximum, then started decrease. The slope ln-ln plot maximum versus R ∾ 1.5, indicating bulk-diffusion growth mechanism for 0.008–0.015 μm, changed with time. supersaturation ratio S, calculated from Gibbs-Thomson equation, showed same as that theoretical prediction. However, S values significantly smaller than critical value reported homogeneous nucleation These can be explained qualitatively by survival concept.