Effect of Solution Stoichiometry on BaSO4 Crystallization from Turbidity Measurements and Modeling

The impact of solution stoichiometry on the nucleation and growth of BaSO was studied by measuring solution transmittance and subsequent fitting to a crystallization model. Our results show that a large excess of either Ba or SO ions inhibits both the nucleation and growth of BaSO. However, for a small excess of Ba, the growth is enhanced. The dependence of nucleation and growth rates on supersaturation and solution stoichiometry was captured by a semiempirical rate model. Hence, the solution stoichiometry is a highly relevant parameter while studying all aspects of BaSO crystallization, and it could be worthwhile to examine other minerals similarly.