on the struvite precipitation process and the suspended particles trigger heterogeneous nucleation which leads to rapid crystal growth on the surface of the MgO particles. In addition, as the magnesia dissolution is controlled by surface reaction, it is assumed that there is a high concentration of Mg2 þ ions around the surface of the particles which may favor struvite precipitation. However, this hypothesis has not yet been demonstrated, and future work should focus on examining local crystallization on the surface of suspended particles.
Therefore, local conditions within the suspension appear to greatly influence crystal growth and the properties of the final product.
Acknowledgments
This study was financially supported by the ANR-PHOSPHO’R project. The authors are grateful to Professor Matthias Kind for fruitful discussions about this study.