ShrinkingcoreModell
The shrinking core model, sometimes written shrinking-core model, is a mathematical framework used to describe heterogeneous gas-solid reactions in which a solid particle reacts with a fluid and the unreacted core shrinks as the reaction proceeds. It is widely used in hydrometallurgy, mineral processing, catalysis, and environmental engineering to interpret leaching, reduction, oxidation, and solid-gas interactions. In German-language sources the term appears as Shrinking-Core-Modell.
The model assumes a single, homogeneous particle with a fixed initial shape, commonly spherical. The reaction
Let X denote the fraction of solid that has reacted, r the radius of the unreacted core,
Applications include ore processing, leaching, and catalytic or environmental processes involving solid particles. Limitations involve assumptions