In a simple, but common case, the patterns and interfaces are self-similar or self-affine. They have similar features on many scales, leading to an invariable rugosity or fragmentation over the fractal scaling range. Physico-chemical phenomena on or around fractals cannot be described by the classical (usually differential) equations used for smooth shapes. Theoretical modeling and computer simulations can clarify the variety of patterns seen in experiments.

In my talk, I will discuss some practical, even industrial applications in the fields of particle technology, catalysis and chemical reactor engineering. The fundamental role of fractal symmetry in nature will be touched upon. It will also be shown how simple fractal architectures, inspired by the fractal shapes occurring in nature, can help to increase the performance of physical and chemical processes.