Author(s)

Neven Ukrainczyk, Oliver Vogt, Eduardus A. B. Koenders

Technische Universitat Darmstadt, Institute of Construction and Building Materials, Darmstadt, Germany.

Geopolymers are alternative binders made solely from industrial by-products and/or natural alumino-silicates, comprising no traditional cements. Reactive transport processes in geopolymer materials play a crucial role in both the degradation process of building materials as well as in the containment of hazardous wastes. A numerical model is presented for solving transport coupled to nonlinear ion-exchange equilibria between solid-liquid phases. Bound alkalies provide the geopolymer paste with a large reservoir of exchangeable (soluble) alkalies that allow for a more gradual drop in pH of the pore solution, as compared to a sudden drop when considering only diffusion transport mechanism. The model is robust enough to handle non-linearity of the ion-exchange equations, and presents a more reliable way to obtain long term durability predictions of geopolymer materials.

Geopolymers, Numerical Modeling, Reactive Transport, Leaching, Durability

Ukrainczyk, N. , Vogt, O. and Koenders, E. (2016) Reactive Transport Numerical Model for Durability of Geopolymer Materials. Advances in Chemical Engineering and Science, 6, 355-363. doi: 10.4236/aces.2016.64036.