3D structure of oil droplets in hardened geopolymer emulsions

Geopolymer (GP) cements have the ability to integrate huge amounts of organic oils by direct emulsion in the fresh paste. Moreover, the oil emulsion remains stable during GP hardening. This allows to design tailored GP/oil (GEOIL) composites for an array of industrial applications. Using 3D X‐ray micro‐Computed Tomography (micro‐CT), this research determines the spatial distribution of an industrial oil emulsion inside a GP cement (emulsification in the fresh state, imaging in the hardened state), depending on the oil volume fraction (from 5% to 60% total volume). The oil droplet size distribution, mean distance between droplets, and connectivity of the oil system are determined quantitatively. 3D X‐Ray micro‐Computed Tomography (micro‐CT) provides the spatial distribution of an oil emulsion inside a geopolymer (GP) cement (emulsification in the fresh state, imaging in the hardened state), depending on the oil volume fraction (from 5 to 60% total volume). For 30 vol% oil and more, the oil volume has a significantly greater connectivity than for 5, 10 or 20 vol% oil. The minimal percolation threshold is calculated from the images at a value of 27.0 %. This means that below 27.0%, no percolation of the oil network is achieved.