LAUSR

Abstract The conventional carbonisation (450-1000 °C) of whey powders gives totally unexpected results in terms of the mechanical integrity of the resulting carbons. Pieces of different geometries can be easily prepared by pouring the powders loosely into a mould. This green precursor adopts the shape of the predesigned mould at relatively low temperatures (120-150 °C) through the sintering of the whey particles surfaces. The shape of the pre-conformed pieces is preserved at least up to 1000 °C under N2 atmosphere, with a linear shrinkage of ca. 23%. The flexural strength and modulus of the resulting 3-D structured porous carbons are outstanding for a biomass derived carbon monolith, and their abrasiveness exceptionally low, similar to porous monoliths derived from phenolic resins. In addition, carbons obtained at temperatures above 800 °C develop a hierarchical porosity covering from micropores to macropores up to 400 μm granting high permeable structures. It is postulated that the presence of both lactose and whey proteins in whey powders is key for their atypical behaviour during carbonisation.