ABSTRACT

Industrially produced metakaolin may contain raw kaolin residues. Therefore, the aim of this work was to determine the impact of kaolin remains on the metakaolin and the final geopolymer quality. A series of mixtures based on metakaolin (Mefisto L05 by CLUZ Nove Straseci, Czech Republic) was prepared with the 0-60 wt% gradual addition of raw kaolin, and the mechanical strength of the final geopolymer products was tested. It was found that up to a 20 wt. % amount of kaolin in metakaolin does not weaken the geopolymer’s performance. Moreover, a geopolymer made of metakaolin with 2-4 wt% of kaolin showed slightly better mechanical properties than the geopolymers made from metakaolin itself.