Preparation of geopolymer from fluidized bed combustion bottom ash

• Published in: Journal of materials processing technology Vol. 200; no. 1; pp. 265 - 270
• Main Authors: Slavik, R., Bednarik, V., Vondruska, M., Nemec, A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 08.05.2008
• Subjects: Acid resistance; Compressive strength; Fluidized bed combustion bottom ash; Freeze-thaw resistance; Geopolymer; Wet-dry resistance; Geopolymer; Freeze-thaw resistance; Compressive strength; Wet-dry resistance; Acid resistance; Fluidized bed combustion bottom ash
• ISSN: 0924-0136
• DOI: 10.1016/j.jmatprotec.2007.09.008

This study has shown that it is possible to use fluidized bed combustion bottom ash (FBC-BA) without any thermal activation as a partial- or full-replacement for kaolinitic raw material in geopolymerization. Test specimens prepared from FBC-BA have reached compressive strength of almost 50 MPa after 90 days of hardening. After 50 freeze-thaw cycles, the compressive strength of test specimens has not decrease below 80% of compressive strength of unaffected reference specimens, which represents an acceptable freeze-thaw resistance. Testing of wet-dry resistance has shown that wet-dry cycles cause an increase of the compressive strength values. Testing of acid resistance of prepared geopolymer specimens has shown that replacement of usual kaolinitic raw material by FBC-BA results in slight increase of leachability.