ZEOLITE FORMATION IN CLASS-F FLY-ASH BLENDED CEMENT PASTES

Zeolite formation in Class F fly ash blended cement pastes is under investigation. A Na-P type zeolite and Zeolite Y were synthesized from Class F fly ash and NaOH solution after 2 days of aging at room temperature and 6 days of curing at 80-degrees-C. However, no zeolites formed when KOH was used. In additional experiments, a Na-P type zeolite, Zeolite Y, and chabazite developed in cement pastes blended with Class F fly ash and NaOH solution which had been aged 2 days at room temperature and then cured 6 days at temperatures ranging from room temperature to 90-degrees-C. Seeding the pastes with natural zeolites was also investigated.