Synthetic zeolites from lignite fly ash and biomass ash for agricultural applications
Maria Andreadi
Charalampos Vasilatos
The production of zeolites is one of the potential applications of fly ash production to obtain high value industrial products with environmental technology utilization. The synthesis of zeolite products from fly ash is analogous to the formation of natural zeolites from volcanic deposits or other high-Si-Al rocks,rich in amorphous phases, by the interaction of hot alkaline water on the glass fraction of the rocks. That zeolite development process may take thousands of years in order to form natural zeolites. In the laboratory, the process can be speeded up (to days or hours) for both volcanic and fly ash.
Previous studies have demonstrated the utilization of lignite fly ash Na bearing synthetic zeolitic materials for the removal of heavy metals from wastewater, for mine-water treatment and as soil amendments in acid mining soils. Since K is considered as a nutritient in agriculture KOH was selected as an activation solution, in order to develop a K-rich synthetic zeolite suitable for utilization in agriculture.
In the current study we are evaluating the results of the hydrothermal activation of lignite fly ash and biomass asses from Greece, by KOH in order to produce synthetic zeolites, for agricultural applications.
(EN)
