Produced by: Document Transformation Technologies Organised by Event Dynamics ALKALINE HYDROTHERMAL ZEOLITES SYNTHESIZED FROM

A co-disposal reaction was used wherein fly ash (FA) was reacted with acid mine drainage (AMD), to collect filtrates for zeolite synthesis. The Si and Al contents of the fly ash (FA) filtrates were used as precursor species for the alkaline hydrothermal conversion of the fly ash filtrates into zeolites. These filtrates were then analysed by XRF spectrometry for quantitative determination of SiO2 and Al2O3. The [SiO2]/[Al2O3] ratio obtained in the filtrates range from 1.4 to 2.5. The [SiO2]/[Al2O3] ratio was used to predict whether the fly ash filtrates could successfully be converted into faujasite zeolitic material by the synthetic method of Rayalu et al. (1). If the [SiO2]/[Al2O3] ratio is higher than 1.5 in the co-disposal filtrates, it favours the formation of faujasite. The zeolite synthesis included an alkaline fusion of the co-disposal filtrates, followed by aging for eight hours and hydrothermal conversion by crystallisation at 100 ºC. Different variables were investigated during the synthesis of zeolite to ascertain their influence on the end product. These variables include the amount of water in the starting material, composition of fly ash related starting material and the FA:NaOH ratio used for fusing the starting material (2,3)