Effect of the fusion and aging process in the synthesis of zeotypes from fly ash

Abstract

In this study, we evaluate the use of a sample of fly ash from TERMOPAIPA (Boyacá, Colombia) as the starting material for the synthesis of zeotypes on laboratory scale through its transforming via alkaline fusion, using solid or water dissolved NaOH, followed by aging during 6, 12 and 24 h under static or ultrasound conditions prior to hydrothermal treatment during 6, 12 and 24 h of reaction time. Experimental data reveal that the method, state of alkaline fusion, temperature and time of reaction strongly affect the zeotype to be synthesized. Low-silica sodium zeotypes were synthesized, which include zeolite NaP1, faujasite, and traces of sodalite. The synthesis of zeotypes from fly ash represents an interesting alternative for the mitigation of the environmental problem associated to the disposal of industrial wastes. Therefore, fly ash-based zeotypes synthesized under optimum experimental conditions can be used in several applications for environmental waste treatment.