4A Zeolite was synthesized using rice husk ash (RHA) as a raw material in a microwave-assisted hydrothermal synthesis. Two new procedures were proposed: procedure A, using RHA as the raw material, and procedure B, using the depolymerized RHA. Both procedures were performed using microwave-assisted hydrothermal synthesis, and neither synthesis required an aging time. Crystallinities of over 90 and 80% were reached at 100 ºC after 30 min of microwave heating for procedures A and B, respectively. The obtained zeolites were used as warm mix asphalt additives, and the performance of the zeolite obtained from procedure A was better. Additionally, the zeolite obtained from procedure A and commercial silane were used separately as asphalt-aggregate adhesion promoter. An increase in the adhesion percentage from 30% of a blank sample to 94% was observed.
Keywords:
4A zeolite; rice husk ash; microwave-assisted synthesis; aging time; warm mix asphalt additives
