[01] Raquel R. Alcântara, Chemical and Environmental Center, Nuclear and Energy Research Institute, São Paulo, Brazil. [02] Juliana C. Izidoro, Chemical and Environmental Center, Nuclear and Energy Research Institute, São Paulo, Brazil. [03] Denise A. Fungaro, Chemical and Environmental Center, Nuclear and Energy Research Institute, São Paulo, Brazil.

Coal fly ash is generated in large amounts in Brazil; therefore, its productive reuse is important. Zeolite was synthesized from coal fly ash obtained from the Presidente Medici Thermal Power Plant by alkaline conventional hydrothermal treatment and then modified using hexadecyltrimethylammonium (HDTMA). Coal fly ash (CFA), non-modified (ZCA) and surfactant-modified (SMZ) nanozeolites products were characterized to obtain chemical and mineralogical composition, surface area, and total and external cation-exchange capacity among other parameters. PXRD patterns revealed that zeolite P1 and hydroxysodalite were the dominant contents of synthesized zeolitic nanomaterials. Due to the zeolitazation, ZCA and SMZ exhibited a greatly enhanced cation exchange capacity and BET area compared to coal fly ash. The SMZ presented negative charge indicating the formation of a partial bilayer of HDTMA on exchangeable active sites on the external surface of unmodified nanozeolite. The characterization results show no changes occurred in ZCA after their surface modification with surfactant.

Coal Fly Ash, Surfactant, Surface Modification, Nanozeolite Nanomaterial

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