The work concerns the possibility of the use of secondary waste from waste incineration processes for the production of zeolites. The study used fly ash and slag from national waste incineration plants. The test materials were subjected to hydrothermal alkaline activation in aqueous solution of sodium hydroxide, the molar concentrations of the various variants. The research revealed the usefulness of this type of material for the synthesis of zeolites –obtained sodalite. Presents the results of analyzes of the SEM / EDS and XRD for the most efficient synthesis processes.