SciELO - Scientific Electronic Library Online

 
vol.40 número4A Laboratory experiment for undergraduate instruction: non deal flow in tubular vesselsBiological sulphate removal in acid mine drainage using anaerobic fixed bed reactors with cheese whey as a carbon source índice de autoresíndice de materiabúsqueda de artículos
Home Pagelista alfabética de revistas  

Servicios Personalizados

Articulo

Indicadores

  • No hay articulos citadosCitado por SciELO

Links relacionados

  • En proceso de indezaciónCitado por Google
  • No hay articulos similaresSimilares en SciELO
  • En proceso de indezaciónSimilares en Google

Bookmark


Latin American applied research

versión impresa ISSN 0327-0793

Resumen

ROBLEDO MUNIZ, J. G. et al. Synthesis and characterization of high silica zeolites from coal fly ash(CFA): two cases of zeolite syntheses from the same waste material. Lat. Am. appl. res. [online]. 2010, vol.40, n.4, pp. 323-328.. ISSN 0327-0793.

Zeolites H/β and H/ZSM-11 were synthesized by the crystallization hydrothermal method (CH), using coal fly ash (CFA). Tetraethylammonium hydroxide (TEAOH), tetrapropylammonium bromide (TPAB) and tetrapropylammonium hydroxide (TPAOH) were used as structure-directing agents (SDA). The optimum conditions used in the experimentation were 140 °C and NaOH/CFA ratio=1.2 (wt/wt), during the crystallization hydrothermal method (CH), and microwave-assisted heating (MH) was used in some experiments. The structure and crystallinity of the synthesized materials were analyzed by X-ray diffraction, where the formation of the β and ZSM-11 zeolites was confirmed. The morphology of the obtained zeolites was observed by the scanning electron microscope technique. It was observed spheroidal particles for the ZSM-11 zeolite and ellipsoidal particles for the β zeolite, respectively. Both zeolites were ion exchange treated, in order to obtain the protonated form. Finally, the thermal stability and the loss of weight of the modified β zeolite were determined by using the termogravimetric and differential thermal analysis techniques. The modified zeolites were stable in the range of most gas chemical reactions (300-500 °C).

Palabras llave : Zeolite H/β; Zeolite H/ZSM-11; Crystallization Hydrothermal Method; Coal Fly Ash. Structure-Directing Agents.

        · texto en Inglés     · pdf en Inglés