2014-11-182014-11-182008-09MAIA, A. A. B.; ANGELICA, R. S.; NEVES, R. F. Estabilidade térmica da zeólita A sintetizada a partir de um rejeito de caulim da Amazônia. Cerâmica, São Paulo, v. 54, n. 331, p. 345-350, jul./set. 2008. Disponível em: <http://www.scielo.br/pdf/ce/v54n331/a1254331.pdf>. Acesso em: 31 jul. 2014. <http://dx.doi.org/10.1590/S0366-69132008000300012>.0366-6913https://repositorio.ufpa.br/handle/2011/6085Zeolite A was calcined at 200, 400, 600, 800 and 1000 °C for 2h to evaluate its thermal stability. The zeolite A was synthesized using kaolin waste from kaolin processing industries for paper coating located in the Amazon region. Both zeolite A and further calcined products were characterized by X-ray diffraction analysis and scanning electron microscopy. The zeolite A structure remained stable up to 600 °C, where only small variations in peak intensities were observed. At 800 °C the diffraction pattern still exhibited zeolite A but with the absence of some peaks. At 1000 °C nepheline, mullite and probably sodalite were formed. The zeolite A was also heated at 900 and 950 °C to check the two exothermic peaks observed in the DTA curve. The X-ray diffraction analysis indicated the presence of nepheline, sodalite and mullite.porAcesso AbertoSínteseEstabilidade térmicaZeólita AZeolitosCaulimRejeito de caulimBeneficiamento de minérioAmazônia brasileiraArtigo de Periódico