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  • 1 Dipartimento di Chimica Università Della Calabria Arcavacata di Rende 87030 Rende CS Italy
  • 2 Industrial Chemistry Research Institute 01-793 Warsaw, Rydygiera 8 Poland
  • 3 Dastec, Facoltà di Architettura Università di Reggio Calabria Via Diana 4 89125 Reggio Calabria Italy
  • 4 Facultés Universitaires Notre Dame de la Paix Laboratoire de Catalyse 5000 Namur Belgium
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By means of simultaneous DTA-, TG- and DTG-technique, the silicate gels and the MFI crystals obtained from these gels have been investigated. The gels have been prepared in presence and in absence of tetrapropylammonium cation (TPA+) and with Li+, Na+, NH4+ and K+ fluorides. In absence of TPA+ no thermal effects have been observed in Li+- and Na+-gels. The effects observed in the NH4+ -gel stem from a decomposition and release of inorganic phases: SiF4, NH4F, NH3. The DTA/DTG effects in the TPA+ containing gels and in the MFI crystals of monodisperse size are attributed to the decomposition of TPA+ cation. It can be concluded from these effects that the interaction between the gels and the TPA+ cation is rather weak. The interaction between TPA+ and MFI crystals obtained in fluoride medium is stronger than the interaction with crystals obtained from alkaline media. Similar thermal effects are obtained after grinding the long crystals to those having a large distribution of crystal sizes.

  • Impact Factor (2019): 2.731
  • Scimago Journal Rank (2019): 0.415
  • SJR Hirsch-Index (2019): 87
  • SJR Quartile Score (2019): Q3 Condensed Matter Physics
  • SJR Quartile Score (2019): Q3 Physical and Theoretical Chemistry
  • Impact Factor (2018): 2.471
  • Scimago Journal Rank (2018): 0.634
  • SJR Hirsch-Index (2018): 78
  • SJR Quartile Score (2018): Q2 Condensed Matter Physics
  • SJR Quartile Score (2018): Q2 Physical and Theoretical Chemistry

Manuscript Submission: HERE