Naslov
Influence of alkalinity during the precipitation of gel on the nucleation of zeolite A

Autori
Antonić, Tatjana ; Subotić, Boris

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
1st Euroworkshop On Zeolites - "Zeolite Synthesis: From Dream to Production": Scientific Program and Abstracts / Francesco di Renzo - Poitiers : Federation of European Zeolite Associations, 1996, P3-p3

Skup
1st Euroworkshop On Zeolites - "Zeolite Synthesis: From Dream to Production"

Mjesto i datum
La Rochelle, Francuska, 17.03.1996. - 20.03.1996

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
zeolite A; alkalinity; alumosilicate gel; nucleation; crystallization

Sažetak
A series of aluminosilicate gels having the molar oxide composition: (3.31 + x) Na2OxAl2O3x2 SiO2x333.33 H2O, where x = 0, 0.069, 1.38, 2.07 and 2.763 were prepared by adding 50 ml of sodium silicate solution [(1.03 + x) Na2OxSiO2x55.55 H2O] into 100 ml of stirred sodium aluminate solution [1.25 Na2Ox Al2O3x222.22 H2O]. Before mixing, the solutions were preheated to the reaction temperature (80o C). After the precipitation was finished, each gel was diluted with 50 ml of hot (80o C) NaOH solution of appropriate concentration, so that the final batch composition was: 6 Na2OxAl2O3x2 SiO2x444.44 H2O. The gels prepared in the above mentioned way were stirred at 80o C until amorphous phase has completely been transformed to zeolite A. Kinetics of crystallization were studied by different methods such as: x-ray diffractometry, optical and scanning-electron microscopy, particle size analysis and chemical analysis of of the solid and liquid phase. Experimental results were analyzed and discussed in the terms of the influence of OH- ions on the formation of gels and on the number and distribution of nuclei in the gel phase and thus on the rate of nucleation of zeolite A from the gels prepared under different alkalinities.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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