Densification and crystallization behaviour of colloidal cordierite-type gels
Апстракт
Three cordierite-type gels were prepared from an aqueous solution of Mg(NO3)(2). a boehmite sol and silica sols of very small particle sizes. The effect of varying the silica particle size on the crystallization and densification behaviour was studied. Phase development was examined by thermal analysis and X-ray diffraction, while the densification behaviour was characterized by measuring the linear shrinkage of pellets. The activation energy of densification by viscous flow was determined using the Franckel model for non-isothermal conditions and a constant heating rate. The results show that spinel crystallizes from the colloidal gels prior to cristobalite, and their reaction gives alpha -cordierite. which is specific for three-phase gels. Decreasing the silica particles size lowers the cristobalite crystallization temperature and the alpha -cordierite formation temperature The activation energy of densification by viscous flow is lower and the densification more efficient. the small...er the silica particles are.
Кључне речи:
cordierite / sol-gel / densification / crystallization / activation energy of densificationИзвор:
Journal of the Serbian Chemical Society, 2001, 66, 5, 335-343Колекције
Институција/група
VinčaTY - JOUR AU - Petrović, R AU - Janaćković, Đorđe T. AU - Božović, B AU - Zec, Slavica AU - Kostic-Gvozdenovic, L PY - 2001 UR - https://vinar.vin.bg.ac.rs/handle/123456789/2431 AB - Three cordierite-type gels were prepared from an aqueous solution of Mg(NO3)(2). a boehmite sol and silica sols of very small particle sizes. The effect of varying the silica particle size on the crystallization and densification behaviour was studied. Phase development was examined by thermal analysis and X-ray diffraction, while the densification behaviour was characterized by measuring the linear shrinkage of pellets. The activation energy of densification by viscous flow was determined using the Franckel model for non-isothermal conditions and a constant heating rate. The results show that spinel crystallizes from the colloidal gels prior to cristobalite, and their reaction gives alpha -cordierite. which is specific for three-phase gels. Decreasing the silica particles size lowers the cristobalite crystallization temperature and the alpha -cordierite formation temperature The activation energy of densification by viscous flow is lower and the densification more efficient. the smaller the silica particles are. T2 - Journal of the Serbian Chemical Society T1 - Densification and crystallization behaviour of colloidal cordierite-type gels VL - 66 IS - 5 SP - 335 EP - 343 UR - https://hdl.handle.net/21.15107/rcub_vinar_2431 ER -
@article{ author = "Petrović, R and Janaćković, Đorđe T. and Božović, B and Zec, Slavica and Kostic-Gvozdenovic, L", year = "2001", abstract = "Three cordierite-type gels were prepared from an aqueous solution of Mg(NO3)(2). a boehmite sol and silica sols of very small particle sizes. The effect of varying the silica particle size on the crystallization and densification behaviour was studied. Phase development was examined by thermal analysis and X-ray diffraction, while the densification behaviour was characterized by measuring the linear shrinkage of pellets. The activation energy of densification by viscous flow was determined using the Franckel model for non-isothermal conditions and a constant heating rate. The results show that spinel crystallizes from the colloidal gels prior to cristobalite, and their reaction gives alpha -cordierite. which is specific for three-phase gels. Decreasing the silica particles size lowers the cristobalite crystallization temperature and the alpha -cordierite formation temperature The activation energy of densification by viscous flow is lower and the densification more efficient. the smaller the silica particles are.", journal = "Journal of the Serbian Chemical Society", title = "Densification and crystallization behaviour of colloidal cordierite-type gels", volume = "66", number = "5", pages = "335-343", url = "https://hdl.handle.net/21.15107/rcub_vinar_2431" }
Petrović, R., Janaćković, Đ. T., Božović, B., Zec, S.,& Kostic-Gvozdenovic, L.. (2001). Densification and crystallization behaviour of colloidal cordierite-type gels. in Journal of the Serbian Chemical Society, 66(5), 335-343. https://hdl.handle.net/21.15107/rcub_vinar_2431
Petrović R, Janaćković ĐT, Božović B, Zec S, Kostic-Gvozdenovic L. Densification and crystallization behaviour of colloidal cordierite-type gels. in Journal of the Serbian Chemical Society. 2001;66(5):335-343. https://hdl.handle.net/21.15107/rcub_vinar_2431 .
Petrović, R, Janaćković, Đorđe T., Božović, B, Zec, Slavica, Kostic-Gvozdenovic, L, "Densification and crystallization behaviour of colloidal cordierite-type gels" in Journal of the Serbian Chemical Society, 66, no. 5 (2001):335-343, https://hdl.handle.net/21.15107/rcub_vinar_2431 .