Kinetika mehanohemijske sinteze barijum-titanata
Kinetics of mechanochemical synthesis of barium-titanate
Abstract
U ovom radu ispitivan je uticaj mehaničke aktivacije na sistem barijum oksid-titan dioksid. Mehanička aktivacija je vršena u vibro-mlinu u vremenskom intervalu od 30 do 440 minuta. Tokom aktivacije došlo je do reakcije polaznih komponenti u čvrstoj fazi, pri čemu je kao krajnji produkt dobijen barijum-titanat. Metode rendgenske difrakcije i spektrofotometrijske analize su korišćene radi identifikacije faznog sastava i kvantitativnog sadržaja komponenti tokom reakcije. Predložen je mehanizam sinteze barijum-titanata i utvrđeni su kinetički parametri.
In this paper the influence of mechanical activation on the system barium oxide - titan dioxide has been investigated. Also, the theoretic model of mechanochemical reaction has been introduced. Process of mechanical activation was conducted in vibro-mill in the 30 to 440 minutes interval. Solid state reaction has been noticed during the activation process. X-ray diffraction method has been employed in order to determine phase composition of mechanically activated mixtures. The process of milling could be divided into three stages: first stage-progressive destruction of reactant's crystal structure; second phase-nanocrystal structure formation as a consequence of defects introduction within crystal structure; third phase-obvious formation of a new phase and peak's intensities growth caused by crystal phase arranging. It was noticed that barium titanate was obtained successfully at the end of the milling process. Method of spectrofotometry has been chosen for determining the quantitative... ratio of starting components during the reaction. The authors suggested the synthesis mechanism of barium-titanate and established the kinetic parameters. Also, it was notices that the reaction between barium oxide and titan dioxide represents 'two-stages' reaction, which includes the formation of intermediate compound BaO*TiO2. Having in mind that the constant of reaction velocity of the process of intermediate compound formation is greater than constant of barium titanate formation, we can conclude that activation energy of first stage is less than activation energy of second process. Analysis of kinetics showed that the half-time synthesis of mentioned compound is 77.7 minutes, while at the end of milling process the reaction between starting reactants was complete.
Keywords:
rendgenska difrakcija / mehanička aktivacija / barijum-titanat / X-ray diffraction / mechanical activation / barium-titanateSource:
Tehnika, 2011, 66, 3, 367-371Publisher:
- Savez inženjera i tehničara Srbije, Beograd
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Institution/Community
Institut za tehnologiju nuklearnih i drugih mineralnih sirovinaTY - JOUR AU - Đorđević, Nataša AU - Obradović, Nina AU - Filipović, Suzana PY - 2011 UR - https://ritnms.itnms.ac.rs/handle/123456789/198 AB - U ovom radu ispitivan je uticaj mehaničke aktivacije na sistem barijum oksid-titan dioksid. Mehanička aktivacija je vršena u vibro-mlinu u vremenskom intervalu od 30 do 440 minuta. Tokom aktivacije došlo je do reakcije polaznih komponenti u čvrstoj fazi, pri čemu je kao krajnji produkt dobijen barijum-titanat. Metode rendgenske difrakcije i spektrofotometrijske analize su korišćene radi identifikacije faznog sastava i kvantitativnog sadržaja komponenti tokom reakcije. Predložen je mehanizam sinteze barijum-titanata i utvrđeni su kinetički parametri. AB - In this paper the influence of mechanical activation on the system barium oxide - titan dioxide has been investigated. Also, the theoretic model of mechanochemical reaction has been introduced. Process of mechanical activation was conducted in vibro-mill in the 30 to 440 minutes interval. Solid state reaction has been noticed during the activation process. X-ray diffraction method has been employed in order to determine phase composition of mechanically activated mixtures. The process of milling could be divided into three stages: first stage-progressive destruction of reactant's crystal structure; second phase-nanocrystal structure formation as a consequence of defects introduction within crystal structure; third phase-obvious formation of a new phase and peak's intensities growth caused by crystal phase arranging. It was noticed that barium titanate was obtained successfully at the end of the milling process. Method of spectrofotometry has been chosen for determining the quantitative ratio of starting components during the reaction. The authors suggested the synthesis mechanism of barium-titanate and established the kinetic parameters. Also, it was notices that the reaction between barium oxide and titan dioxide represents 'two-stages' reaction, which includes the formation of intermediate compound BaO*TiO2. Having in mind that the constant of reaction velocity of the process of intermediate compound formation is greater than constant of barium titanate formation, we can conclude that activation energy of first stage is less than activation energy of second process. Analysis of kinetics showed that the half-time synthesis of mentioned compound is 77.7 minutes, while at the end of milling process the reaction between starting reactants was complete. PB - Savez inženjera i tehničara Srbije, Beograd T2 - Tehnika T1 - Kinetika mehanohemijske sinteze barijum-titanata T1 - Kinetics of mechanochemical synthesis of barium-titanate EP - 371 IS - 3 SP - 367 VL - 66 UR - conv_2 ER -
@article{ author = "Đorđević, Nataša and Obradović, Nina and Filipović, Suzana", year = "2011", abstract = "U ovom radu ispitivan je uticaj mehaničke aktivacije na sistem barijum oksid-titan dioksid. Mehanička aktivacija je vršena u vibro-mlinu u vremenskom intervalu od 30 do 440 minuta. Tokom aktivacije došlo je do reakcije polaznih komponenti u čvrstoj fazi, pri čemu je kao krajnji produkt dobijen barijum-titanat. Metode rendgenske difrakcije i spektrofotometrijske analize su korišćene radi identifikacije faznog sastava i kvantitativnog sadržaja komponenti tokom reakcije. Predložen je mehanizam sinteze barijum-titanata i utvrđeni su kinetički parametri., In this paper the influence of mechanical activation on the system barium oxide - titan dioxide has been investigated. Also, the theoretic model of mechanochemical reaction has been introduced. Process of mechanical activation was conducted in vibro-mill in the 30 to 440 minutes interval. Solid state reaction has been noticed during the activation process. X-ray diffraction method has been employed in order to determine phase composition of mechanically activated mixtures. The process of milling could be divided into three stages: first stage-progressive destruction of reactant's crystal structure; second phase-nanocrystal structure formation as a consequence of defects introduction within crystal structure; third phase-obvious formation of a new phase and peak's intensities growth caused by crystal phase arranging. It was noticed that barium titanate was obtained successfully at the end of the milling process. Method of spectrofotometry has been chosen for determining the quantitative ratio of starting components during the reaction. The authors suggested the synthesis mechanism of barium-titanate and established the kinetic parameters. Also, it was notices that the reaction between barium oxide and titan dioxide represents 'two-stages' reaction, which includes the formation of intermediate compound BaO*TiO2. Having in mind that the constant of reaction velocity of the process of intermediate compound formation is greater than constant of barium titanate formation, we can conclude that activation energy of first stage is less than activation energy of second process. Analysis of kinetics showed that the half-time synthesis of mentioned compound is 77.7 minutes, while at the end of milling process the reaction between starting reactants was complete.", publisher = "Savez inženjera i tehničara Srbije, Beograd", journal = "Tehnika", title = "Kinetika mehanohemijske sinteze barijum-titanata, Kinetics of mechanochemical synthesis of barium-titanate", pages = "371-367", number = "3", volume = "66", url = "conv_2" }
Đorđević, N., Obradović, N.,& Filipović, S.. (2011). Kinetika mehanohemijske sinteze barijum-titanata. in Tehnika Savez inženjera i tehničara Srbije, Beograd., 66(3), 367-371. conv_2
Đorđević N, Obradović N, Filipović S. Kinetika mehanohemijske sinteze barijum-titanata. in Tehnika. 2011;66(3):367-371. conv_2 .
Đorđević, Nataša, Obradović, Nina, Filipović, Suzana, "Kinetika mehanohemijske sinteze barijum-titanata" in Tehnika, 66, no. 3 (2011):367-371, conv_2 .