Carbothermic formation of boron nitride

Aydogdu, A
Sevinc, N
Formation of boron nitride by reaction of boric oxide with carbon and nitrogen was studied. It was found from the results of experiments conducted by holding BA-activated C mixtures under a flowing nitrogen atmosphere that formation of boron nitride was complete in 120 min at 1500 degreesC. After cleaning the reaction product from the ash of the activated carbon and from the unreacted B2O3 pure BN powder was obtained. B4C was found to exist as an intermediate species in the reaction products of the experiments in which BN formation was not complete. The results of experiments conducted with the objective of gaining an insight into the reaction mechanism by using different geometrical arrangements show that liquid 13,03 and solid carbon need not be in contact in the formation of BN from B2O3, C and N-2 and indicate that the reaction proceeds through a gaseous boron containing species which is most probably B2O3(g)


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Effect of CaCO3 on formation of hexagonal boron nitride (h-BN) was investigated by holding CaCO3 free and CaCO3 added activated carbon-boric oxide mixtures under nitrogen atmosphere at 1500 degrees C for 30-120 min. Amount of CaCO3 addition was varied in the range of 0-50 wt.% of the initial mixture. Products were characterized by powder X-ray diffractometry, FT-IR analysis, quantitative chemical analysis, scanning electron microscopy and BET specific surface area analysis. It was observed that calcium carb...
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Citation Formats
A. Aydogdu and N. Sevinc, “Carbothermic formation of boron nitride,” JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, pp. 3153–3161, 2003, Accessed: 00, 2020. [Online]. Available: