Preparation of Inorganic Compounds At Near Room Temperature by the Direct Conversion of Borate Glass in Solutions of the Corresponding Anions
The preparation of alkaline-earth chromate, selenite, and stannate compounds at near room temperature by the direct conversion of borate glass in aqueous solutions of the corresponding anions was investigated. Borate glass particles (150-300 μm) with the composition 20Na 2O. 20CaO. 60B 2O 3 or 20Na 2O. 20BaO. 60B 2O 3 (mol%) were prepared by conventional methods and immersed in dilute solutions of K 2CrO 4, K 2SeO 3, or K 2SnO 3 at 37°C. The conversion of the glasses was monitored using weight loss and pH measurements, while X-ray diffraction (XRD), X-ray fluorescence, and scanning electron microscopy were used to characterize the structure and composition of the products. After a reaction for 140-320 h, porous crystalline products identified by XRD as CaSeO 3.H 2O, CaSnO 3.3H 2O, BaCrO 4, and BaSeO 3 were obtained. The conversion of fibers (0.5-1.0 mm in diameter) of the Na 2O-BaO-B 2O 3 glass in K 2CrO 4 solution was pseudomorphic. The kinetics and mechanisms of the conversion process, as well as the structure of the products, are discussed.
W. Huang et al., "Preparation of Inorganic Compounds At Near Room Temperature by the Direct Conversion of Borate Glass in Solutions of the Corresponding Anions," Journal of the American Ceramic Society, vol. 91, no. 7, pp. 2105-2111, American Ceramic Society, Jul 2008.
The definitive version is available at http://dx.doi.org/10.1111/j.1551-2916.2008.02425.x
Mining and Nuclear Engineering
Materials Science and Engineering
Keywords and Phrases
Alkaline earths; Aqueous solutions; Borate glass; Conventional methods; Conversion process; Dilute solutions; Direct conversions; Kinetics and mechanisms; Ph measurements; Room temperatures; Stannate; Weight loss; X-ray diffractions; X-ray fluorescences; XRD
International Standard Serial Number (ISSN)
Article - Journal
© 2008 American Ceramic Society, All rights reserved.