Вид документа : Статья из журнала Шифр издания : 54/P 78 Автор(ы) : Podval'naya N. V., Volkov V. L. Заглавие : Composition and Formation Kinetics of Sodium Polyvanadates in Vanadium(IV, V) Solutions Место публикации : Russian Journal of Inorganic Chemistry. - 2006. - Vol. 51, № 3. - С. 357-361: il. Примечания : Bibliogr. : p. 360-361 (17 ref.) ISSN: 0036-0236 ББК : 54 Предметные рубрики: ХИМИЧЕСКИЕ НАУКИ Ключевые слова (''Своб.индексиров.''): поливанадаты Аннотация: We study how VO2+ ions affect the composition and formation kinetics of polyvanadate precipitates in solutions with 1 ≤ ç ≤ 3 at 80–90°C. The compounds have the general formula Na2.1 – xHı O31 – δ ·nH2O (0 ≤ x ≤ 1.1, 0.2 ≤ y ≤ 2.3, 0.1 ≤ δ ≤ 1.4). The maximal vanadium(IV) concentration in the precipitates (y = 2.2 and 2.3) is achieved for the V4+/V5+ ratio in the solution equal to 0.5 and 0.3 and pH of 1.7 and 3.0, respectively. The polyvanadate precipitation at pH 1.7 has a long induction period, which is not observed when V4+/V5+ 0.02. In the solutions with pH 3.0, the precipitation occurs only when VO2+ are added. The processes are controlled by second-order reactions on the polyvanadate surface Доп.точки доступа: Volkov, V. L.; Волков Виктор Львович