Copper ions distribution in synthetic copper-zinc hydrosilicate

Abstract

Copper ions distribution in the structure of synthetic copper-zinc hydrosilicate of zincsilite structure, obtained non-hydrothermal synthesis have been studied. Zinesilite is referred to the layered silicates of smectite group and is described by the formula Znx (Zn3-x □x) [Si4O10](OH)2.nH2O, where Zn3-x—are the ions located in the octahedral positions of layers, formed by two sheets of [Si4O10] tetrahedrons; Znx are zinc ions in the interlayer; □x are the cation vacancies. Two types of copper ions were distinguished in accordance with the character of their interaction with hydrogen: (1)—substituting zinc ions in the octahedral positions of layers; (2)—substituting zinc ions in the interlayer. These two types of copper ions display the following properties when reacting with hydrogen: (1)—copper ions in octahedral positions start to be reduced at temperatures 553–573 K, and at 723 K reduction degree is 50%; (2)—copper ions from interlayer start to be reduced at 503–533 K with a constant energy of activation, and their reduction may be complete at this temperature.