Hydrothermal synthesis and thermodynamic properties of 2CaO·3B2O3·H2O.

Authors :: Liu, Z.
Huang, H.
Zuo, C.
Source :: Journal of Thermal Analysis & Calorimetry; Aug2007, Vol. 89 Issue 2, p655-658, 4p, 1 Diagram, 3 Charts, 2 Graphs
Publication Year :: 2007
Abstract: 2CaO·3B<subscript>2</subscript>O<subscript>3</subscript>·H<subscript>2</subscript>O which has non-linear optical (NLO) property was synthesized under hydrothermal condition and identified by XRD, FTIR and TG as well as by chemical analysis. The molar enthalpy of solution of 2CaO·3B<subscript>2</subscript>O<subscript>3</subscript>·H<subscript>2</subscript>O in HCl·54.572H<subscript>2</subscript>O was determined. From a combination of this result with measured enthalpies of solution of H<subscript>3</subscript>BO<subscript>3</subscript> in HCl·54.501H<subscript>2</subscript>O and of CaO in (HCl+H<subscript>3</subscript>BO<subscript>3</subscript>) solution, together with the standard molar enthalpies of formation of CaO(s), H<subscript>3</subscript>BO<subscript>3</subscript>(s), and H<subscript>2</subscript>O(l), the standard molar enthalpy of formation of −(5733.7±5.2) kJ mol<superscript>−1</superscript> of 2CaO·3B<subscript>2</subscript>O<subscript>3</subscript>·H<subscript>2</subscript>O was obtained. Thermodynamic properties of this compound were also calculated by a group contribution method. [ABSTRACT FROM AUTHOR]