化学
焓
磷酸盐
磷酸铁
无机化学
标准生成焓变
标准生成焓
热力学
物理化学
有机化学
物理
作者
L. P. Ogorodova,Marina F. Vigasina,L. V. Mel’chakova,Vyacheslav S. Rusakov,D. A. Kosova,Dmitrii Ksenofontov,I. A. Bryzgalov
标识
DOI:10.1016/j.jct.2017.02.020
摘要
Abstract This paper presents the new data on thermodynamic properties of hydrous iron phosphate, vivianite. The thermochemical study of natural vivianite Fe 2.32 2 + Fe 0.33 3 + Mg0.35(PO4)2(OH)0.33·7.67H2O (Kerch iron ore basin, Republic of Crimea, Russia) was carried out on a high-temperature heat-flux Tian-Calvet microcalorimeter “Setaram” (France). The mineral was characterized by X-ray microprobe analysis, powder and single-crystal X-ray diffraction, thermal analysis, FTIR, Raman and Mossbauer spectroscopy. The value of Δ f H m 0 (T = 298.15 K) for natural vivianite was found to be −(5217 ± 11 kJ mol−1). The standard values of the entropy, enthalpy and Gibbs energy of formation at T = 298.15 K for vivianite of theoretical composition Fe 3 2 + (PO4)2·8H2O were calculated as (571.0) J (K mol)−1, −(5119 ± 19) kJ mol−1 and −(4439 ± 19) kJ mol−1 respectively.
科研通智能强力驱动
Strongly Powered by AbleSci AI