【摘要】 根据热力学计算原理,以高镁磷尾矿中主要物质白云石和氟磷灰石在硫酸水溶液中的高温PHT0计算为例,研究了Mg2+-Ca2+-H2CO3-H2O、CaCO3.MgCO3-SO42--H2O、Ca2+-F--H3PO4-H2O、Ca5(PO4)3F-SO24--H2O、Mg2+-H3PO4-H2O体系在高温与常温下的热力学平衡变化情况。结果表明,CaCO3.MgCO3和Ca5(PO4)3F在水溶液中的平衡常数K0随温度的升高而降低;二者在硫酸水溶液中的主要反应pH0随温度升高而降低,浸出反应需在较高酸度下进行;二者在酸性溶液中的溶解高温较常温下有较大迁移。更多还原

【Abstract】 According to the thermodynamics calculation principles,as examples of calculating PH0T values at high temperature on CaCO3·MgCO3 and Ca5(PO4)3 F in phosphate tailing with high magnesium content,the thermodynamic equilibriums variations of Mg2+-Ca2+-H2CO3-H2O,CaCO3·MgCO3-SO2-4-H2O,Ca2+-F——H3PO4-H2O,Ca5(PO4)3F-SO2-4-H2O and Mg2+-H3PO4-H2O systems at high temperature and normal temperature are analyzed.The results show that the equilibrium constant K0 values and pH0 values decrease with increasing temperature in aqueous solution and sulfuric acid solution respectively.That is to say,digesting reactions would proceeding in higher acid value and have large change at high temperature compared to at normal temperature.更多还原