磷化工副产物磷铁加钴真空制备一磷化钴的热力学研究

Thermodynamic Study on Preparation of CoP from Ferrophosphorus By-Product of Phosphorus Chemical Industry

应用“物质吉布斯自由能法”对磷化工副产物磷铁(FeP,Fe2P)为磷源加钴制备一磷化钴的热力学进行了理论计算。结果表明:在(298~1500)K,FeP,Fe2P与Co反应的吉布斯自由能ΔGT分别由-20.265kJ·mol^-1变化到-75.444kJ·mol^-1,13.149kJ·mol^-1变化到-54.889kJ·mol^-1;FeP与Co制备CoP反应的最低温度为-133K,自由能与温度的关系式为ΔGT=-0.0462T-6.1592,其平衡常数与温度的关系式lgKθ=0.33891T+0.0024;Fe2P与Co制备CoP反应的最低温度566K,反应的自由能与温度的关系式ΔGT=-0.0558T+31.5781,其平衡常数与温度的关系式lgKθ=-1.53461T+0.0028。计算结果为真空实制备验研究提供了热力学依据,同时为磷铁的循环利用制备过渡金属磷化物提出了新思路。

The"Gibbs free energy method"was used to study the thermodynamics of preparation CoP by Fe2P or FeP and Co.The Gibbs free energy of the reactions varied from-20.265 kJ·mol^-1 to-75.444 kJ·mol^-1,and from 13.149 kJ·mol^-1 to-54.889 kJ·mol^-1,respectively,when the temperature is in the range of 298 K to 1500 K.It is possible to prepare CoP in the calculated temperature range.The relationships were obtained of the Gibbs free energy and the equilibrium constant with temperature of preparation of CoP by Fe2P and FeP added Co.They wereΔGT=-0.0462T-6.1592,andΔGT=-0.0558T+31.5781,lgKθ=0.33891T+0.0024,lgKθ=-1.53461T+0.0028 of reaction of(1)and(2),respectively,under the same temperature range.The minimum temperature is-133 K and 566 K of the preparation reaction of CoP by FeP,Fe2P and Co,respectively.It provides thermodynamic parameters for experimental study.