CaO和Ca（OH）2脱硫反应的热力学分析及机理研究

运用化学热力学理论对钙基脱硫剂CaO和Ca（OH）2的脱硫反应的吉布斯函数（△G），反应平衡常数，平衡时SO2的分压进行计算，从而得出脱硫反应AG—T的关系式，计算不同温度下的AG，进而分析反应发生的可能性。在实验室条件下，CaO有效反应温度800℃下进行干法脱硫，Ca（OH）2反应温度60℃湿法脱硫，分别在Ca／S摩尔比为1．0、1．5和2．0进行实验。结果表明：CaO和Ca（OH）2脱硫剂脱硫活性为：Ca（OH）2大于CaO。这与热力学计算结果相一致，并且从反应机理出发，分析了脱硫活性差异的原因。

Study on Thermodynamic Analysis and Mechanism of Desulphurization Reactions for CaO and Ca(OH)_2 Desulphurization Agents

The function relationship between AG（ Gibbs free energy of formation） and T was deduced by calculating AG, Kp （ equilibrium constant in pressure） of calcium - based desulphurization agents （ CaO and Ca （OH） 2 ） desulphurization reactions and partial pressure at equilibrium state of them utilizing the theory of chemical thermodynamics. From calculating AG at different temperature, the denotation of AG and the possibility of the desulphurization function was analyzed further. The experiments were conducted at 800℃（for CaO in dry desulphurization reaction） and 60℃ （for Ca（OH）2 in wet desulphurization reaction）, at the Ca/S molar ratio of 1. 0, 1. 5 and 2.0. The results indicated the sequence of the SO2 removal activity was Ca（ OH）2 〉 CaO. It was the same as the results of calculation by the method of thermodynamics. From the reaction mechanism, the reason for the differences of SO2 being removed activity was deduced.