中文摘要：

利用最新热力学数据及KAlSi3O8—SiO2、CaO—Al2O3-SiO2、K2O—Al2O3-SiO2体系相图，对钾长石分别添加CaO和CaO＋CaSO4的热分解进行了热力学分析，并拟定了可能的反应，在1100～1500K范围内计算了各反应的△GT^0，确定了钾长石添加CaO＋CaSO4制取K2SO4的物料配比范围，并得到了试验验证。

英文摘要：

A thermodynamic analysis is made of the thermal decomposition of potassium-feldspar with the addition of CaO, or CaO ＋ CaSO4, making use of the latest thermodynamic data and phase diagrams of KAISi3Os - SiO2, CaO - Al2O3 - SiO2 and K2O - Al2O3 - SiO2 systems, and possible reactions are worked out. The △GT^0 of each reaction is calculated in the range of 1100 - 1500 K, and the material proportioning range for the addition of CaO ＋ CaSO4 in the production of K2SO4 is established, which is verified by experiments.