Abstract: Research on decomposing potassium feldspar to extract potassium by calcination with the composite additive made of CaCl2 and NaCl was carried out. The phase analysis of products and decomposition process were studied by means of XRD and TG-DSC. The results show that the composite additive can shorten the time to reach the reaction balance, and obtain higher extraction rate at a lower calcination temperature and shorter calcination time, and the lower the temperature or the shorter the time, the more obvious the effect. The extraction rate of potassium using the composite additive is 93.65%, 22.57% higher than using CaCl2 and 39.56% higher than using NaCl at the conditions of 800℃ and 60 min. When the temperature reaches 700℃, the reaction rate of the system becomes rapidly, and the composite additive can effectively decrease the decomposition temperature. The optimum calcination temperature range is 800~890℃.

Key words: K-feldspar, additive, calcination, extraction rate

摘要： CaCl2和NaCl按一定比例混合作助剂焙烧分解钾长石提钾，对产物的物相组成及分解反应过程进行了研究. 结果表明，混合助剂能缩短分解反应达到平衡的时间，在较低的焙烧温度和较短的焙烧时间下获得较高的提取率，且温度越低或时间越短效果越明显，在焙烧温度800℃、焙烧时间60 min的条件下，混合助剂的钾提取率为93.65%，比CaCl2高22.57%，比NaCl高39.56%. 超过700℃后，体系进入快速反应阶段，混合助剂有效降低了分解反应温度，适宜的焙烧温度为800~890℃.

关键词: 钾长石, 助剂, 焙烧, 提取率