Abstract Current studies describe the application of simultaneous TG–DTA–FTIR techniques in the in-situ synthesis of potassium carbonate (K2CO3) from the thermal decomposition of potassium tetraoxalate dihydrate [KH3(C2O4)2.2H2O]. Progress of the decomposition reactions with increasing temperatures was monitored online through TG mass loss, corresponding heat effects and evolved gases. Sequential formation of anhydrous potassium tetraoxalate, potassium hydrogen oxalate [KHC2O4] and potassium oxalate [K2C2O4] was confirmed using thermal, ATR − FTIR and PXRD measurements. The intermediate potassium oxalate undergoes structural transformation and then decomposes to potassium carbonate by the temperature of 600 °C. PXRD measurements confirm the formation of K2CO3 and the results are in agreement with ATR − FTIR and thermal analysis.

中文翻译：

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四草酸钾原位合成碳酸钾中间产物表征及热分解机理

摘要 目前的研究描述了同步 TG-DTA-FTIR 技术在由二水合四草酸钾 [KH3(C2O4)2.2H2O] 的热分解原位合成碳酸钾 (K2CO3) 中的应用。通过 TG 质量损失、相应的热效应和放出的气体在线监测随着温度升高分解反应的进程。使用热、ATR - FTIR 和 PXRD 测量证实了无水四草酸钾、草酸氢钾 [KHC2O4] 和草酸钾 [K2C2O4] 的连续形成。中间体草酸钾发生结构转变，然后在600℃的温度下分解为碳酸钾。PXRD 测量证实了 K2CO3 的形成，结果与 ATR - FTIR 和热分析一致。