采用水热法合成单相La2(CO3)3·3.4H2O。采用XRD、FTIR以及DTA-TG对La2(CO3)3·3.4H2O在30~1000°C的热分解过程、中间及最终产物进行表征。在非等温条件下对La2(CO3)3·3.4H2O在30~366°C范围内的热脱水动力学进行研究。采用Flynn-Wall-Ozawa及Friedman 等转化法计算其反应活化能并对其反应阶段进行分析。采用多元非线性回归程序确定其最可能的反应机理及动力学参数。结果表明，La2(CO3)3·3.4H2O 的热脱水为三步竞争反应，一个 n 序列初始反应后为 n 序列竞争反应(FnFnFn 机理)。经最可能的反应机理计算所得的活化能与Friedman等转化法的计算结果非常接近，拟合后的TG及 DTG曲线与原始曲线能较好地吻合。%The single phase La2(CO3)3·3.4H2O was synthesized by hydrothermal method. The thermal decomposition and intermediates and final solid products of La2(CO3)3·3.4H2O from 30 to 1000 °C were characterized by XRD, FTIR and DTA-TG. The kinetics of dehydration of La2(CO3)3·3.4H2O in the temperature range of 30-366 °C was investigated under non-isothermal conditions. Flynn-Wall-Ozawa and Friedman isoconversion methods were used to calculate the activation energy and analyze the reaction steps; multivariate non-linear regression program was applied to determine the most probable mechanism and the kinetic parameters. The results show that the thermal dehydration of La2(CO3)3·3.4H2O is a kind of three-step competitive reaction, and controlled by ann-order initial reaction followed byn-order competitive reaction (FnFnFnmodel). The activation energy matching with the most probable model is close to value obtained by Friedman method. The fitting curves match the original TG-DTG curves very well.
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