CAJ | 학술논문

以PEG 20000为表面活性剂在撞击流反应器中制备La2O3超细粉体的前驱体十水草酸镧(La2(C2O4)3· 10H2O).在室温至900℃下研究La2(C2O4)3·10H2O的热分解过程,通过FTIR和DSC-TG对其反应中间物及最终固体产物进行分析.结果表明,该热分解过程由5个连续的反应阶段组成.采用Flynn-Wall-Ozawa(FWO)和Kissinger- Akahira-Sunose (KAS)法对活化能E进行求取,结果显示E值随着α的变化而变化,说明草酸镧的分解为复杂的热分解过程.采用多元非线性回归分析法对动力学方程和相关动力学参数进行拟合,得到动力学模型为G(α)=[1-(1+α)1/3]2.采用该动力学模型求得的活化能平均值与采用FWO法和KAS法计算而得的活化能平均值十分接近,其拟合曲线与样品的热重分析曲线吻合.
이PEG 20000위표면활성제재당격류반응기중제비La2O3초세분체적전구체십수초산란(La2(C2O4)3· 10H2O).재실온지900℃하연구La2(C2O4)3·10H2O적열분해과정,통과FTIR화DSC-TG대기반응중간물급최종고체산물진행분석.결과표명,해열분해과정유5개련속적반응계단조성.채용Flynn-Wall-Ozawa(FWO)화Kissinger- Akahira-Sunose (KAS)법대활화능E진행구취,결과현시E치수착α적변화이변화,설명초산란적분해위복잡적열분해과정.채용다원비선성회귀분석법대동역학방정화상관동역학삼수진행의합,득도동역학모형위G(α)=[1-(1+α)1/3]2.채용해동역학모형구득적활화능평균치여채용FWO법화KAS법계산이득적활화능평균치십분접근,기의합곡선여양품적열중분석곡선문합.
Lanthanum oxalate hydrate La2(C2O4)3·10H2O,the precursor of La2O3 ultrafine powders,was prepared by impinging stream reactor method with PEG 20000 as surfactant.Thermal decomposition of La2(C2O4)3·10H2O from room temperature to 900 ℃ was investigated and intermediates and final solid products were characterized by FTIR and DSC-TG Results show that the thermal decomposition process consists of five consecutive stage reactions.Flynn-Wall-Ozawa (FWO) and Kissinger-AkahiraSunose (KAS) methods were implemented for the calculation of energy of activation (E),and the results show that E depends on α,demonstrating that the decomposition reaction process of the lanthanum oxalate is of a complex kinetic mechanism.The most probable mechanistic function,G(α)=[1-( 1+α)1/3]2,and the kinetic parameters were obtained by multivariate non-linear regression analysis method.The average E-value that is compatible with the kinetic model is close to value which was obtained by FWO and KAS methods.The fitting curve matches the original TG curve very well.