化学学报 ›› 2004, Vol. 62 ›› Issue (4): 386-390. 上一篇    下一篇

研究论文

氯化钆与L-酪氨酸和甘氨酸三元固态配合物的热化学及热分解动力学研究

张忠海1,2, 库宗军2, 夏菲1, 刘义1, 李会荣1, 胡艳军1, 赵顺省1, 屈松生1   

  1. 1. 武汉大学化学与分子科学学院, 武汉, 430072;
    2. 孝感学院化学系, 孝感, 432000
  • 投稿日期:2003-04-21 修回日期:2003-10-17 发布日期:2014-01-26
  • 通讯作者: 刘义,E-mail:liuyi@public.wh.hb.cn E-mail:liuyi@public.wh.hb.cn
  • 基金资助:
    教育部高校优秀青年教师教学科研奖励计划资助项目(2001).

Study on Thermochemistry and Thermal Decomposition Kinetics of Ternary Solid-State Complex of Gadolinium Chloride with L-Tyrosine and Glycine

ZHANG Zhong-Hai1,2, KU Zong-Jun2, XIA Fei1, LIU-Yi1, LI Hui-Rong1, HU Yan-Jun1, ZHAO Shun-Sheng1, QU Song-Sheng1   

  1. 1. College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072;
    2. Department of Chemistry, Xiaogan University, Xiaogan 432000
  • Received:2003-04-21 Revised:2003-10-17 Published:2014-01-26

合成表征了氯化钆与L-酪氨酸和甘氨酸形成的三元固态配合物Gd(Tyr)(Gly)3Cl3·3H2O.用具有恒温环境的溶解-反应热量计,测定了配位反应GdCl3·6H2O (s)+Tyr (s)+3Gly (s)=Gd(Tyr)(Gly)3Cl3·3H2O (s)+3H2O (l)在298.15 K时的反应焓为(9.451±0.468) kJ·mol-1.计算得配合物Gd(Tyr)(Gly)3Cl3·3H2O (s)在298.15 K时的标准摩尔生成焓为ΔfHm(○-)=-(4269.7±2.3) kJ·mol-1.并用热分析手段对配合物进行了非等温热分解动力学研究,推断配合物第二步热分解反应机理为二级化学反应,其动力学方程为:dα/dT=(A/β)exp(-E/RT)(1-α)2,求得分解反应的表观活化能为E=215.17 kJ·mol-1,指前因子为1018.71 s-1.

关键词: 稀土配合物, L-酪氨酸, 甘氨酸, 标准生成焓, 热分解动力学

The ternary solid-state complex of gadolinium chloride with L tyrosine and glycine, Gd(Tyr)(Gly)3Cl 3·3H2O, was synthesized and characterized. Using a solution reaction isoperibol calorimeter, the molar enthalpy of reaction for the following reaction: GdCl3·6H2O (s)+Tyr (s)+3Gly (s)=Gd(Tyr)(Gly)3Cl3·3H2O (s)+3H2O (l), was determined to be (9.451±0.468) kJ·mol-1 at 298.15 K. From the above molar enthalpy of reaction and other auxiliary thermodynamic quantities, the standard molar enthalpy of formation of the titled complex at 298.15 K was derived as -(4269.7±2.3) kJ·mol-1. The kinetics of thermal decomposition of the complex was studied by thermal analysis technique under non isothermal condition. The possible reaction mechanism was suggested to be a second order chemical reaction. The kinetic equation may be expressed as: dα/dT=(A/β)exp(-E/RT)(1-α)2. The apparent activation energy and pre exponential factor of the reaction were 215.17 kJ·mol-1 and 1018.71 s-1, respectively.

Key words: complex of rare earth, L-tyrosine, glycine, standard enthalpy of formation, thermal decomposition kinetics