摘要
采用水热法合成了Zr W2O8的前驱体Zr W2O7(OH)2(H2O)2,并应用热重分析技术研究了其脱水反应。升温速率β=10℃/min,实验失重率为8.382%,与理论失重率8.452%基本吻合,脱水反应温度在173℃左右。应用非等温方法计算了钨酸锆前驱体脱水反应的动力学参数:表观活化能E=232.54 k J/mol;阿伦尼乌斯指前因子ln A=58.06。前驱体脱水为二级反应,动力学方程可以描述为:dα/dt=1025.21exp(-27.97×103/T)(1-α)2。
Zr W2O7（ OH）2（ H2O）2was synthesized by hydrothermal method,which is a precursor for synthesis of zirconium tung state（ Zr W2O8）,and the dehydration reaction in nitrogen atmosphere was investigated via thermogravimetry（ TG） and derivative thermogravimetry（ DTG）. The β of heating rate was 10 ℃ / min,the mass loss occurred at temperatures 173 ℃,and the mass loss was 8. 541%,which was agreement with the theoretical value of 8. 452%. Employing non-isothermal method,the kinetic parameters for dehydration reaction were evaluated. The results showed that apparent activation energy（ E） and pre-exponential factor ln A of the dehydration reaction are 232. 54 k J / mol and 58. 06,respectively. The kinetic equation of dehydration reaction for the precursor could be expressed as： dα / dt = 10^25. 21exp（- 27. 97 × 10^3/ T）（ 1- α）^2.
出处
《化学试剂》
CAS
北大核心
2015年第1期18-20,75,共4页
Chemical Reagents
基金
国家自然科学基金资助项目(21206026)
河北省自然科学基金资助项目(B2012402011)
河北省科技厅计划项目(09965117D)
邯郸市科技计划资助项目(1323-108088-13)
关键词
钨酸锆前驱体
脱水反应
动力学
热重分析
Zr W2O7（OH）2（H2O）2Zr W2O8
dehydration reaction
dynamic
TG-DTG
