Reaction Thermodynamics and Kinetics Analysis of Dry Extraction of Ba14CO3 by Irradiated AlN
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摘要: 通过热力学计算软件（HSC）对堆照AlN复杂物系下的一段高温氧化反应及主要反应单元进行了初步的热力学与动力学分析，并进行了实验验证。结果表明：为提高14CO2的产率，需保证反应时O2充足；反应速率由O2的吸附和14CO2的脱附过程的扩散控制；应从改善气-固反应物的反应器选型、接触方式、接触时间、反应温度等方面着手改进工艺从而提高反应速率。本文研究结果为批量化制备高比活度Ba14CO3提供了重要技术支持。Abstract: The reaction thermodynamics, kinetics analysis and demonstration test of a high temperature oxidation reaction under complex irradiated AlN system was carried out by thermodynamic calculation software (HSC). The results show that it is necessary to ensure sufficient O2 during the reaction to improve the yield of 14CO2. The reaction rate is controlled by the diffusion of O2 adsorption and 14CO2 desorption. To improve the reaction rate, the process should be improved from the aspects of reactor selection, contact mode, contact time and reaction temperature of gas-solid reactants. It provides important technical support for batch preparation of high specific activity Ba14CO3.
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Key words:
- Irradiated AlN /
- Dry extraction /
- Ba14CO3 /
- HSC
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图 2 堆照AlN干法提取Ba14CO3实验流程
1—氧气；2—主反应管式氧化炉；3—小管式炉；4—防倒吸瓶；5—洗气瓶；6~8—吸收池
Figure 2. Experimental Process of Dry Extraction of Ba14CO3 by Irradiated AlN
图 3 不同氧气比例下的一段高温气-固反应的平衡组成
Figure 3. Equilibrium Composition of a High Temperature Gas-Solid Reaction at Different Oxygen Ratios
图 4 不同温度下转化率与时间的关系
Figure 4. Relationship between Conversion and Time at Different Temperatures
表 1 验证试验结果
Table 1. Verification Test Results
试验
编号主反应
工艺条件靶料比活度/
(mCi·g−1)AlN
质量/g提取活
度/mCi提取率/
%Ba14CO3/
mgⅠ 反应温度：1000℃
反应时间：4 h0.0888 8.3 0.103 14 60 Ⅱ 反应温度：1250℃
反应时间：4 h2.3600 0.67 1.58 99 Ⅲ 2.3600 3.00 6.90 97 125 
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