硫酸盐的独立于大小的核和生长模型,来自通过结晶生成的超和溶液
1Department of Chemical Engineering, Sichuan University of Science & Engineering, Zigong 643000, China.
Molecules (Basel, Switzerland)
|January 11, 2024
概括
这项研究详细介绍了硫酸盐在床中的结晶动力学. 高温和超和降低了诱导时间和关键核化参数,提高了核化速率和粒子大小.
科学领域:
- 化学工程是化学工程的重要组成部分.
- 结晶科学 结晶科学
- 物理化学 物理化学
背景情况:
- 了解结晶动力学对于优化工业流程至关重要.
- 硫酸结晶在各种化学应用中至关重要.
- 经典核化理论为研究结晶机制提供了一个框架.
研究的目的:
- 实验性地研究硫酸结晶的动力学.
- 用古典核化理论在不同条件下确定核化参数.
- 在系统中开发晶体核和生长的动力方程.
主要方法:
- 在床中对硫酸结晶的实验研究.
- 应用经典核化理论来分析同质和异质核化.
- 感应时间和关键核化参数 (表面张力,半径,自由能量,分子数) 的确定.
- 使用人口平衡方程拟合动力方程.
主要成果:
- 温度升高和超和降低了诱导时间,关键核化自由能量,半径和分子数量,同时增加了核化速率.
- 晶体形状基本上不受影响,但粒子大小 (D10,D50,D90) 随着超和和温度的增加而增加.
- 晶体生长率随着超和速率的增加而增加.
- 悬浮密度对核化速率的影响最大,其次是超和率和速率.
结论:
- 实验结果与经典核化理论的预测一致.
- 通过使用人口平衡模型,成功地将核形成和生长的动力方程配合起来.
- 研究结果为优化工业硫酸结晶过程和结晶器设计提供了理论指导.
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