多元组分盐溶液蒸发动力学和最终粒子形态学滴滴
Barnaby E A Miles1, Emily Winter1, Shaira Mirembe1
1School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.
The journal of physical chemistry. A
|January 11, 2025
概括
混合盐气溶的干燥动力学取决于成分,影响粒子形态. 这项研究探讨了不同的盐混合物如何影响蒸发过程中的干燥颗粒结构和均性.
科学领域:
- 大气化学 大气化学
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 含有多种无机溶液的气溶滴在自然界和工业中很常见.
- 了解它们的干燥动力学和由此产生的粒子形态对于药物输送,疾病传播缓解和气候建模等应用至关重要.
- 之前的研究主要集中在单元气溶上,对混合盐系统的知识存在差距.
研究的目的:
- 为了研究混合盐水性气溶滴的干燥动力学 (NaCl-(NH4) 2SO4,NaCl-NH4NO3,NaCl-CaCl2).
- 确定干燥动力学对所产生的干燥微粒的形态和组成的影响.
- 建立混合盐成分,干燥行为和最终颗粒特征之间的关系.
主要方法:
- 使用比较动力学电动平衡来测量混合盐气溶在一系列相对湿度 (0-50% RH) 的蒸发概况.
- 在受控的RH条件下使用下降滴柱来干燥混合盐滴的种群.
- 分析了使用扫描电子显微镜 (SEM) 的粒子形态和使用能量分散光谱 (EDS) 进行原子映射的组成.
主要成果:
- 蒸发动力学测量与"单个气溶干燥动力学和轨迹"模型一致.
- 在混合盐滴中,干燥动力学和粒子形态学之间的关系被发现是组成上依赖的.
- 粒子形态和微观结构的均性是由主要的结晶盐 (例如 (NH4) 2SO4,Na2SO4,NaCl) 确定,并受干燥速度的影响.
结论:
- 混合盐气溶的干燥动力学和由此产生的颗粒形态学强烈取决于它们的特定盐成分.
- 主导盐的结晶行为决定了最终的粒子结构.
- 干燥速度显著影响干燥颗粒的微观结构中的组成均性.
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