CIESC Journal ›› 2020, Vol. 71 ›› Issue (9): 4161-4167.DOI: 10.11949/0438-1157.20200477

• Fluid dynamics and transport phenomena • Previous Articles     Next Articles

Experimental study on effect of alcohol surfactants on bubble coalescence in full range of concentrations

Huahai ZHANG(),Yuelin WANG,Tiefeng WANG()   

  1. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • Received:2020-05-03 Revised:2020-06-10 Online:2020-09-05 Published:2020-09-05
  • Contact: Tiefeng WANG

全浓度范围下醇类表面活性剂对气泡聚并影响的实验研究

张华海(),王悦琳,王铁峰()   

  1. 清华大学化学工程系,北京 100084
  • 通讯作者: 王铁峰
  • 作者简介:张华海(1995—),男,博士研究生,950826zhh@sina.com
  • 基金资助:
    国家重点研发计划项目(2017YFB0602500)

Abstract:

By experimentally measuring the bubble coalescence time of different alcohol surfactants in the full concentration range, the effects of surfactant types and their concentrations on bubble coalescence were studied. The results showed that the addition of alcohol surfactant remarkably inhibited the bubble coalescence, resulting in more stable liquid film and longer bubble coalescence time. With increasing alcohol concentration, the bubble coalescence time increased significantly in the low concentration range, but decreased in the high concentration range. The inhibition of bubble coalescence by alcohol surfactant had a critical concentration. The critical molar fraction corresponding to maximum inhibition on bubble coalescence were 0.0030 and 0.0096 for isopropanol and ethanol, respectively. In addition, by comparing the inhibition effects of different alcohols, the results show that the long-chain alcohols have stronger inhibition on bubble coalescence due to their stronger steric force. Finally, according to the Andrew model analysis, the surface tension gradient is one of the main factors that reflect the ability of the surfactant to inhibit bubble coalescence.

Key words: alcohol surfactant, full concentration range, bubble coalescence, inhibition, surface tension gradient

摘要:

通过实验测量不同醇类表面活性剂在全浓度范围下的气泡聚并时间,进而研究表面活性剂种类及其浓度对气泡聚并的影响。结果表明,加入醇类表面活性剂后,相比于纯液体体系,气泡聚并受到明显抑制,液膜更加稳定,气泡聚并时间延长。低浓度范围内,气泡聚并时间随着表面活性剂浓度的升高显著增长,而在高浓度范围内,气泡聚并时间随着浓度的升高显著缩短。醇类表面活性剂对气泡聚并的抑制作用存在临界浓度。实验测得异丙醇和乙醇对气泡聚并抑制作用最强时对应的临界摩尔分数,分别为0.0030和0.0096。此外,对比不同醇对气泡聚并的抑制作用,发现长碳链醇由于更强空间力而具有更强的抑制气泡聚并能力。最后根据Andrew模型分析表明,表面张力梯度是体现表面活性剂抑制气泡聚并能力的主要因素之一。

关键词: 醇类表面活性剂, 全浓度范围, 气泡聚并, 抑制, 表面张力梯度

CLC Number: