کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
620790 882512 2011 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Coalescence of bubbles and stability of foams in aqueous solutions of Tween surfactants
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی تصفیه و جداسازی
پیش نمایش صفحه اول مقاله
Coalescence of bubbles and stability of foams in aqueous solutions of Tween surfactants
چکیده انگلیسی

Coalescence of air bubbles and stability of foams in aqueous solutions of Tween 20, 40, 60 and 80 are reported in this work. Adsorption of the surfactants at air–water interface was studied by measuring the surface tension of the surfactant solutions. The surface tension profiles were fitted using a surface equation of state derived from the Gibbs and Langmuir adsorption equations. The critical micelle concentration and surface tension at this concentration were determined. The effect of surfactant concentration on coalescence of air bubbles at flat air–water interface was studied. The role of steric force on coalescence time was investigated. The coalescence time distributions were fitted by the stochastic model. The mean values of the distributions were compared with the predictions of seven film-drainage models. Stability of foams was analyzed by the Ross–Miles test. The initial and residual foam heights were measured at different surfactant concentrations. The stability of foams was compared with the coalescence time of the bubbles.


► Coalescence of bubbles and stability of foams were studied.
► Results were analyzed by film-drainage and stochastic theories.
► Adsorption of surfactants depends on their structure.
► Bubble coalescence time and foam stability increase with surfactant concentration.
► Foam stability can be predicted from the stability of a single bubble.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemical Engineering Research and Design - Volume 89, Issue 11, November 2011, Pages 2344–2355
نویسندگان
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