Size control of nanobubbles generated from Shirasu-porous-glass (SPG) membranes

✍ Scribed by Masato Kukizaki; Masahiro Goto

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 670 KB
• Volume: 281
• Category: Article
• ISSN: 0376-7388
• DOI: 10.1016/j.memsci.2006.04.007

✦ Synopsis

We recently discovered that monodispersed nanobubbles/microbubbles could be generated from Shirasu-porous-glass (SPG) membranes with uniform pores in a system composed of dispersed gaseous and continuous water phases containing a surfactant. In the present study, size control of the nanobubbles generated was examined using SPG membranes with less than submicron-size pores. Air was pressurized into a sodium dodecyl sulfate (SDS) solution ranging from 0.05 to 0.5 wt.% flowing through a SPG membrane with a transmembrane/bubble point pressure ratio of 1.1-2.0. Under these conditions, monodispersed nanobubbles with a mean bubble diameter of 360-720 nm were stably produced from membranes with mean pore diameters of 43-85 nm. The mean bubble diameter was shown to be 8.6 times larger than the mean pore diameter; therefore, the nanobubble diameter could be controlled by the membrane pore size. Mean bubble diameter was barely affected by a flow velocity of 0.5-3.7 m s -1 or by the surface tension between air and 0.05-0.5 wt.% SDS solution.