| Summary: | 碩士 === 國立成功大學 === 化學工程學系 === 86 === Abstract The applications of surface acting components on
industrial processesare very widely , which includes
exploitation and transportation of petroleum ,catalysis reaction
by PTC , dyeing of fabric , manufacture ofdetergents and
cosmetics , etc. . While under some conditions , twoimmicible
liquid phases in the processes will undergo phase change, i. e.
atransformation between the continuous and dispersed phase.
Bothadsorption on interface and micelle formation of surfactant
molecules resultin emulsification , dispersion , foaming ,
suspension , etc. . Therefore theeffects of surfactants upon
the phase inversion phonomena ofliquid-liquid systems is always
a primary concern in chemical engineering. In this study ,
we intended to investigate the phase inversioncharacteristics of
the water/n-Hexane systems containing ionic surfactantssuch as
DTMAC , CTAB , SDS and Na-oleate. In the systems
withoutmicelles formed , it was found that , adding ionic
surfactant makes watereasier to become the continuous phase and
levels up the hysteresis region.Phase inversion from W/O to O/W
will happen easily. However , thebreadth of the hysteresis
region would become larger by increasing thesurfactant
concentration. This will retard the happening of phase
inversionfrom W/O to O/W. In the systems with micelles formed ,
solubilizationof micelles results in the change of phase
inversion mechanisms. It wasfound that , the higher the
surfactant concentration , the larger thebreadth of the
hysteresis region. By the way , the structure of micelles , HLB
of surfactants and polarity of the organic phase also
affectphase inversion hold-ups of the systems. Generally
speaking , adding nonionic surfactant Tween 20 results
instabilizing the electric double-layers of the dispersed phase.
Addingelectrolytes like and also results in increasing
theelectric double-layers of the dispersed phase. Both of them
alleviatedthe effects of the concentrations of ionic surfactants
upon the phaseinversion characteristics.
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