Geometric parameters influencing production of O/W emulsions using flat metallic membranes and scale-up

• Published in: Journal of membrane science Vol. 430; pp. 140 - 149
• Main Authors: Suárez, Miguel A., Gutiérrez, Gemma, Coca, José, Pazos, Carmen
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-03-2013; Elsevier
• Subjects: artificial membranes; Chemistry; Colloidal state and disperse state; droplet size; emulsifying; emulsions; Emulsions. Microemulsions. Foams; Exact sciences and technology; Flat metallic membrane; General and physical chemistry; Geometric parameters; Membrane emulsification; Membranes; Scale-up; Stirred tank; tanks; Stirred tank; Geometric parameters; Flat metallic membrane; Membrane emulsification; Scale-up; Water; Speed; Oil water emulsion; Droplet; Continuous phase; Membrane separation; Pore size; Oil; Membrane; Membrane pore
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2012.12.013

The influence of geometric parameters (e.g., tank dimensions, diameter and position of impeller, continuous phase height-to-tank diameter ratio and impeller-to-tank diameter ratio) on the droplet size of emulsions produced by membrane emulsification has been studied. Two flat metallic membranes with pore sizes of 5μm and 50μm were used to prepare oil-in-water (O/W) emulsions in stirred tanks. Results show that the influence of geometric parameters depends on the rotational speed of the impeller. Under optimal geometric conditions, it was possible to obtain emulsions with minimum droplet sizes of 45μm and 105μm and span values of 0.60 and 0.53 using membranes with pore sizes of 5μm and 50μm, respectively. Scale-up experiments were carried out with different tanks and impellers, while maintaining geometric similarity. Emulsions with the same droplet size distributions were obtained using the impeller tip speed as the scale-up criterion.
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► Impeller design and liquid height have important influence on droplet size. ► The optimal ratio between the continuous phase height and the tank diameter is equal to 1.0. ► Baffles do not improve membrane emulsification performance. ► Impeller tip speed is the scale-up parameter in stirred tank membrane emulsification.