A method for estimating effective coalescence rates during emulsification from oil transfer experiments

• Published in: Journal of colloid and interface science Vol. 374; no. 1; pp. 25 - 33
• Main Authors: HAKANSSON, Andreas, TRAGARDH, Christian, BERGENSTAHL, Björn
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 15.05.2012; Elsevier
• Subjects: Alkanes - chemistry; Annan teknik; Chemistry; Coalescence; Coalescing; Computer Simulation; Emulsification; emulsifiers; emulsifying; Emulsifying Agents - chemistry; Emulsions - chemistry; Engineering and Technology; equations; Estimating; Exact sciences and technology; Food Engineering; General and physical chemistry; High-pressure homogenization; homogenization; Homogenizing; Hydrocarbons, Brominated - chemistry; Indexing in process; Kinetics; Lactoglobulins - chemistry; Livsmedelsteknik; Mathematical analysis; Mathematical models; Models, Chemical; Muramidase - chemistry; oils; Oils - chemistry; Other Engineering and Technologies; Population Balance Equations; seeds; Sodium Dodecyl Sulfate - chemistry; Teknik; Teknik och teknologier; Thermodynamics; Water - chemistry; Population Balance Equations; Coalescence; Emulsification; High-pressure homogenization; Residence time; Equation; Emulsifier; Fragmentation; Drop; High pressure; Oil; Simulation; Models
• ISSN: 0021-9797; 1095-7103; 1095-7103
• DOI: 10.1016/j.jcis.2011.12.079

[Display omitted] ► A method for obtaining coalescence rates during emulsification is developed. ► The method is based on Taisnes oil transfer experiments and a simulation model. ► Taisnes experimental measure is largely independent of fragmentation rate. ► The method gives qualitative scaling of coalescence with operating parameters. ► The method is exemplified with homogenizer pressure and surface load of emulsifier. The Oil Transfer Technique (OTT) was developed by Taisne et al. [1] to measure coalescence during emulsification and has been applied since in several studies. One of the main drawbacks of this technique is that it only gives a qualitative measure of coalescence. This paper proposes a new evaluation method of OTT experimental results for estimating qualitative coalescence rates, e.g. for investigating the scaling of coalescence with emulsification parameters (such as homogenizing pressure, and emulsifier concentration). The method is based on comparison with simulated OTT experiments using bivariate Population Balance Equation models. Simulations have been performed under a wide variety of conditions in order to investigate the influence of assumptions on coalescence and fragmentation kernels. These investigations show that the scaling of coalescence rates could be determined accurately when the scaling of efficient residence time of drops in the active region of homogenization is known. The proposed evaluation method is also exemplified by analyzing OTT data from two previously published studies.