Premix membrane emulsification

High Throughput Production of Double Emulsions using Packed Bed Premix Emulsification

Wed, 2015-02-18 11:07 — Hassan Ismaiel Sawalha (Manasra)

Journal Title, Volume, Page:

Food Research International Volume 66, Pages 78–85

Year of Publication:

2014

Link:

http://www.sciencedirect.com/science/article/pii/S0963996914005638

Authors:

Hassan Sawalha

An-Najah National University, Chemical Engineering Department, Nablus, Palestine

Current Affiliation:

Department of Chemical Engineering, An-Najah National University, Nablus, Palestine

[email protected]

Sami Sahin

Wageningen University, Food Process Engineering Group, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands

Karin Schroën

Wageningen University, Food Process Engineering Group, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands

Preferred Abstract (Original):

We explored the potential of packed bed premix emulsification for homogenizing coarse food grade W/O/W emulsions, prepared with sunflower oil. Using packed beds with different glass bead sizes (30–90 μm) at different applied pressures (200–600 kPa), emulsions with reasonably uniform droplet size (span ~ 0.75) were produced successfully at high fluxes (100–800 m³ m^− 2 h^− 1). Sodium chloride was used as a release marker: after five homogenization cycles, the produced emulsions were found to retain almost all of their initial content (99%). As was previously found for single emulsions, the packed bed system proved to be effective in breaking up the W/O/W emulsion droplets, with droplet to pore size ratios as low as 0.3. Results were analysed through the pore Reynolds number, Re_p, which characterizes the flow inside the packed bed, and were related back to the droplet break-up mechanisms occurring. At high Re_p, droplet break-up was expected to be governed by shear forces while at low Re_p, there is a shift from shear based to spontaneous droplet break-up.

Preparation of hollow polylactide microcapsules through premix membrane emulsification-Effects of nonsolvent properties

Thu, 2013-02-14 14:24 — Hassan Ismaiel Sawalha (Manasra)

Journal Title, Volume, Page:

Journal of membrane science, 325(2): p. 665-671

Year of Publication:

2008

Authors:

Hassan Sawalha

Food and Bioprocess Engineering Group, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands

Current Affiliation:

Chemical Engineering Department, An-Najah National University, Nablus, Palestine

[email protected]

Yuxuan Fan

Food and Bioprocess Engineering Group, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands

Karin Schroën

Food and Bioprocess Engineering Group, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands

Remko Boom

Food and Bioprocess Engineering Group, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands

Preferred Abstract (Original):

Hollow polylactide microcapsules that can be used as ultrasound contrast agents were prepared using premix membrane emulsification. Polylactide/dichloromethane and dodecane solutions were emulsified together with a nonsolvent phase (water or a water–alcohol mixture) by repeated passage through a glass fibre membrane. The solvent, dichloromethane, diffuses out of the droplets and the polylactide solidifies around a droplet of dodecane. To investigate the effect of the nonsolvent properties on the size and span of the microcapsules, different methanol–water, ethanol–water and 2-propanol–water mixtures were used as nonsolvents. The alcohol lowers the interfacial tension and increases the viscosity of the nonsolvent, and therewith it decreases the size and the span of the microcapsules. It was remarkable that 2-propanol yields the smallest size (0.35 μm) followed by ethanol (0.8 μm) and methanol (1.4 μm). In contrast, the smallest span was obtained with methanol (0.7), whereas 2-propanol gave the largest span (1.5). The results further show that the size and the span of the microcapsules decreases with increasing number of emulsification passes and transmembrane flux. The presence of alcohol in the nonsolvent phase increases the efficiency of the emulsification process and decreases the optimum number of passes required to obtain the minimum average size of the droplets. A three-parameter correlation was defined that could quantitatively describe the effects of all the aforementioned parameters on the size of the microcapsules.

An-Najah Staff