Membrane Engineering Lab @ CYCU

Membranes are dense or porous polymeric, ceramic, metallic or composite interfaces whose function is to separate solutes. Their development and the assessment of their performances require knowledge in multiple fields including materials science, environmental engineering, chemical engineering, biomedical engineering, etc. depending also on the field of application. They have been around for many decades, yet fortunately, hold many secrets. I voluntarily used the word "fortunately" because these secrets justify the time and efforts put by numerous teams worldwide to engineer better membranes for more efficient processes and hopefully, a more sustainable environment.

Our team forming the Membrane Engineering Lab is trying to contribute to these efforts and this page aims to showcase our current themes of research. More particularly, the emphasis is put on the following aspects, all concerning polymeric or composite membranes:

1. Membrane formation mechanisms: we place great importance on understanding and controlling the mechanisms that influence the morphology of membranes. The membrane morphology, such as cellular, bicontinuous, nodular, with or without "fingers," directly impacts their range of applications. We design all our membranes from scratch, mostly by phase-inversion processes and electrospinning, and also utilize commercial membranes as control samples during performance tests. As such, important formulation and process parameters influencing the porous structures are carefully studied during the fabrication of new membranes.

2. The VIPS process, VIPS membranes, and their wide-range of application: VIPS stands for Vapor-Induced Phase Separation, a process that facilitates slow mass transfers. This unique characteristic allows for precise control over membrane structures. Among the various formation routes we explore for preparing membranes, we dedicate significant efforts to the development of VIPS membranes. We look into the wide yet poorly explored range of applications of these membranes. It includes:

   1. 1. • • the bacterial removal from water by pressure-driven microfiltration-type process,

           • the gravity-driven breaking of emulsions,

           • the desalination and removal of micropollutants by direct contact membrane desalination, with an emphasis on reaching high flux and rejection under both low feed temperature and low feed-permeate temperature gradient.

For scalability, we are trying to develop these membranes in one step, and commercially available polymers. To improve some properties, we sometimes utilize nanoparticles in blend with the matrix polymer, prior to membrane fabrication.

3. The fabrication of antifouling and green membranes: since fouling, which refers to the attachment of particles, proteins, cells, and so on, is an inevitable consequence of membrane separation, we are currently designing materials and membranes that can resist irreversible fouling. The objective is to prolong the lifetime of the membranes and reduce overall process costs. Furthermore, we are focusing our efforts on developing green membranes, which are fabricated using environmentally friendly solvents.

4. Membranes for advanced applications: We impart specific functional properties to some of our membranes. For instance, we are developing "killer membranes" that can kill bacteria during separation, catalytic membranes able to degrade solutes (such as antibiotics) during the separation, or smart membranes that can selectively catch cells during blood filtration. The fabrication of these membranes often involves at least 2 steps during the fabrication.  Classically, we first prepare the main polymeric matrix before imparting functional properties via a surface modification approach (plasma -treatment, spray-coating, etc...)