CO2 capture and utilization
Following the principle of membrane deployment for a more sustainable society, our lab has joined the global effort to address climate change. So far, the work has been focused on carbon capture and its valorization in the form of bicarbonate salts and/or organic molecules. First, carbon capture is performed by absorbing CO2 in a gas-liquid membrane contactor set-up. Greener solvents are of interest for the absorption, although they are often kinetically limited. Current work addresses the enhancement of the absorption by promoting the solvents with amino acids or enzymes (either dissolved in the solvent or immobilized on the membrane surface). Envisaging a more realistic study of the process performance, the effect of SO2 and NOX in the effluent gas to be treated by the membrane contactor is also considered. After the absorption step, the bicarbonate salts must be separated from the homogenous catalysts, i.e. dissolved enzymes or amino acids, either by ultrafiltration or nanofiltration processes. This allows the reutilization of the catalysts. In the case of enzyme immobilized on the membrane surface, this step can be avoided. The final product is obtained after concentration and crystallization of the aqueous bicarbonate solution using membrane crystallization (OMD, DCMD or VMD).
Researchers: Kamyll Dawn Cocon, Ysaline Toussaint
Senior scientists / postdoc researchers: Dr. Mar Garcia Alvarez
Alumni: Dr. Yusak Hartanto, Dr. Marie-Charlotte Sparenberg, Dr. Christhian Molina Fernandez, Dr. Vida Sangsefidi; Dr. Ruiz Salmon Israel
Membrane processes for water treatment
Pressure-driven membrane processes, such as nanofiltration (NF) and reverse osmosis (RO) hold great promise for heavy metal removal due to their ease of use, small footprint and high efficiency. Nanofiltration is a membrane-based process used to remove metals from wastewater and colloidal materials, operating at low transmembrane pressures. Recently, RO membranes operating at ultra-low pressures, similar to nanofiltration have been developed. In this research line, our work focuses on the elimination of micro-pollutants from household and industrial effluents to WHO standards and the permeate can be reused. Furthermore, a hybrid process of RO or NF coupled with membrane crystallization (MCr) is being investigated to recover useful compounds from the retentate. Finally, anti-biofouling nanofiltration membrane separator in microbial fuel cells (MFCs) is also being explored to treat textile wastewater.
Researchers: Wuhib Zeine Ousman; Shuangling Xie
Alumni: Dr. Vercus Lumami Kapepula; Dr. Raul Bahamonde Soria; Dr. Raphaël Janssens
Membrane synthesis
Different applications require distinct membrane properties. In our laboratory, some processes utilize commercial membranes but some lines of research investigate the preparation of novel membranes with the desirable characteristics. Some examples are given below.
- Biocatalytic composite membranes for gas-liquid membrane contactors
Gas-liquid membrane contactor is one of the promising membrane separation technologies for carbon dioxide capture. When greener solvents are used, the carbon capture efficiency decreases significantly due to the slower kinetics of these greener solvents. Combining biocatalysts or enzymes with these green solvents could boost the carbon capture efficiency while allowing for conversion of capture carbon dioxide into useful products. In this research line, we are developing immobilization platform for biocatalysts or enzymes on the membrane surface by exploring the functionalities of : (1) biopolymers and metal-organic frameworks and (2) (poly) ionic liquids.
- Composite and mixed matrix membranes for pervaporation/reactive pervaporation and water purification
- Porous membranes for membrane crystallization
Crystal shape and size can impact drug properties like flowability, compatibility, dissolution, and absorption rate in the blood steam. To fine-tune crystal properties, porous membranes are used to control mixing and antisolvent mass transfer in Antisolvent Crystallization. To this end, membranes of various thickness, porosity, surface morphology and hydrophobicity are investigated.
- Supporter ionic liquid membranes for pervaporation/reactive pervaporation and liquid extraction
Tunability of physicochemical properties of ionic liquids makes them very interesting solvents. In supported ionic liquid membranes a small amount is immobilized in the membranes pores. The resulting membranes present high flux and good selectivity towards the target compounds.
Researchers: Kamyll Dawn Cocon; Akshara Iyer; Syeda Laraib
Alumni: Dr. Sara Chergaoui, Dr. Xiao Xu, Dr. Vercus Lumami Kapepula, Dr. Gilles Van Eygen; Dr. Raul Bahamonde Soria
Separation of reaction mixtures
Reactive pervaporation. The research is a hybrid process of combined transesterification reaction and pervaporation in one setup, which contains three steps: (1) development of methanol (MeOH)-selective pervaporative membranes, (2) utilization of the developed MeOH-selective membranes in reactive pervaporation setup, and (3) development of catalytic and MeOH-selective membranes.
Researchers: Akshara Iyer
Alumni: Dr. Xiao Xu, Dr. Gilles Van Eygen; Dr. Daria Nikolaeva; Dr. Wenqi Li
Membrane crystallisation
Two distinct techniques of membrane crystallization are under study in the lab, namely membrane distillation-crystallization and membrane-assisted anti-solvent crystallization (MAAC). Membrane distillation-crystallization takes advantage of the membrane that can allow a non-dispersive contact between two streams, which leads to the progressive distillation of the feed stream and eventually provokes crystallization of the salt. Different configurations are investigated: osmotic, direct contact and vacuum membrane distillation-crystallization.
As for MAAC, it consists of the control of antisolvent mass transfer through the membrane pores to the crystallizing solution resulting in specific crystal properties such as crystal shape/ morphology, crystallinity, polymorphism, etc., plus a narrow crystal size distribution which is desirable particularly in the production of pharmaceutical or agrochemical products. Studies in this area cover the impact of the operating conditions (flow rate, temperature, pressure, solution composition, etc.) and the membrane properties (porosity, thickness, hydrophobicity, etc.).
Researchers: Syeda Laraib ; Wuhib Zeine Ousman
Senior scientists / postdoc researchers: Dr. Mar Garcia Alvarez
Alumni: Dr. Sara Chergaoui, Dr. Marie-Charlotte Sparenberg ; Dr. Vida Sangsefidi
Life Cycle Assessment
As sustainability is in the center of our preoccupations, a line of research is dedicated to the quantification of the environmental impacts related to the life cycle of products or services. Indeed, LCA is a useful tool to verify that our efforts to reduce CO2 emissions don’t lead to other problems such as excessive land use or more frequent acid rains. Our group developed an expertise with SimPro, which has been among the leading LCA software solutions for over 30 years.
Researchers: Ysaline Toussaint
Alumni: Dr. Marie-Charlotte Sparenberg