PoSiMem: towards novel ultrathin membranes

PoSiMem is about developing robust, reproducible and easy to scale-up approaches for the production of novel nanofiltration (NF) membranes composed of periodic organosilica networks and hexagonal nanochannels.

In short:

Membrane-based filtration technologies are known for their low-energy consumption, high throughput, and low carbon footprints
PoSiMem aims to develop robust, reproducible and easy to scale-up approaches for the production of novel NF membranes
Low-cost methods and materials will be investigated to tackle the high-price limitations of inorganic membrane

PoSiMem: towards novel ultrathin membranes

Membrane-based filtration technologies have received intensive attention in the chemical, and petrochemical industries due to their low-energy consumption, high throughput, and low carbon footprints. Specific industrial applications such as the recovery of aromatics from hydrocarbons require robust membranes that show a good organic solvent permeability while maintaining correct retention of small organic contaminants or active molecules under harsh operating conditions (toxic organic solvents, high pressure, and temperature). Current inorganic nanofiltration (NF) membranes exhibit strong stability in many organic solvents at elevated temperatures, however due to their hydrophilic nature, amorphous structure, and high tortuosity, they present a low solvent flux.

Additionally, it is laborious to scale them up in a low defect manner to ensure the preservation of the retention performance. Novel ultrathin inorganic solvent-resistant NF membranes with well-aligned pores, a low tortuosity and an organophilic surface are expected to overcome the permeance-selectivity trade-off and enable the purification of waste streams under harsh operating conditions.

Production of novel NF membranes

PoSiMem aims to develop robust, reproducible and easy to scale-up approaches for the production of novel NF membranes composed of periodic organosilica networks and vertically aligned 2D/3D hexagonal channels. These unique inorganic NF membranes will combine the properties of the organosilica layer (hydrothermal stability, and organophilic) with the inertness and rigidity of the ceramic support, and the versatility of the periodic porous structure (meaning 2D or 3D hexagonal pores with tunable pore size).

Gaining more insight into existing synthesis routes

NF inorganic-based membranes composed of 2D or 3D hexagonal nanochannels offer a unique opportunity. Despite the recent advances in the preparation of this class of membranes for water filtration application, their preparation directly on top of porous ceramic supports with a nanometer thickness and pore diameter below 2.5 nm remains a challenge. Our main activity will be devoted to the formation of such a layer on dense and porous support using different pre-functionalization approaches. One of the aims is to gain more fundamental insight into existing synthesis routes and to develop new fabrication methods. Furthermore, low-cost methods and materials will be investigated to tackle the high-price limitations of inorganic membranes.

Result: a toolbox to separate specific molecules

As a result of this research, a platform or ‘toolbox’ of 2D/3D hexagonal organosilica nanochannels NF membranes will be available to separate specific molecules organic solvents leading to efficient refining processes and improved separation in the broad process industry.