LbLBRANE · Regenerable active polyelectrolyte nanofiltration membranes for water reuse and metal/acid recovery

The shortage of drinking water in many regions on the planet constitutes a real problem and hazard. The use of seawater, brackish water and wastewater for human consumption is not a new concept. In spite of the success of membrane technology in water reclamation, membrane separation systems suffer from a serious problem: membrane fouling. The main downside is an inevitabe increase in operation and maintenance costs as well as an adverse effect on the lifespan of the membrane (harsh cleaning treatment). LbLBRANE is an ambitious project ensuring competent input right from the membrane concept down to lab-scale production and optimisation before scaling-up in pilot plants for end users. LbLBRANE applies novel nanotechnology tools, namely the layer-by-layer (LbL) technology to develop a versatile and generic procedure for the fast fabrication of low-cost, stable, chemical-resistant polyelectrolyte membranes. The LbL technology is the way to go for a bottom-up nano-engineered membrane whereby the modification is performed stepwise in a controlled manner - the thickness can be finely tuned by the number of layers deposited, the architecture of the film can be compartmentalised by incorporating functional species (polyelectrolyte as well as nanoparticles with specific functions, such as antibacterial properties) and the morphology of the film can be modulated via the pH, charge density and type of polyelectrolyte pairs to create pore size (hence permeability) tailored according to the specific need of the membranes. Our concern is focused towards high performance, regenerable membranes which could be cleaned in-situ and hybrid membranes with extremely high flux with high permselectivity and mechanical robustness. The ultimate aim is towards implementation of LbL on large industrial scale, from module design and construction to end user, especially for water reuse and metal/acid recovery.