BORSIG Membrane Technology GmbH
Our membrane technology
solvent resistant
polymeric membranes
for new applications

Liquid Separation

Organic Solvent Nanofiltration (OSN) or organophilic Nanofiltration (oNF) is a membrane-based separation technology for the gentle treatment of liquid process streams in the molecular range. 

For a long time the industrial use of nanofiltration has been limited to applications in aqueous media. The development of solvent-resistant membranes provides a new separation technology for the treatment of liquid organic process mixtures to the petrochemical, chemical, pharmaceutical and food industries.

Unlike conventional thermal separation technologies, OSN operates at mild conditions. This enables the separation of temperature-sensitive components at ambient temperatures which increases product quality and reduces energy consumption. 

Waste streams may be processed with OSN to recover valuable components, avoid product loss and reduce raw material costs.

In combination with conventional processes such as distillation, OSN is able to relieve distillation columns by treating side streams which reduces bottlenecks.

Liquid separation unit
Homogeneous catalyst recovery by Organic Solvent Nanofiltration (OSN)
Liquid separation unit

Organic Solvent Nanofiltration Unit

The principle of the OSN Unit is the cross flow over the membrane, dividing the inlet flow into solute enriched solvent upstream (concentrate) and purified solvent downstream (permeate).


Pervaporation is a membrane process which enables solvent dehydration without dependency on vapor/liquid equilibrium

The implementation of an OSN unit in a separation process may simplify the entire process by substituting one or more separation steps. The modular design additionally allows for flexible capacity adjustment.

In recent years BORSIG Membrane Technology GmbH has developed new solvent-resistant polymer membranes which are now industrially available having already proven their performance in industrial reference installations.

OSN Process Development

Due to complex interactions between the process fluids and the polymeric membranes, an intensive process development is required for OSN applications.


Organic Solvent Nanofiltration

One of our innovative membrane technologies is Organic Solvent Nanofiltration (OSN), a new separation technology for the treatment of liquid process streams in the molecular range. OSN is a pressure driven process
that operates at moderate or ambient temperatures. The separation takes place in the liquid phase. No phase transition is required for efficient separation.