**7. Conclusion**

The water purification by nanofiltration membrane techniques is presented, as well as the different classes of membranes. The influence of physico-chemical parameters is discussed.

The effect of pH on the adsorption capacity depends on the surface charge or zeta potential of the sorbent at different pH and presence of different electrolyte.

Purification by membrane filtration is highly dependent on the species present in water and properties of the membrane.

Membrane nanofiltration in combination with others techniques showed a high rejection.

NF membrane can be used in any types of water and it can treat organic or inorganic effluents.

For a given module, we observe that there is interest in working at a high conversion rate to limit heating of the solution (energy consumption). However, the solution to be treated is concentrated very quickly. Scaling of the cartridge will occur very quickly. We must find a compromise for the three parameters C0, Y and Qp.
