Seawater Desalination Using Modified Ceramic Membranes

Nanofiltration has many applications such as pretreatment and partial demineralization in seawater desalination processes. This paper studies the performance of commercial ceramic membranes, modified by depositing either platinum or silver, to reject salts of seawater. The membrane used is multilayer structured with a titania layer (5 kD MWCO) manufactured by TAMI Industries (Nyons, France) and anionic impregnation was used to depose platinum or silver onto the membrane. The effect of salts rejection of membranes was investigated using seawater from the Mexican Pacific coast. The tests were carried out at pressure of 6 bar and the experimental results showed that modified membranes could achieve a salt rejection close to 30% in total dissolved solids (TDS) whereas the rejection in nonmodified membranes was less than 5%. Anion and cation rejection was also determined, with higher values obtained for cation removal.