Desalination of simulated seawater by purge-air pervaporation using an innovative fabricated membrane.
An innovative polymeric membrane has been invented, which presents a breakthrough in the field of desalination membranes. It can desalinate simulated seawater of exceptionally high concentration to produce a high flux of potable water with over 99.7% salt rejection (%SR) in a once-through purge-air pervaporation (PV) process. A set-up was constructed for conducting the desalination experiments and the effect of initial salt solution concentration (Ci) and pervaporation temperature (Tpv) on the water flux (J), %SR, separation factor, and pervaporation separation index were determined. The membrane was prepared by the phase-inversion technique, of a specially formulated casting solution consisting of five ingredients, after which the membrane was subjected to a post-treatment by which certain properties were conferred. The results confirmed that the salinity of the pervaporate was independent of Ci (all %SR above 99.7). The best result was at Tpv=70 °C, where J varied from 5.97 to 3.45 l/m2 h for Ci=40-140 g NaCl/l, respectively. The membrane morphology was confirmed to be asymmetric. The contact angle was immeasurable, indicating the membrane to be super-hydrophilic. Activation energies computed using Arrhenius law were, under all conditions investigated, less than 20 kJ/mol K.
Chemical Engineering Department Faculty of Engineering, Alexandria University, Alexandria, Egypt.
Mona
M
Naim
Research Development Department, Arab Academy for Science, Technology and Maritime Transport, Alexandria, Egypt.
Mahmoud
M
Elewa
Agricultural and Biosystems Engineering, Faculty of Agriculture, Alexandria University, Alexandria, Egypt E-mail: ahmed.elshafi@alexu.edu.eg.
Ahmed
A
El-Shafei
National Institute of Oceanography and Fisheries, Alexandria, Egypt.
Abeer
A
Moneer
D008567:Membranes, Artificial; D011108:Polymers; D054712:Salinity; D012623:Seawater; D012965:Sodium Chloride / Q000302:isolation & purification*; D012996:Solutions; D013696:Temperature; D014867:Water; D018508:Water Purification / Q000295:instrumentation*
D008567:Membranes, Artificial; D011108:Polymers; D012996:Solutions; D014867:Water; D012965:Sodium Chloride