Synthesis of Nanocomposites Forward Osmosis Membranes for Desalination of Waste and Saline water

Abstract

Nowadays, lack of clean and soft drinking water is one of the major problems faced by human society. Membrane-based separation is one of the most popular technologies for water reuse and desalination of brackish/ saltwater. Membrane-based separation became a suitable alternative to thermal separation techniques. Although the reverse osmosis (RO) process has substituted the routine thermal distillation process as the prevailing desalination technology after 40 years of development, the dramatic rise in oil prices has affected its potential for water softening. Since high hydraulic pressure must be supplied in the RO process to overcome the osmotic pressure of the feed solution, it is not reasonable to use this technique for water treatment processes. Forward osmosis (FO) is a novel membrane process that shows great potential as an alternative to the conventional membrane process. Unlike reverse osmosis (RO) that uses hydraulic pressure to create the driving force for water permeation, FO processes utilize an osmotic pressure difference between the feed and draw solution across a semipermeable membrane as the driving force to persuade the clean water to flow through the membrane to the draw solution. Compared to conventional pressure-driven membrane process such as the RO, the FO has shown many advantages namely: (1) Reduce fouling tendency and easy cleaning; (2) Low cost; (3) Higher water recovery, (4) More extensive application such as power generation, juice or food concentration, protein, and pharmaceutical enrichment, desalination and wastewater treatment. The main parts of the present study can be summarized as follows: