(752g) Brackish Water Desalination with a Novel Polymer Nanocomposite Membrane

Liliana R. Villanueva López and David Suleiman, Ph.D

Chemical Engineering Department, University of Puerto Rico, Mayaguez

The rapid growth of global population, the industrialization and environmental problems caused by global warming has made it necessary to implement advanced water purification techniques capable of fulfilling the increasing demand for drinking water. According to the UNESCO, the world population surpasses 7.0 billion people and groundwater resources across the world are limited to supply the basic daily water needs for the world.

Salty water is the most abundant on earth, which represents approximately 97% of the water available. However, it is the less recovered source of water, because of the high costs required by the ion exchange technologies used. These processes are still the most commonly used for desalination processes due to their high efficiency and environmentally benign nature.

In this research, sulfonated poly(styrene-isobutylene-styrene) (SIBS) has been used to validate its efficiency as a filtration media in brackish water desalination. The effect of counter-ion substitution in the ionic domains (e.g., Ba +2, Ca +2, and Mg +2) was used as they changed the nanostructure and the resulting permeability of water and salt.

Characterization techniques employed to evaluate physicochemical properties of the polymer membranes include: infrared spectroscopy, energy dispersive X-ray spectroscopy thermogravimetric analysis, elemental analysis, water uptake, ion exchange capacity, water and salt permeability. Sulfonated membranes with counter-ions showed higher selectivities in the nanofiltration system for brackish water desalination.