1. Chemical Engineering Department; King Saud University, P.O. Box 800; Riyadh 11421 Kingdom of Saudi Arabia
2. King Abdullah Institute for Nanotechnology, King Saud University, P.O. Box- 2455; Riyadh 11451 Kingdom of Saudi Arabia
3. National Center for Water Technology, King Abdulaziz City for Science and Technology, P.O. Box 6086; Riyadh 11442 Kingdom of Saudi Arabia