Theory of Ion and Water Transport in Reverse-Osmosis Membranes

Reverse osmosis (RO) is the most energy-efficient means of harnessing the ocean as a source of water for drinking, agriculture, or industry. The basic principles have been long understood, and practiced for 50 years, but perfecting this technology takes on new importance in the face of a burgeoning world population. The authors present a comprehensive transport theory for species transiting the pores of a RO membrane, and their calculations closely match experimental data. Of particular interest is understanding and improving the rejection of boron-bearing ions, which are a health concern at typical input concentrations.