Prediction of boron transport through seawater reverse osmosis membranes using solution–diffusion model

Abstract

One of the key transport parameter—permeability, is being used as an intrinsic characteristic of membrane for reverse osmosis process prediction. In this study, the prediction of reverse osmosis process in terms of boron rejection was carried out in two steps. First, the permeability of boron existing as boric acid B(OH) 3 and as metaborate ion B(OH) 4 − through seawater reverse osmosis membranes was estimated in three types of feed matrix: DI water, NaCl and artificial seawater. The second step was to develop a computer program using boric and borate permeabilities as inputs to predict the boron rejection at different operating conditions. The governing equations were derived from the solution–diffusion model. The effect of temperature was quantitatively determined employing a representative constant and incorporated with the program. The prediction showed good agreement with experimental data obtained from a lab-scale plate-frame type reverse osmosis system.