Investigating the effects of different methods of inhibitor addition on the performance of commercial reverse osmosis membranes

Abstract

Reverse osmosis membrane is the core component of reverse osmosis treatment, which is the most widely used water desalination method in industry nowadays because of its high efficiency, desirable water quality and low cost. However, inorganic salt fouling (or scaling) caused by concentration polarization on membrane surface should not be underestimated, which can seriously affect the performance of the membrane. Scale inhibitors are a group of special chemicals which are commonly added to water to retard the onset of scaling. However, there is limited research on the effect of the presence of scale inhibitors on the scaling process of reverse osmosis membranes. To fill this knowledge gap, in this report, we attach scale inhibitors to membranes by various physiochemical methods and use multiple surface characterization tools to systematically investigate the effects of different methods of inhibitor addition on the performance of reverse osmosis membranes. The experimental results show that scale inhibitors attached to membranes can effectively retard the onset of scaling. On the other hand, the scale inhibitor can have some negative effects on other performance of the reverse osmosis membrane. The results of this study can provide new insights for the research of reverse osmosis membrane scaling control.