Toray Industries has developed a highly durable reverse osmosis (RO) membrane. This innovative offering guarantees the long-term provision of high-quality water. It also maintains the superior removal performance of Toray’s existing membranes vital for reusing industrial wastewater and treating sewage.

The new membrane offers double the resistance to cleaning chemicals of conventional counterparts. This reduces performance degradation from membrane wear and simplifies operational management, halving replacement frequencies and shrinking the product’s carbon footprint.

The company is preparing to mass produce this membrane and launch it in the rapidly expanding Chinese market in the first half of 2024. It looks to develop products with the new membrane for the global market including Japan.

The broad applications of RO membranes include desalinating seawater and river water, reusing wastewater, and producing drinking water as a technology to ensure sustainable water sources. Reusing wastewater entails treating water of diverse quality levels with RO membranes. The downside is that an increased reliance on cleaning chemicals to purge contaminants on the membrane surface to maintain their operational efficiency deforms their pores, diminishing removal performance. This has spurred demand for more resilient membranes.

The company combined a Toray Research Center-developed scanning transmission electron microscopy (glossary note 2) technology and a digital data analysis technique to quantitatively analyze the pore of the separation layer of RO membranes, which is smaller than one nanometer (a billionth of a meter) in diameter.

Toray drew on the analysis to identify a substructure that helps enhance pore structure stability when in contact with cleaning chemicals. It innovated a manufacturing process to design a new polymer structure, thus creating a RO membrane that delivers a stable pore structure.