Hydrogen attracts growing attention for its potential as an energy source in the drive to attain carbon neutrality. It is accordingly vital to establish energy-saving and highly efficient hydrogen recovery and purification technologies to cater to swift hydrogen demand growth in coming years.
Membrane separation offers considerable potential. That is because this process can secure high-purity hydrogen by removing impurities during hydrogen production and usage, saving energy and space by employing pressure differences and enabling separation without phase changes. Polymeric separation membrane modules experience low performance degradation from water vapor and are light. There are issues, however, with hydrogen permeation purity and amounts. Toray accordingly developed a separation membrane in 2018 that precisely controls pore structures.
The company recently used a technology that it cultivated with reverse osmosis membranes to develop a separation membrane with a highly controlled pore structure by deploying a material with a high hydrogen affinity. Toray used this membrane to attain a hydrogen permeation purity of 98%, which is unmatched anywhere. This
technology can boost permeated hydrogen purity with a single separation instead of the several required with regular modules and cuts initial investment expenditure. It also reduces energy consumption and can cut the carbon dioxide emissions of conventional separation membrane modules (Figure 1) by more than 50%.
When modularizing, Toray optimally designed the channel materials of key components to reduce flow resistance. The membrane thus has double the area of conventional separation membrane modules. This improves the hydrogen permeability of a module (Figure 2) and more than halves the number of module elements needed for the hydrogen purification process. Combining the Toray-developed separation membranes can reduce the number of module elements by more than 75%, representing a tremendous space saving.
The company will partner with engineering companies in Japan and abroad while drawing on process technologies from water treatment to establish mass production techniques.
Toray will keep leveraging its core technologies of synthetic organic and polymer chemistry, biotechnology, and nanotechnology in keeping with its commitment to innovating ideas, technologies, and products that deliver new value to create advanced materials and innovative technologies that contribute to social progress.
The company plans to exhibit polymer separation membrane modules based on this technology at nano tech 2022, an international nanotechnology exhibition and conference at Tokyo Big Sight from January 26 through 28, 2022.
* Calculation assumptions
Same module dimensions
Constant hydrogen purification (feed stream composition: 80% hydrogen and 20% nitrogen + saturated water vapor)