The new module more than halves the carbon dioxide emissions of hydrogen purification processes and the number of modules required.
Hydrogen is attracting growing attention for its potential as an energy source in the drive to attain carbon neutrality. As a result, it is vital to establish energy-saving and highly efficient hydrogen recovery and purification technologies to cater to growing hydrogen demand growth in coming years.
Membrane separation offers considerable potential because it 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 vapour and are light. There are issues, however, with hydrogen permeation purity and amounts. As a result, Toray 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, the company claims, 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 by more than 50%.
When modularising, 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 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 considerable space saving.